JLG G5-18A Service Manual

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Service Manual

Models G5-18A

2505

31200361

Original

February 28, 2008

An Oshkosh Truck Corporation Company

EFFECTIVITY PAGE

February 28, 2008 - A - Original Issue Of Manual

31200361 G5-18A/2505 a

EFFECTIVITY PAGE

G5-18A/2505 31200361-b

SECTION CONTENTS

Section Subject Page

Section 1

Safety Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1

1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.2 Disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.3 Operation & Safety Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.4 Do Not Operate Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.5 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.6 Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.3

1.7 Safety Decals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4

Section 2

General Information and Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1

2.1 Replacement Parts and Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2

2.2 Torques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3

2.3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.4 Fluids, Lubricants and Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8

2.5 Maintenance Schedules. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

2.6 Lubrication Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.10

Section 3

Boom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1

3.1 Boom System Component Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2

3.2 Boom System - Two Section Boom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.3 Boom Assembly Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.4 Boom Wear Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10

3.5 Quick Attach Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11

3.6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.14

Section 4

Cab and Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1

4.1 Operator’s Cab and Covers Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2

4.2 Operator’s Cab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.3

4.3 Cab Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.4 Cab Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8

4.5 Cab Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9

Section 5

Axles, Drive Shafts, Wheels and Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1

5.1 Axle, Drive Shaft and Wheel Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5.2

5.2 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3 Axle Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.4 Drive Shafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.5 Wheels and Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.10

5.6 Steering Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

5.7 Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

G5-18A, 2505

Section Subject Page

Section 6

Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.1

6.1 Transmission Assembly Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2

6.2 Transmission Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.3 Transmission Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.4 Transmission Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.5 Transmission Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5

6.6 Towing a Disabled Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6

Section 7

Engine: Perkins 1104D-44T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1

7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2

7.2 Engine Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.3 Specifications and Maintenance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.4 Engine Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.5 Engine Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5

7.6 Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.5

7.7 Engine Exhaust and Air Cleaner System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7

7.8 Engine Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7

7.9 Engine Coupler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.10 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.10

Section 8

Hydraulic System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1

8.1 Hydraulic Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3

8.2 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.4 Hoses, Tube Lines, Fittings, Etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.5 Hydraulic Pressure Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5

8.6 Hydraulic Schematics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.8

8.7 Hydraulic Reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.8 Hydraulic System Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.9 Front Drive Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.13

8.10 Valves and Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.14

8.11 Hydraulic Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.23

Section 9

Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.1

9.1 Electrical Component Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2

9.2 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3

9.3 Fuses and Relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3

9.4 Electrical System Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.6

9.5 Circuit Breakdowns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.11

9.6 Engine Start Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.15

9.7 Charging Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9.16

9.8 Electrical System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.17

9.9 Window Wiper/Washer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.19

9.10 Cab Heater and Fan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.20

9.11 Switches, Solenoids and Senders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.21

G5-18A, 2505

Section 1

Safety Practices

Contents

PARAGRAPH TITLE PAGE

1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.2 Disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.3 Operation & Safety Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.4 Do Not Operate Tags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2

1.5 Safety Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.5.1 Safety Alert System and Signal Words . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.6 Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.6.1 Personal Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.6.2 Equipment Hazards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3

1.6.3 General Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4

1.6.4 Operational Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4

1.7 Safety Decals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4

G5-18A/2505

1.1

Safety Practices

1.1 INTRODUCTION

This service manual provides general directions for accomplishing service and repair procedures. Following the procedures in this manual will help assure safety and equipment reliability.

Read, understand and follow the information in this manual, and obey all locally approved safety practices, procedures, rules, codes, regulations and laws.

These instructions cannot cover all details or variations in the equipment, procedures, or processes described, nor provide directions for meeting every possible contingency during operation, maintenance, or testing. When additional information is desired consult the local JLG distributor.

Many factors contribute to unsafe conditions: carelessness, fatigue, overload, inattentiveness, unfamiliarity, even drugs and alcohol, among others. For optimal safety, encourage everyone to think, and to act, safely.

Appropriate service methods and proper repair procedures are essential for the safety of the individual doing the work, for the safety of the operator, and for the safe, reliable operation of the machine. All references to the right side, left side, front and rear are given from the operator’s seat looking in a forward direction.

Supplementary information is available from JLG in the form of Service Bulletins, Service Campaigns, Service Training Schools, the JLG website, other literature, and through updates to the manual itself.

1.2 DISCLAIMER

All information in this manual is based on the latest product information available at the time of publication. JLG reserves the right to make changes and improvements to its products, and to discontinue the manufacture of any product, at its discretion at any time without public notice or obligation.

1.3 OPERATION & SAFETY MANUAL

The mechanic must not operate the machine until the Operation & Safety Manual has been read & understood, training has been accomplished and operation of the machine has been completed under the supervision of an experienced and qualified operator.

An Operation & Safety Manual is supplied with each machine and must be kept in the cab. In the event that the Operation & Safety Manual is missing, consult the local

JLG distributor before proceeding.

1.4 DO NOT OPERATE TAGS

Place Do Not Operate Tags on the ignition key switch and the steering wheel before attempting to perform any service or maintenance. Remove key and disconnect battery leads.

1.2

G5-18A/2505

Safety Practices

1.5 SAFETY INFORMATION

To avoid possible death or injury, carefully read, understand and comply with all safety messages.

In the event of an accident, know where to obtain medical assistance and how to use a first-aid kit and fire extinguisher/fire suppression system. Keep emergency telephone numbers (fire department, ambulance, rescue squad/paramedics, police department, etc.) nearby. If working alone, check with another person routinely to help assure personal safety.

1.5.1 Safety Alert System and Signal Words

DANGER

DANGER indicates an imminently hazardous situation

which, if not avoided, will result in death or serious injury.

WARNING

WARNING indicates a potentially hazardous situation

which, if not avoided, could result in death or serious injury.

CAUTION

CAUTION indicates a potentially hazardous situation

which, if not avoided, may result in minor or moderate injury.

1.6 SAFETY INSTRUCTIONS

Following are general safety statements to consider before performing maintenance procedures on the telehandler. Additional statements related to specific tasks and procedures are located throughout this manual and are listed prior to any work instructions to provide safety information before the potential of a hazard occurs.

For all safety messages, carefully read, understand and follow the instructions before

1.6.1 Personal Hazards

PERSONAL SAFETY GEAR: Wear all the protective clothing and personal safety gear necessary to perform the job safely. This might include heavy gloves, safety glasses or goggles, filter mask or respirator, safety shoes or a hard hat.

LIFTING: NEVER lift a heavy object without the help of at least one assistant or a suitable sling and hoist.

1.6.2 Equipment Hazards

LIFTING OF EQUIPMENT: Before using any lifting equipment (chains, slings, brackets, hooks, etc.), verify that it is of the proper capacity, in good working order, and is properly attached.

NEVER stand or otherwise become positioned under a suspended load or under raised equipment. The load or equipment could fall or tip.

DO NOT use a hoist, jack or jack stands only to support equipment. Always support equipment with the proper capacity blocks or stands properly rated for the load.

HAND TOOLS: Always use the proper tool for the job; keep tools clean and in good working order, and use special service tools only as recommended.

proceeding.

G5-18A/2505

1.3

Safety Practices

1.6.3 General Hazards

SOLVENTS: Only use approved solvents that are known to be safe for use.

HOUSEKEEPING: Keep the work area and operator’s cab clean, and remove all hazards (debris, oil, tools, etc.).

FIRST AID: Immediately clean, dress and report all injuries (cuts, abrasions, burns, etc.), no matter how minor the injury may seem. Know the location of a First Aid Kit, and know how to use it.

CLEANLINESS: Wear eye protection, and clean all components with a high-pressure or steam cleaner before attempting service.

When removing hydraulic components, plug hose ends and connections to prevent excess leakage and contamination. Place a suitable catch basin beneath the machine to capture fluid run-off.

Check and obey all Federal, State and/or Local regulations regarding waste storage, disposal and recycling.

1.6.4 Operational Hazards

ENGINE: Stop the engine before performing any service unless specifically instructed otherwise.

VENTILATION: Avoid prolonged engine operation in enclosed areas without adequate ventilation.

SOFT SURFACES AND SLOPES: NEVER work on a machine that is parked on a soft surface or slope. The machine must be on a hard level surface, with the wheels blocked before performing any service.

FLUID TEMPERATURE: NEVER work on a machine when the engine, cooling or hydraulic systems are hot. Hot components and fluids can cause severe burns. Allow systems to cool before proceeding.

FLUID PRESSURE: Before loosening any hydraulic or diesel fuel component, hose or tube, turn the engine OFF. Wear heavy, protective gloves and eye protection. NEVER check for leaks using any part of your body; use a piece of cardboard or wood instead. If injured, seek medical attention immediately. Diesel fluid leaking under pressure can explode. Hydraulic fluid and diesel fuel leaking under pressure can penetrate the skin, cause infection, gangrene and other serious personal injury.

Relieve all pressure before disconnecting any component, part, line or hose. Slowly loosen parts and allow release of residual pressure before removing any part or component. Before starting the engine or applying pressure, use components, parts, hoses and pipes that are in good condition, connected properly and are tightened to the proper torque. Capture fluid in an

appropriate container and dispose of in accordance with prevailing environmental regulations.

RADIATOR CAP: Always wear steam-resistant, heat protective gloves when opening the radiator cap. Cover the cap with a clean, thick cloth and turn slowly to the first stop to relieve pressure.

FLUID FLAMABILTITY: DO NOT service the fuel or hydraulic systems near an open flame, sparks or smoking materials.

NEVER drain or store fluids in an open container. Engine fuel and hydraulic fluid are flammable and can cause a fire and/or explosion.

DO NOT mix gasoline or alcohol with diesel fuel. The mixture can cause an explosion.

PRESSURE TESTING: When conducting any test, only use test equipment that is correctly calibrated and in good condition. Use the correct equipment in the proper manner, and make changes or repairs as indicated by the test procedure to achieve the desired result.

LEAVING MACHINE: Lower the forks or attachment to the ground before leaving the machine.

TIRES: Always keep tires inflated to the proper pressure to help prevent tipover. DO NOT over-inflate tires.

NEVER use mismatched tire types, sizes or ply ratings. Always use matched sets according to machine specifications.

MAJOR COMPONENTS: Never alter, remove, or substitute any items such as counterweights, tires, batteries or other items that may reduce or affect the overall weight or stability of the machine.

BATTERY: DO NOT charge a frozen battery.Charging a frozen battery may cause it to explode. Allow the battery to thaw before jump-starting or connecting a battery charger.

1.7 SAFETY DECALS

Check that all safety decals are present and readable on the machine. Refer to the Operation & Safety Manual supplied with machine for information.

1.4

G5-18A/2505

Section 2

General Information and Specifications

Contents

PARAGRAPH TITLE PAGE

2.1 Replacement Parts and Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2

2.2 Torques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3

2.2.1 ASTM Fastener Torque Chart (English) . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3

2.2.2 ASTM Fastener Torque Chart (Metric) . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4

2.2.3 Metric Fastener Torque Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5

2.3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.1 Travel Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.2 Hydraulic Cylinder Performance Specifications. . . . . . . . . . . . . . . . . . . . . 2.6

2.3.3 Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.4 Engine Performance Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7

2.3.5 Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7

2.4 Fluids, Lubricants and Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8

2.5 Maintenance Schedules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

2.5.1 10,1st 50 & 50 Hour Maintenance Schedule. . . . . . . . . . . . . . . . . . . . . . . 2.9

2.5.2 1st 250, 250, 500 & 1000 Hour Maintenance Schedule . . . . . . . . . . . . . . 2.9

2.6 Lubrication Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.10

2.6.1 250 Hour Lubrication Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.10

G5-18A/2505

2.1

General Information and Specifications

2.1 REPLACEMENT PARTS AND WARRANTY INFORMATION

Before ordering parts or initiating service inquiries, make note of the machine serial number. The machine serial number plate is located as indicated in the figure.

MY2350

IMPORTANT: The replacement of any part on this machine with any other than a JLG authorized replacement part can adversely affect the performance, durability, or safety of the machine, and will void the warranty. JLG disclaims liability for any claims or damages, whether regarding property damage, personal injury or death arising out of the use of unauthorized replacement parts.

A warranty registration form must be filled out by the JLG distributor, signed by the purchaser and returned to JLG when the machine is sold and/or put into use.

Registration activates the warranty period and helps to assure that warranty claims are promptly processed. To guarantee full warranty service, verify that the distributor has returned the business reply card of the warranty registration form to JLG.

2.2

G5-18A/2505

2.2 TORQUES

2.2.1 ASTM Fastener Torque Chart (English)

WITH

PATCH

LOC-WEL

TORQUE

PATCH

LOC-WEL

WITHOUT

SOCKET HEAD

General Information and Specifications

UNBRAKO 1960 SERIES

SAE GRADE 8 BOLTS & GRADE 8 NUTS

& SOCKET HEAD CAP SCREWS

LOAD

CLAMP

LOCTITE

TORQUE

DRY OR

LOAD

CLAMP

LOCTITE

TORQUE

271

242 OR

262

LUB

263

LOCTITE

271

242 OR

262

LUB

VALUES FOR ZINC PLATED / YELLOW CHROMATE FASTENERS ONLY UNPLATED CAP SCREWS

G5-18A/2505

SAE GRADE 5 BOLTS &

GRADE 2 NUTS

DRY OR

CLAMP

TENSILE

BOLT

THDS.

263

LOCTITE

LOAD

AREA

STRESS

DIA.

PER

INCH

SIZE

IN SQ. IN. LB. IN-LB IN-LB IN-LB IN-LB LB. IN-LB. IN-LB IN-LB IN-LB LB. IN-LB IN-LB

0.00604 380 8 6 — — 540 12 9 — — — — —

0.1120

48 0.00661 420 9 7 — — 600 13 10 — — — — —632

0.00909 580 16 12 — — 820 23 17 — — — — —

0.1380

40 0.01015 610 18 13 — — 920 25 19 — — — — —832

0.01400 900 30 22 — — 1260 41 31 — — — — —

0.1640

36 0.01474 940 31 23 — — 1320 43 32 — — — — —1024

0.01750 1120 43 32 — — 1580 60 45 — — — — —

0.1900

32 0.02000 1285 49 36 — — 1800 68 51 — — — — —

0.0318 2020 96 75 — 105 2860 144 108 — 160 3180 160 168

0.2500

28 0.0364 2320 120 86 — 135 3280 168 120 — 185 3640 168 178

1/4

0.0524 3340 17 13 16 19 4720 25 18 22 30 5240 25 28

0.3125

24 0.0580 3700 19 14 17 21 5220 25 20 25 30 5800 27 30

5/16

0.0775 4940 30 23 28 35 7000 45 35 40 50 7750 45 50

0.3750

24 0.0878 5600 35 25 32 40 7900 50 35 45 55 8780 50 55

3/8

0.1063 6800 50 35 45 55 9550 70 55 63 80 10630 70 77

0.4375

20 0.1187 7550 55 40 50 60 10700 80 60 70 90 11870 75 82

7/16

0.1419 9050 75 55 68 85 12750 110 80 96 120 14190 110 120

0.5000

20 0.1599 10700 90 65 80 100 14400 120 90 108 130 15990 115 127

1/2

0.1820 11600 110 80 98 120 16400 150 110 139 165 18200 155 170

0.5625

18 0.2030 12950 120 90 109 135 18250 170 130 154 190 20300 165 182

9/16

0.2260 14400 150 110 135 165 20350 220 170 180 240 22600 210 231

0.6250

18 0.2560 16300 170 130 153 190 23000 240 180 204 265 25600 220 242

5/8

0.3340 21300 260 200 240 285 30100 380 280 301 420 33400 365 400

0.7500

16 0.3730 23800 300 220 268 330 33600 420 320 336 465 37300 400 440

3/4

0.4620 29400 430 320 386 475 41600 600 460 485 660 46200 585 645

0.8750

14 0.5090 32400 470 350 425 520 45800 660 500 534 725 50900 635 700

7/8

0.6060 38600 640 480 579 675 51500 900 680 687 990 60600 865 950

1.0000

12 0.6630 42200 700 530 633 735 59700 1000 740 796 1100 66300 915 1000

0.7630 42300 800 600 714 840 68700 1280 960 1030 1400 76300 1240 1365

1.1250

1-1/8

12 0.8560 47500 880 660 802 925 77000 1440 1080 1155 1575 85600 1380 1520

0.9690 53800 1120 840 1009 1175 87200 1820 1360 1453 2000 96900 1750 1925

1.2500

1-1/4

12 1.0730 59600 1240 920 1118 1300 96600 2000 1500 1610 2200 107300 1880 2070

1.1550 64100 1460 1100 1322 1525 104000 2380 1780 1907 2625 115500 2320 2550

1.3750

1-3/8

12 1.3150 73000 1680 1260 1506 1750 118100 2720 2040 2165 3000 131500 2440 2685

1.4050 78000 1940 1460 1755 2025 126500 3160 2360 2530 3475 140500 3040 3345

1.5000

1-1/2

12 1.5800 87700 2200 1640 1974 2300 142200 3560 2660 2844 3925 158000 3270 3600

ote: These torque values do not apply to cadmium plated fasteners.

2.3

General Information and Specifications

2.2.2 ASTM Fastener Torque Chart (Metric)

WITH

PATCH

LOC-WEL

TORQUE

PATCH

LOC-WEL

WITHOUT

SOCKET HEAD

UNBRAKO 1960 SERIES

LOAD

CLAMP

271

242 OR

LOCTITE

262

LOCTITE

TORQUE

LUB

263

DRY OR

LOCTITE

& SOCKET HEAD CAP SCREWS

SAE GRADE 8 BOLTS & GRADE 8 NUTS

VALUES FOR ZINC PLATED / YELLOW CHROMATE FASTENERS ONLY UNPLATED CAP SCREWS

LOAD

CLAMP

271

242 OR

LOCTITE

262

LOCTITE

TORQUE

LUB

GRADE 2 NUTS

SAE GRADE 5 BOLTS &

DRY OR

263

LOCTITE

2.4

LOAD

CLAMP

AREA

STRESS

TENSILE

IN SQ. IN. LB. N, m N, m N, m N, m LB. N, m N, m N, m N, m LB. N, m N, m

DIA.

BOLT

PER

INCH

THDS.

SIZE

IN SQ. IN. LB. N, m N, m N, m N, m LB. N, m N, m N, m N, m LB. N, m N, m

Note: These torque values do not apply to cadmium plated fasteners.

G5-18A/2505

General Information and Specifications

2.2.3 Metric Fastener Torque Chart

VALUES FOR ZINC PLATED / YELLOW CHROMATE FASTENERS ONLY

CLASS 8.8 METRIC BOLTS &

CLASS 8 METRIC NUTS

TORQUE

LUB

LOCTITE

262

LOCTITE

242 OR

271

CLAMP

SIZE PITCH

TENSILE

STRESS

AREA

CLAMP

LOAD

DRY OR LOCTITE

263

sq. mm KN N, m N, m N, m N, m KN N, m N, m N, m N, m

3 .5 5.03 2.19 1.3 1.0 1.2 1.4 3.13 1.9 1.4 1.5 2.1

3.5 .6 6.78 2.95 2.1 1.6 1.9 2.3 4.22 3.0 2.2 2.4 3 .3

4 .7 8.78 3.82 3.1 2.3 2.8 3.4 5.47 4.4 3.3 3.5 4.8

5 .8 14.2 6.18 6.2 4.6 5.6 6.8 8.85 8.9 6.6 7.1 9.7

6 1 20.1 8.74 11 7.9 9.4 12 12.5 15 11 12 17

7 1 28.9 12.6 18 13 16 19 18 25 19 20 28

81.2536.615.92519232822.837272940

10 1.5 58.0 25.2 50 38 45 55 36.1 72 54 58 79

12 1.75 84.3 36.7 88 66 79 97 52.5 126 95 101 139

14 2 115 50.0 140 105 126 154 71.6 200 150 160 220

16 2 157 68.3 219 164 197 241 97.8 313 235 250 344

18 2.5 192 83.5 301 226 271 331 119.5 430 323 344 473

20 2.5 245 106.5 426 320 383 469 152.5 610 458 488 671

22 2.5 303 132.0 581 436 523 639 189.0 832 624 665 915

24 3 353 153.5 737 553 663 811 220.0 1060 792 845 1170

27 3 459 199.5 1080 810 970 1130 286.0 1540 1160 1240 1690

30 3.5 561 244.0 1460 1100 1320 1530 349.5 2100 1570 1680 2310

33 3.5 694 302.0 1990 1490 1790 2090 432.5 2600 2140 2280 2860

36 4 817 355.0 2560 1920 2300 2690 509.0 3660 2750 2930 4020

42 4.5 1120 487.0 4090 3070 3680 4290 698.0 5860 4400 4690 6440

CLASS 10.9 METRIC BOLTS &

CLASS 10 METRIC NUTS

LOAD

DRY OR

LOCTITE

263

LUB

TORQUE

LOCTITE

262

LOCTITE

242 OR

271

Note: These torque values do not apply to cadmium plated fasteners.

G5-18A/2505

METRIC CLASS 8.8METRIC CLASS 10.

2.5

General Information and Specifications

2.3 SPECIFICATIONS

2.3.1 Travel Speed

12 x 16.5 Tires (Standard) 16 mph (26 kmph)

14 x 17.5 Tires 18 mph (29 kmph)

2.3.2 Hydraulic Cylinder Performance Specifications

Note: Machine with no load, engine at full throttle, hydraulic oil above 130° F (54° C) minimum, engine at operating temperature.

Function Approximate Times (sec.)

Boom Extend 6

Boom Retract 4

Boom Lift 6

Boom Lower 4

Attachment Tilt - UP 2

Attachment Tilt - DOWN 2

2.3.3 Electrical System

Note: Refer to Section 9.3, “Fuses and Relays,” for more information.

Battery:

Type, Rating 12V DC, Negative (-) Ground, Limited Maintenance,

Wet Charged

Quantity 1 (100 Ah) (C

Reserve Capacity CCA @ -.4° F: 880 EN

Group/Series DIN 600,44

Alternator 12V, 75 Amps

Starter 12V, 3,0 KW Type EV (Gear Reduction)

)

2.6

G5-18A/2505

General Information and Specifications

2.3.4 Engine Performance Specifications

Description

Engine Make/Model Perkins 1104D-44T

Low Idle 900 ±50 rpm

High Idle 2150 ±50 rpm

Horsepower 84 BHP/ 64,5 kW @ 2200 rpm

Fuel Delivery Fuel Injection

Air Cleaner Dry Type, Replaceable Primary and Safety Elements

Average Fuel Consumption (dependant on load/duty) 1.6 gal/hr (6,1 I/hr)

2.3.5 Tires

Size Tire Type Minimum Ply/

Star Rating

12 x 16.5 NHS 12 Ply Pneumatic 80 psi (5,5 bar)

14 x 17.5 NHS 12 Ply Pneumatic 70 psi (4,8 bar)

Note: Standard wheel lug nut torque is 210-230 lb-ft (285 - 312 Nm).

Fill Type Pressure

Approx. 220 lb foam

G5-18A/2505

2.7

General Information and Specifications

2.4 FLUIDS, LUBRICANTS AND CAPACITIES

Engine Crankcase Oil

Capacity w/Filter Change 9.6 quarts (9,0 liters)

Filter Capacity 1.05 quarts (1,0 liter)

Oil Type 15W-40 CE

Fuel Tank

Capacity 24 gallons (90,8 liters)

Type of Fuel U.S.A. #2 Diesel

Cooling System

System Capacity w/o Heater 14.6 quarts (13,8 liters)

Type of Fluid 50/50 mix of ethylene glycol & water

Axles

Differential Housing Capacity - Front 3.6 quarts (3,4 liters)

Axle Drop Box - Front 21 ounces (0,6 liters)

Differential Housing Capacity - Rear 3.6 quarts (3,4 liters)

Wheel End Capacity 10 ounces (0,3 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Brakes

Master Cylinder Capacity 0.7 quarts (0,7 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Hydraulic System

System Capacity 23.5 gallons (89 liters)

Reservoir Capacity to FULL Mark 16 gallons (60,6 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Auxiliary Hydraulic Circuit Max Flow 20 GPM (75,7 LPM)

2.8

G5-18A/2505

General Information and Specifications

2.5 MAINTENANCE SCHEDULES

2.5.1 10,1st 50 & 50 Hour Maintenance Schedule

EVERY

Check Fuel

Level

Check Wheel

Lug Nut

Torque

LB/FT (Nm)

EVERY

Check Tire

Pressure

Check Engine

Oil Level

Check Hydraulic

Oil Level

2.5.2 1st 250, 250, 500 & 1000 Hour Maintenance Schedule

250

Change Axle Oil

Change Wheel

End Oil

EVERY

250

Check Boom

Bearing

Pads

Lubrication

Schedule

Check Axle

Oil Level

EVERY

Check Wheel

End Oil Levels

500

( N

)

Change Fuel

Filter

Check Wheel

Lug Nut

Torque

Change Engine

Oil and

Filter

Change

Air Filter

Check Engine Coolant Level

Drain Fuel/

Water

Separator

Check

Air Filter

MY2560

Change Axle Oil

Change

Engine Coolant

Change Wheel

End Oil

EVERY

1000

Change

Hydraulic

Fluid & Filters

Check

Hydraulic Tank

Cap

Change

Transmission

Filter

MY2570

G5-18A/2505

2.9

General Information and Specifications

2.6 LUBRICATION SCHEDULE

2.6.1 250 Hour Lubrication Schedule

EVERY

250

MYSTIK TETRIMOLY

(NLGI 2 GC-LB)

2.10

MY2580

G5-18A/2505

Section 3

Boom

Contents

PARAGRAPH TITLE PAGE

3.1 Boom System Component Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2

3.2 Boom System - Two Section Boom. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.2.1 Boom System Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.3 Boom Assembly Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.3.1 Second Section Boom Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.3.2 First Boom Section Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4

3.3.3 First Boom Section Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

3.3.4 Second Boom Section Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

3.3.5 Complete Boom Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

3.3.6 Second Section Boom Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6

3.3.7 Second Section Boom Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.7

3.3.8 Boom Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.7

3.3.9 Extend/Retract Cylinder Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.8

3.3.10 Extend/Retract Cylinder Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

3.4 Boom Wear Pads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10

3.4.1 Wear Pad Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10

3.4.2 Boom Wear Pad Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10

3.4.3 Boom Wear Pad Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11

3.5 Quick Attach Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11

3.5.1 Connecting with a Mechanical JLG Quick Attach . . . . . . . . . . . . . . . . . . . 3.11

3.5.2 Connecting with a Hydraulic JLG Quick Attach. . . . . . . . . . . . . . . . . . . . . 3.11

3.5.3 Connecting with a Universal Quick Attach . . . . . . . . . . . . . . . . . . . . . . . . 3.12

3.5.4 Connecting a Hydraulic Operated Attachment . . . . . . . . . . . . . . . . . . . . . 3.12

3.5.5 Quick Attach Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13

3.5.6 Quick Attach Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13

3.6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

G5-18A/2505

3.1

Boom

3.1 BOOM SYSTEM COMPONENT TERMINOLOGY

To understand the safety, operation and maintenance information presented in this section, it is necessary that the operator/mechanic be familiar with the names and locations of the major assemblies of the boom system. The following illustration identifies the components that are referred to throughout this section.

FIRST BOOM

SECTION

COMPENSATING

CYLINDER

TILT

CYLINDER

SECOND

BOOM

SECTION

EXTEND/RETRACT

AUXILIARY HYDRAULIC

QUICK CONNECTS

QUICK

ATTA CH

PIVOT PIN

CYLINDER

MY1940

3.2

G5-18A/2505

Boom

3.2 BOOM SYSTEM - TWO SECTION BOOM

3.2.1 Boom System Description

The boom operates via an interchange among the electrical, hydraulic and mechanical systems. Components involved include the joystick, tilt cylinder, extend/retract cylinder, lift/lower cylinder, compensating cylinder, electronic sensors, various pivots, supporting hardware and other components.

3.3 BOOM ASSEMBLY MAINTENANCE

The boom assembly consists of the first and second section booms and supporting hardware.

Note: Before removing the boom or boom section, the carriage or any other attachment must be removed from the quick attach.

Before beginning, conduct a visual inspection of the machine and work area, and review the task about to be undertaken. Read, understand and follow these instructions.

During service of the boom, perform the following:

1. Check wear pads. (Refer to Section 3.4.1, “Wear Pad Inspection.”)

2. Apply grease at all lubrication points (grease fittings). (Refer to Section 2.6, “Lubrication Schedule.”)

3. Check for proper operation by operating all boom functions through their full ranges of motion several times.

Depending on your particular circumstance, the following procedures explain the removal/installation of individual boom sections or removal/installation of the complete boom.

3.3.1 Second Section Boom Removal

1. Remove any attachment from the quick switch assembly.

2. Be sure there is enough room in front of the machine to allow the boom sections to be removed. Park the machine on a hard, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

3. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

4. Remove the battery negative (-) cable from the battery negative (-) terminal.

5. Open the engine cover. Allow the system fluids to cool.

6. Remove the quick switch assembly. Refer to Section

3.5.5, “Quick Attach Removal.”

7. Label and disconnect the tilt hoses and (if equipped) auxiliary hydraulic hoses attached to the machine at the boom head. Plug and cap the hose ends to prevent dirt and debris from entering the hydraulic system.

8. Label and disconnect the extend/retract hydraulic tubes on the extend/retract cylinder at the rear of the boom.

9. Tag or identify each hose to the corresponding fitting it was removed from.

10. Remove the top and side wear pads from the rear of the second boom section.

Note: Tag each pad, backing plate, shim and bolts from each location.

MY1960

11. Remove the lock bolt and nut (1) from the rear of the extend/retract cylinder.

12. Remove the extend/retract cylinder mounting pin (2).

13. Support the front of the boom by placing a sling behind the boom head. Pull the second boom section out of the first boom section approximately 6 in to 8 in (15 cm to 20 cm).

14. Pull the tilt hoses and (if equipped) auxiliary hydraulic hoses through the rear of the boom.

15. Remove the top, side and bottom wear pads from the front of the first boom section.

Note: Tag each pad, backing plate, shim and bolts from each location.

G5-18A/2505

3.3

Boom

16. Pull the second boom section halfway out of the first boom section, reposition the sling, balancing the second boom section and remove from the first boom section.

17. Set the second boom section on level ground. Set the complete boom on suitable stands to begin tear down.

18. Inspect the boom and welds. Consult your local JLG distributor if structural damage is detected.

19. Inspect hoses, hardware, wear pads, mounting points and other components visible with the first boom section. Replace any item if damaged.

20. Inspect all wear pads for wear. (Refer to Section

3.4.1, “Wear Pad Inspection.”)

3.3.2 First Boom Section Removal

1. Temporarily install the battery negative (-) cable to the battery negative (-) terminal.

2. Start the machine and raise the first boom section to gain access to the lift cylinder pin and the comp cylinder pin.

Note: DO NOT activate ANY boom function other than the boom lift function. Activating the extend/retract, tilt or auxiliary function could cause hydraulic oil to spray onto the machine and/or surrounding areas.

3. Remove the battery negative (-) cable from the battery negative (-) terminal.

4. Support the first boom section by placing a sling at the balance point of the section.

MY1980

6. Remove the lock bolt and pin (3) from the rod end of the compensating cylinder on the first boom section. Rest the cylinder on the machine frame.

7. Remove the lock bolt and pivot pin (4) from rear of first boom section.

8. Lift the first boom section off machine and set on level ground or supports being careful not to damage the tubes on the bottom of the boom.

9. Inspect the boom and welds. Consult your local JLG distributor if structural damage is detected.

10. Inspect hoses, hardware, wear pads, mounting points and other components visible with the first boom section. Replace any item if damaged.

11. Inspect all wear pads for wear. (Refer to Section

3.4.1, “Wear Pad Inspection.”)

MY1970

5. Support the lift/lower cylinder and remove the lock bolt (1) and then the rod end pin (2). Lower the lift/ lower cylinder onto the frame rails.

3.4

G5-18A/2505

Boom

3.3.3 First Boom Section Installation

Note: Light lubrication of the boom wear surfaces with a factory authorized grease is recommended to keep the boom wear surfaces lubricated properly. Light lubrication of the boom wear surfaces is also recommended when the machine is stored, to help prevent rusting.

1. Park the machine on a hard, level surface, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

Note: Grease the boom pivot bore, compensating cylinder rod ends, lift/lower cylinder rod end and pins before installing.

4. Using suitable slings, balance the first boom section, lift and carefully guide the boom into place. Align the frame pivot bore with the boom assembly pivot bore. Install boom pivot pin (5) and lock bolt. Apply

Loctite

5. With the sling still in place, install the compensating cylinder, pin (6) and lock bolt. Apply Loctite and torque to 66 lb-ft (90 Nm).

6. With the sling still in place, install the rod end of the lift/lower cylinder, pin and lock bolt. Apply Loctite #242 and torque to 66 lb-ft (90 Nm).

Note: Raising the boom up or down with the sling may be necessary so the boom, compensating and lift/lower cylinder bores can be aligned for easier pin installation.

7. Make sure boom section is level, then remove sling.

#242 and torque to 66 lb-ft (90 Nm).

MY1980

#242

3.3.4 Second Boom Section Installation

1. If previously removed, install the extend/retract cylinder into the rear of the second boom section. Pin and clip the barrel end of the cylinder in place.

2. Using suitable slings, balance the second boom section, lift and carefully guide the boom into place.

3. Install the wear pads, shims and bolts to their proper location at the front inside of the first boom section. DO NOT tighten the wear pads at this time.

4. Feed the tilt cylinder hoses and if equipped, the auxiliary hoses through the channel above the extend/retract cylinder.

5. Install the wear pads, shims and bolts previously removed from the rear of the second boom section. DO NOT tighten the wear pads at this time.

6. Uncap and reconnect the extend/retract cylinder fittings and plugs from extend/retract cylinder tubes. Attach each tube to the extend/retract cylinder fittings and tighten until wrench-tight. Mark the fitting, then tighten each tube firmly 1 to 1,5 flats.

7. Uncap and reconnect the tilt hoses and (if equipped) auxiliary hoses. Attach both sets to their appropriate fittings until wrench-tight. Mark the fitting, then tighten each hose firmly 1 to 1,5 flats.

8. Adjust and shim each wear pad as needed.

9. Start the engine and operate all boom functions several times to bleed any air out of the hydraulic system. Check for fluid leaks. Check the hydraulic fluid level in the tank and add fluid as required.

10. Clean up all debris, hydraulic fluid, etc., in, on, near and around the machine.

11. Close and secure the engine cover.

3.3.5 Complete Boom Removal

1. Remove any attachment from the quick switch assembly.

2. Be sure there is enough room in front of the machine to allow the boom sections to be removed. Park the machine on a hard, level surface, fully retract the boom, Raise the boom to allow access to the lift cylinder and the comp cylinder pivot pins, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

G5-18A/2505

3.5

Boom

3. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

4. Remove the battery negative (-) cable from the battery negative (-) terminal.

5. Open the engine cover. Allow the system fluids to cool.

6. Remove the quick switch assembly. Refer to Section

3.5.5, “Quick Attach Removal.”

7. Support the boom by placing a sling around the boom head. Support the lift/lower cylinder and remove the lock bolt and then the rod end pin. Lower the lift/lower cylinder onto the frame rails.

8. Label and disconnect the tilt and auxiliary hydraulic hoses attached to the machine at the tubes on top of the boom. Plug and cap the hose ends to prevent dirt and debris from entering the hydraulic system.

9. Label and disconnect the extend/retract hydraulic hoses at the tubes on the side of the boom.

Note: Tag or identify each hose to the corresponding fitting it was removed from.

10. Remove the lock bolt and pin (1) from the rod end of the compensating cylinder on the first boom section. Rest the cylinder on the machine frame.

3.3.6 Second Section Boom Removal

1. At the boom head, attach a sling around the tilt cylinder. Remove both hoses from tilt cylinder. Plug the hose ends and cap the tilt cylinder fittings to prevent dirt and debris from entering the hydraulic system. Remove the clip from barrel end of tilt cylinder pin. Remove the tilt cylinder pin and lower the tilt cylinder out of the boomhead.

2. Remove the extend /retract tubes from the extend / retract cylinder from the rear of the boom.

3. If equipped, unscrew the auxiliary hoses. Plug the hose ends to prevent dirt and debris from entering the hydraulic system.

Note: Tag or identify each hose to the corresponding fitting it was removed from.

MY1990

MY1980

11. Lower the boom to a level position and place a suitable support under the rear of the boom. Reposition the slings to each end of the boom.

12. Remove the lock bolt and pivot pin (2) from rear of first boom section.

13. Lift the complete boom off machine and set on level ground or supports being careful not to damage the tubes on the bottom of the boom.

4. Remove the lock nut, bolt and pin from rod end of the extend/retract cylinder.

5. Pull the second boom section out 6 in to 8 in (15 cm to 20 cm) to be able to loosen and remove all the bolts and remove all the wear pads, backing plates and shims from the rear outside of the second section boom and the front inside of the first section boom. Tag each pad, backing plate, shim and bolts from each location.

6. Carefully pull the tilt and auxiliary hydraulic hoses (3) through the rear of the first boom section.

WARNING

NEVER weld or drill the boom unless approved in

writing by JLG. The structural integrity of the boom will be impaired if subjected to any repair involving welding or drilling. Failure to comply could result in death or severe personal injury.

7. Pull out the remainder of the second boom section.

3.6

G5-18A/2505

Boom

8. Inspect the boom and welds. Consult your local JLG distributor if structural damage is detected.

9. Inspect hoses, hardware, wear pads, mounting points and other components visible with the first boom section. Replace any item if damaged.

10. Inspect all wear pads for wear. (Refer to Section

3.4.1, “Wear Pad Inspection.”)

3.3.7 Second Section Boom Installation

1. If previously removed, insert the extend/retract cylinder through the rear of the second boom section and attach the pin and clip to the barrel end.

2. Install the bottom rear wear pads, washers and bolts into the second boom section. Apply Loctite and torque to 66 lb-ft (90 Nm).

Note: Apply Loctite

#242 to all wear pad bolts prior to

installing wear pads.

3. Grease the inside of the first boom section on areas where the second boom section wear pads will slide.

4. Using a suitable sling, carefully slide the second boom section 3 ft to 4 ft (1 m to 1.5 m) into the front of the first boom section. Set the second boom section head onto suitable supports and reset sling under the boom head of the second section. Carefully slide the second section into the first section. Leave 6 in to 8 in (15 cm to 20 cm) of the second section out to be able to install wear pads in front of the first boom section.

5. With the sling still under the boom head, install the top wear pads, washers and bolts in the front of the first boom section. Apply Loctite

#242 and torque to 66 lb-ft (90 Nm). Raise the second boom section and install the bottom wear pads, backing plates, shims and bolts in the front of the first boom section Apply Loctite

#242 and torque to 66 lb-ft (90 Nm). Install the left and right side front wear pads, backing plates, shims and bolts in the front of the first boom

section. Apply Loctite

#242 and torque to 66 lb-ft

(90 Nm).

6. Install the top rear left and right side wear pads, backing plate and bolts (do not shim or tighten bolts). Install the left and right side rear wear pads, backing plates and bolts, do not shim or tighten bolts).

#242

8. Slide the tilt and auxiliary hoses between the boom sections.

9. Insert the pin and secure the rod end of the extend/ retract cylinder in place with the bolt and locknut.

10. Install both tubes to the rear of the extend/retract cylinder.

11. Lift the tilt cylinder into place and insert the pins and clips to secure the cylinder to the boomhead.

12. Uncap and reconnect the tilt and auxiliary hoses and attach to their appropriate locations.

3.3.8 Boom Installation

1. Park the machine on a hard, level surface, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

Note: Grease the boom pivot bore, compensating cylinder rod ends, lift/lower cylinder rod end and pins before installing.

4. Using suitable slings, balance the boom assembly, lift and carefully guide the boom into place. Align the frame pivot bore with the boom assembly pivot bore. Install boom pivot pin (4) and lock bolt. Apply

Loctite

5. With the sling still in place, install the compensating cylinder, pin (5) and lock bolt. Apply Loctite and torque to 66 lb-ft (90 Nm).

#242 and torque to 66 lb-ft (90 Nm).

#242

Note: Light lubrication of the boom wear surfaces with a factory authorized grease is recommended to keep the boom wear surfaces lubricated properly.

7. Tighten all rear wear pad bolts after ensuring the minimum gap requirements have been met. Refer to Section 3.4.1, “Wear Pad Inspection.”

G5-18A/2505

MY1980

3.7

Boom

6. With the sling still in place, install the rod end of the

lift/lower cylinder, pin and lock bolt. Apply Loctite #242 and torque to 66 lb-ft (90 Nm).

Note: Raising the boom up or down with the sling may be necessary so the boom, compensating and lift/lower cylinder bores can be aligned for easier pin installation.

7. Uncap and reconnect the extend/retract cylinder fittings and plugs from extend/retract cylinder tubes. Attach each tube to the extend/retract cylinder fittings and tighten until wrench-tight. Mark the fitting, then tighten each tube firmly 1 to 1,5 flats.

8. Uncap and reconnect the tilt hoses and (if equipped) auxiliary hoses. Attach both sets to their appropriate fittings until wrench-tight. Mark the fitting, then tighten each hose firmly 1 to 1,5 flats.

10. Check clearance (1) between the tilt hoses (and if equipped) auxiliary hoses and the front of the extend/retract cylinder trunnion. There should be approximately 1/2 in. (12,7 mm) of clearance.

11. If adjustment is needed, loosen the tilt tubes (and if equipped) auxiliary tubes. Move tubes to achieve the proper clearance.

3.3.9 Extend/Retract Cylinder Removal

1. Remove any attachment from the quick attach assembly. Refer to Section 3.5, “Quick Attach Assembly.”

2. Park the machine on a hard, level surface, extend the boom to gain access to the extend/retract cylinder pin in the second boom section (approximately 3 ft (1 m), level the boom assembly, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

Note: The boom must be properly aligned (level) with the access hole at the rear of the frame to allow removal of the extend/retract cylinder barrel mounting pin.

3. Place a Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

4. Open the engine cover. Allow the system fluids to cool.

MY2000

12. Clean up all debris, hydraulic fluid, etc., in, on, near and around the machine.

13. Close and secure the engine cover.

MY2680

5. Remove the battery negative (-) cable from the battery negative (-) terminal.

6. Remove the cylinder rod eye retaining clips and mounting pin (2) at the side of the second boom section.

7. Loosen and remove the hose clamps and cover plate (3) from the rear of the boom assembly.

8. Label and disconnect the tilt and auxiliary hydraulic hoses attached to the machine at the tubes on top of the boom (4). Plug and cap the hose ends to prevent dirt and debris from entering the hydraulic system.

9. Loosen and remove the extend/retract cylinder tubes at the rear of the first boom section. Plug the tube ends to prevent dirt and debris from entering the hydraulic system.

3.8

G5-18A/2505

Boom

10. Loosen and remove both fittings from the bottom of the extend/retract cylinder barrel. Plug the openings in the extend/retract cylinder barrel.

11. Loosen and remove the locking bolt on the cylinder barrel mounting pin.

12. Remove the cylinder barrel pin (5). Note the location of the spacers and washers.

13. Attach a sling or other suitable lifting device to the extend/retract cylinder and carefully pull the extend/ retract cylinder free of the machine through the rear of the boom/chassis assembly.

Note: The tilt hoses and if equipped, the auxiliary hoses may need to be moved during removal of the extend/ retract cylinder.

14. Place the extend/retract cylinder in a designated area for the next operation.

3.3.10 Extend/Retract Cylinder Installation

1. Carefully install the extend/retract cylinder into the rear of the boom and line up the barrel end of the cylinder with the pin bores on the first boom section.

Note: The tilt hoses and if equipped, the auxiliary hoses may need to be moved during installation of the extend/ retract cylinder.

5. Uncap and reconnect the tilt hoses and (if equipped) auxiliary hoses (4). Attach both sets to their appropriate fittings until wrench-tight. Mark the fitting, then tighten each hose firmly 1 to 1,5 flats.

6. Install the cover plate and hose clamps (3) at the rear of the boom assembly.

7. Install the battery negative (-) cable to the battery negative (-) terminal.

8. Start the machine and extend the extend/retract cylinder until the rod eye of the cylinder aligns with the pin bore in the second boom section.

9. Shut the engine OFF.

10. Install the mounting pin through the side of the second boom section (2) and secure with the retaining clips.

11. Start the machine and cycle the extend/retract cylinder checking for leaks or any alignment problems.

2. Install the mounting pin (5), spacers and washers through the frame access hole on the chassis and the first boom section bore and cylinder barrel. Secure with retaining clips.

MY2670

3. Remove the plugs in the bottom of the extend/retract cylinder and install the previously removed fittings.

4. Uncap and connect the tubes to the previously labeled fittings at the extend/retract cylinder. Apply Loctite 545

to the fittings.

G5-18A/2505

3.9

Boom

3.4 BOOM WEAR PADS

On the G5-18A a total of 14 wear pads are installed on the boom.

Twelve of the fourteen wear pads on this boom are flat rectangular wear pads with metal inserts. Two wear pads on the bottom of the second section boom are channeled for tilt hose and auxiliary hose clearance.

3.4.1 Wear Pad Inspection

Inspect all wear pads (2) for wear. If the angle indicators (3) on the ends of the wear pads are visible, the wear pads can be reused. If the pads show uneven wear (front to back), they should be replaced. Replace pads as a set if worn or damaged.

MY2010

MA2070

3.4.2 Boom Wear Pad Replacement

When replacing a wear pad on the boom, replace both wear pads on that side of the boom; e.g.: replace top front left and top front right wear pads at the same time.

Usually, shimming will remain the same when installing new wear pads. All wear pads are secured to the boom using different capscrews and washers. When installing new wear pads, apply Loctite mounting capscrews M10 x 1,5 and torque to 23 lb-ft (31Nm). On 5/16 x 18 capscrews, apply Loctite and torque to 17 lb-ft (23 Nm). Grease the new pads and surrounding area.

The boom wear pads are mounted on the inside of the first boom section (4) and the outside of the second boom section (5).

#242 to all wear pad

#242 to

MY2020

Use shims under the wear pads as required to maintain a maximum gap of 0.06 in (1,5 mm) (6) between the wear pad on the front and sides of the boom. The gap at the rear of the boom should be no more than 0.12 in (3 mm).

Shims are available in four thicknesses, 0.02 in (0,5mm),

0.04 in (1 mm), 0.06 in (1,5mm) and 0.08 in (2,0mm).

3.10

MU4080

G5-18A/2505

Boom

3.4.3 Boom Wear Pad Lubrication

After replacing any wear pad(s), or after prolonged periods of inoperation, light lubrication of the boom wear surfaces with a factory authorized grease is recommended to keep the boom wear surfaces lubricated properly. Light lubrication of the boom wear surfaces is also recommended when the machine is stored, to help prevent rusting.

Note: The first shim next to the pad needs to be the one with holes, instead of the slots.

3.5 QUICK ATTACH ASSEMBLY

This machine is equipped with a JLG Quick Attach system for easy attachment changes. An optional Universal Quick Attach system is also availiable.

MY2620

3.5.1 Connecting with a Mechanical JLG Quick Attach

1. Retract quick attach device to provide clearance. Check to be sure the retainer pin (1) is out.

2. Align attachment pin (2) with recess in attachment (3). Raise boom slightly to engage attachment pin in recess.

3. Engage quick attach device.

4. Shut off engine. Exit cab and insert lock pin and secure with retainer pin.

5. If attachment is equipped, connect auxiliary hydraulic hoses to the corresponding auxiliary hydraulic fittings on the side of the boom head. See Section 3.5.4, “Connecting a Hydraulic Operated Attachment.”

G5-18A/2505

3.5.2 Connecting with a Hydraulic JLG Quick Attach

1. Retract quick attach device to provide clearance. Check to be sure lock pin (4) is disengaged.

MY2620

3.11

Boom

2. Align attachment pin (2) with recess in attachment (3). Raise boom slightly to engage attachment pin in recess.

3. Engage quick attach device.

4. Press and hold button (5) and button (6), at the same time move the joystick right to engage or left to disengage the quick attach device.

MY2610

5. Raise the boom to eye level and visually check that the quick attach pin protrudes through the hole. If the pin does not protrude through the hole, place the attachment on the ground and return to step 2.

MY2600

3.5.3 Connecting with a Universal Quick Attach

This installation procedure is designed for one-person operation.

1. Retract quick attach device to provide clearance. Check to be sure the lock pin handles (7) and pins (8) are pulled up.

2. Align engaging edge (9) with recess in attachment (10). Raise boom slightly to engage attachment pin in recess.

3. Engage quick switch device.

4. Shut off engine. Exit cab and lower lock pin handles and engage lock pins.

ENGAGED

DISENGAGED

6. If attachment is equipped, connect auxiliary hydraulic hoses to the corresponding auxiliary hydraulic fittings on the side of the boom head. See Section 3.5.4, “Connecting a Hydraulic Operated Attachment.”

3.12

MY2630

3.5.4 Connecting a Hydraulic Operated Attachment

1. Install the hydraulic Attachment. See Section 3.5.2, “Connecting with a Hydraulic JLG Quick Attach,” Section 3.5.3, “Connecting with a Universal Quick Attach,” or Section 3.5.4, “Connecting a Hydraulic Operated Attachment,”

2. Lower the attachment to the ground and set the park brake.

3. Press and hold button (11), at the same time move the joystick to the right to relieve pressure at the female auxiliary fitting (12).

4. Connect the attachment hose to the female auxiliary fitting.

5. Press and hold button (11), at the same time move the joystick to the left to relieve pressure at the male auxiliary fitting (12).

6. Connect the attachment hose to the male auxiliary fitting.

G5-18A/2505

MY2640

MY2650

3.5.5 Quick Attach Removal

1. If equipped with a hydraulic quick attach device, remove both hydraulic hoses (13) from the valve body on the left side of the boom head.

2. Remove the lock bolt (14) holding the tilt cylinder rod end pin (15) to the quick attach assembly. Remove the tilt cylinder pin.

3. Support the quick attach assembly. Remove the lock bolt (16) holding the quick assembly pin (17) to the quick attach assembly. Remove the pin from the quick attach assembly from either side.

4. Inspect the above pin for nicks or surface corrosion. Use fine emery cloth to fix minor nicks or corrosion. If damaged or if it cannot be repaired the pin must be replaced.

Boom

3.5.6 Quick Attach Installation

1. Assemble the quick attach to the boom head. Line up the quick attach between the mounts on the boom head. The quick attach should be centered in the boom head.

2. Coat the quick attach pivot pin (17) with an anti-seize compound. Insert the quick attach pivot pin through the quick attach and boom head.Align the pivot pin and quick attach. Install the lock bolt (16). Torque to 72 lb-ft (97 Nm).

3. Align the quick attach with the tilt cylinder rod end and insert the tilt cylinder pin (15). Align the tilt cylinder pin and quick attach. Install the lock bolt (14). Torque to 72 lb-ft (97 Nm).

1. If equipped, reconnect the hydraulic attach switch device hoses (13) to the auxiliary valve on the left side of the boom head.

G5-18A/2505

MY2660

3.13

Boom

3.6 TROUBLESHOOTING

This section provides an easy reference guide covering the most common problems that occur during operation of the boom.

Boom Troubleshooting

Problem Cause Remedy

1. Boom will not extend or retract.

2. Boom will not fully extend. 1. Extend/retract hydraulic system

3. Boom shifts to right or left when extending.

4. Excessive pivot pin noise and/or wear.

1. Broken hydraulic hose(s) or tube(s) and/or connections leaking.

2. Extend/Retract hydraulic system not operating properly.

3. Faulty extend/retract cylinder. 3. Repair cylinder (Refer to Section

not operating properly.

1. Boom side wear pads improperly shimmed or worn.

1. Insufficient lubrication. 1. Lubricate at regular intervals.

2. Worn bushing(s). 2. Replace bushing(s) and

1. Locate break, replace hose(s) or tube(s), tighten connections.

2. Refer to Section 8, “Hydraulic System.”

8.11.4, “Cylinder Inspection.”)

1. Refer to Section 8, “Hydraulic System.”

1. Shim wear pads to correct gap. Replace wear pads as needed. Refer to Section 3.4.2, “Boom Wear Pad Replacement.”

(Refer to Section 2.6, “Lubrication Schedule.”) Replace worn pins as needed.

lubricate at regular intervals (Refer to Section 2.6, “Lubrication Schedule.”)

5. Boom will not raise or lower. 1. Broken hydraulic hoses or tubes and/or connection leaks.

2. Lift/lower hydraulic system not operating properly.

3. Faulty Lift cylinders. 3. Repair cylinder. (Refer to

4. Seized boom pivot pin bushing. 4. Replace bushing.

3.14

1. Locate break, replace hose(s) or tube(s), tighten connections.

2. Refer to Section 8, “Hydraulic System.”

Section 8.11.4, “Cylinder Inspection.”)

G5-18A/2505

Boom

Boom Troubleshooting (Continued)

Problem Cause Remedy

6. Rapid boom pad wear. 1. Incorrect wear pad gap. 1. Check wear pad gaps and

correct as needed. Refer to Section 3.4.2, “Boom Wear Pad Replacement.”

7. Auxiliary hydraulics will not operate.

2. Rapid cycle times with heavy loads.

3. Contaminated, corroded or rusted wear pad sliding surfaces.

4. Operating in extremely dusty/ abrasive conditions.

1. Auxiliary hydraulic system not operating properly.

2. Reduce cycle times.

3. Remove contamination and/or corrosion from wear pad sliding surfaces and lubricate. If the surfaces cannot be reconditioned, replace the boom section(s).

4. Clean equipment frequently.

1. Refer to Section 8, “Hydraulic System.”

G5-18A/2505

3.15

Boom

This Page Intentionally Left Blank

3.16

G5-18A/2505

Section 4

Cab and Covers

Contents

PARAGRAPH TITLE PAGE

4.1 Operator’s Cab and Covers Component Terminology. . . . . . . . . . . . . . . . . . . . . 4.2

4.2 Operator’s Cab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.2.1 Operator’s Cab Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.2.2 Serial Number Decal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.3 Cab Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.3.1 Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3

4.3.2 Steering Column/Valve Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4

4.3.3 Brake Pedal and Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4

4.3.4 Throttle Pedal Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5

4.3.5 Joystick Assembly Replacement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7

4.3.6 Windshield Wiper Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7

4.3.7 Windshield Washer Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7

4.3.8 Heater/Defroster System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7

4.4 Cab Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8

4.5 Cab Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9

G5-18A/2505

4.1

Cab and Covers

4.1 OPERATOR’S CAB AND COVERS COMPONENT TERMINOLOGY

To understand the safety, operation and maintenance information presented in this section, it is necessary that the operator/mechanic be familiar with the names and locations of the major assemblies of the machine cab and covers. The following illustration identifies the components that are referred to throughout this section.

LSI INDICATOR

(2505)

SPEEDOMETER

FRAME LEVEL

INDICATOR

HORN BUTTON

(2505)

ACCESSORY CONTROL

LEVER (IF EQUIPPED)

JOYSTICK

STEERING WHEEL

INSTRUMENT

PANEL

PARK BRAKE

SWITCH (G5-18A)

LSI OVERRIDE

SWITCH (2505)

TRANSMISSION

CONTROL LEVER

QUICK ATTACH SWITCH

SERVICE BRAKE PEDAL

STEERING COLUMN

ADJUSTER

(IF EQUIPPED)

RIGHT HAND CONSOLE

IGNITION SWITCH

ACCELERATOR PEDAL

4.2

PARK BRAKE LEVER (2505)

MY2390

G5-18A/2505

WARNING

DO NOT service the machine without following all

safety precautions as outlined in the “Safety Practices” section of this manual. Failure to follow the safety practices could result in death or serious injury.

4.2 OPERATOR’S CAB

4.2.1 Operator’s Cab Description

The welded metal cab features a modular design, allowing for a relatively quick, simple exchange of the entire cab and/or component parts. The cab is bolted directly to the frame.

The operator’s cab is a protective structure. The cab itself contains rollover protective and falling object protective structures (ROPS/FOPS) for the operator.

DO NOT weld, grind, drill, repair or modify the cab in any way. Any modification or damage to cab structural components requires cab replacement. The lives of the operator and others are potentially at stake.

To help ensure optimum safety, protection and performance, replace the cab if it is damaged. Refer to the appropriate parts manual for ordering information.

The cab contains the seat, operating controls, numerous panels, steering and brake components, and more.

Covers and mirrors on the machine exist for safety, protection and appearance. They are relatively simple to remove and replace.

Cab and Covers

4.3 CAB COMPONENTS

4.3.1 Steering Wheel

a. Steering Wheel Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Remove the battery negative (-) cable from the battery negative (-) terminal.

5. Carefully pry the center button (1) out of the steering wheel.

6. Mark the steering wheel and shaft to ensure proper installation. Remove the nut (2) securing the steering wheel (3) to the splined steering column shaft.

7. Use a steering wheel puller to remove the steering wheel (3) from the splined shaft.

4.2.2 Serial Number Decal

The cab serial number decal is located inside the cab, under the seat. Information specified on the serial number plate includes the cab model number, the cab serial number and other data. Write this information down in a convenient location to use in cab correspondence.

G5-18A/2505

MAH0430

b. Steering Wheel Installation

1. Install the steering wheel (3) onto the splined steering column shaft.

2. Secure the steering wheel with the nut (2).

3. Press the center button (1) onto the steering wheel.

4. Connect the battery negative (-) cable to the battery negative (-) terminal.

5. Close and secure the engine covers.

4.3

Cab and Covers

4.3.2 Steering Column/Valve Replacement

a. Steering Column and Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. Remove the steering wheel (1) (Refer to Section

4.3.1, “Steering Wheel.”), transmission control lever (2) and accessory lever (if equipped)(3).

6. Loosen and remove the steering column cover.

7. Loosen and remove the dash cover.

8. Label, disconnect and cap the hydraulic hoses (4) and fittings on the steering orbitrol valve (5).

b. Steering Column and Valve Installation

1. Install the four hex-flange capscrews (three if machine is equipped with tilt column) through the steering column, mounting bracket and into the top of the orbitrol valve.

Note: ALWAYS use new o-rings when servicing the machine.

2. Uncap and install new o-rings into the fittings. Lubricate the o-rings with clean hydraulic oil.

3. Uncap and reconnect the previously labeled hydraulic hoses to their appropriate locations.

4. Install the dash cover.

5. Install the steering column cover.

6. Install the steering wheel (Refer to Section 4.3.1, “Steering Wheel.”), accessory lever and transmission control lever.

7. Connect the battery negative (-) cable to the battery negative (-) terminal.

8. Carefully examine all connections one last time before engine start-up. Rectify any faulty conditions.

9. Start the engine and check the operation of all controls. Check for fluid leaks. Check the hydraulic fluid level in the tank and add fluid as required.

10. Close and secure the engine covers.

MY2440

9. Remove the four hex-flange capscrews (three if machine is equipped with tilt column) connecting the orbitrol valve to the steering column.

10. Pull the steering column assembly and orbitrol valve from the machine cab.

Note: DO NOT disassemble the steering orbitrol valve. The steering orbitrol valve is not serviceable and must be replaced in its entirety, if defective.

c. Power Steering Test

Conduct a pressure check of the steering hydraulic circuits at the test port on the implement pump. Refer to Section 8.5.5, “Steering Pressure Checking.”

4.3.3 Brake Pedal and Valve

a. Brake Valve Removal

Refer to Section 8.10.2, a. “Service Brake Valve Removal,” for removal information.

b. Brake Valve Installation

Refer to Section 8.10.2, b. “Service Brake Valve Installation,” for installation information.

c. Service Brake Pedal Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

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Cab and Covers

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. Remove the lower dash panel.

MY2400

4.3.4 Throttle Pedal Replacement

a. Throttle Pedal Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. Remove the nut from the end of the throttle cable (8).

6. Loosen the hex jam nut and flat washer (9) securing the throttle cable to the throttle pedal assembly.

7. Remove three capscrews, three lockwashers and three washers (10) securing the throttle pedal assembly to the cab frame.

8. Remove the throttle pedal assembly from the cab.

6. Remove the clip/pin (6) from the brake plunger fork link.

7. Remove the pin (7) and the return spring securing the service brake pedal to the cab.

8. Remove the service brake pedal from the cab.

d. Service Brake Pedal Installation

1. Position the service brake pedal in its mounting location within the cab.

2. Install the brake pedal being careful to reposition the brake plunger yoke. Install the return spring and pin. Install clip/pin in brake plunger fork link.

3. Adjust the brake pedal as needed.

4. Install and secure the lower dash cover.

5. Connect the battery negative (-) cable to the battery negative (-) terminal.

6. Close and secure the engine covers.

7. Install and secure the lower dash panel.

8. Connect the battery negative (-) cable to the battery negative (-) terminal.

Note: Check for leaks, and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

MY2360

9. Close and secure the engine covers.

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Cab and Covers

b. Throttle Pedal Installation

1. Align the throttle pedal assembly with its mount holes under the cab dash.

2. Install three capscrews securing the throttle pedal assembly to the mount. Torque the capscrews to 9 lb-ft (12 Nm).

3. Tighten the hex jam nut and flat washer (1) securing the throttle cable to the throttle pedal assembly.

4. Install the nut to the end of the throttle cable (2).

5. Connect the battery negative (-) cable to the battery negative (-) terminal.

6. Close and secure the engine cover.

c. Throttle Adjustment

1. From within the cab, lightly depress the accelerator pedal (3) to the full-throttle position.

2. With the accelerator pedal held in the full throttle position, check the throttle position on the fuel injector pump on the engine. The throttle lever should be bottomed against the limit-stop screw.

3. If there is an adjustment needed, return to the cab and adjust the throttle cable (4) so the lever on the fuel injector pump bottoms against the limit-stop just before the throttle pedal bottoms against the limitstop (5) in the cab.

NOTICE

During the full throttle check:

• DO NOT operate any hydraulic function.

• DO NOT steer or apply any pressure to the steering wheel.

• Keep the transmission in (N) NEUTRAL.

4. Check the engine rpm at full throttle. If the rpm is not 2370 ±50 rpm, readjust the throttle cable at the throttle pedal within the cab.

4.6

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Cab and Covers

4.3.5 Joystick Assembly Replacement

a. Joystick Assembly Removal

1. Park the machine on a firm, level surface, fully retract the boom, raise the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Support the boom by installing the lift cylinder lock or a suitable support.

4. Open the engine covers. Allow the system fluids to cool.

5. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

6. Above the hydraulic reservoir, label, disconnect and cap the hydraulic hoses and electrical connections (6) to the joystick assembly.

7. Lift the rubber boot (7) from base of the joystick assembly and remove the four capscrews (8).

8. Remove the joystick assembly.

4.3.6 Windshield Wiper Assembly

Refer to Section 9.9.1, “Windshield Wiper Motor,” for removal and installation information.

4.3.7 Windshield Washer Assembly

Refer to Section 9.9.3, “Windshield Washer Reservoir and Pump,” for removal and installation information.

4.3.8 Heater/Defroster System

a. Heater Assembly Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

MY2410

b. Joystick Assembly Installation

1. Uncap and reconnect the previously labeled hydraulic hoses to their appropriate locations.

2. Reconnect the electrical connections.

3. Install the four capscrews in the joystick base.

4. Reseat the rubber boot to the joystick base.

5. Remove the lift cylinder lock if previously installed.

6. Connect the battery negative (-) cable to the battery negative (-) terminal.

7. Test the boom joystick functions:

Test the boom joystick functions to ensure they match the control pattern on the joystick decal located inside cab.

CAUTION

The cooling system is under pressure, and escaping coolant can cause severe burns and eye injury. To prevent personal injury, NEVER remove the radiator cap while the cooling system is hot. Wear safety glasses. Turn the radiator cap to the first stop and allow pressure to escape before removing the cap completely. Failure to follow the safety practices could result in death or serious injury.

5. Place a suitable container beneath the radiator drain plug or petcock. Slowly turn the cap on the coolant overflow bottle to allow any pressure to escape. Remove the overflow bottle cap.

6. Place a funnel at the base of the radiator to channel the drained coolant into the container. Open the radiator drain plug or petcock and allow the coolant to drain. Replace the drain plug, or close the petcock.

7. Transfer the coolant into a suitable, covered container, and label as "Used Coolant". Dispose of used coolant at an approved recycling facility.

Note: Label all hoses to ensure correct installation.

8. Remove the front cover from the cab to expose the heater/defroster element (9).

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4.7

Cab and Covers

9. Loosen the hose clamps and disconnect the two heater hoses.

MY2430

10. Remove the capscrews, nuts and lockwashers securing the heater assembly to the cab.

11. Carefully pull out the heater assembly (10). Label and disconnect the wiring harness connections at the blower.

12. Remove the heater assembly.

b. Heater Assembly Installation

1. Install the heater assembly (10) to its original orientation.

2. Connect the wiring harness connections at the blower.

3. Install the capscrews, nuts and lockwashers to secure the heater assembly to the cab.

4. Reconnect the two heater hoses.

5. Refill the cooling system at the coolant overflow bottle with a 50/50 mixture of ethylene glycol and water allowing time for the coolant to fill the engine block. See Section 2.4, “Fluids, Lubricants and Capacities,” for system capacities.

6. Connect the battery negative (-) cable at the battery negative (-) terminal.

7. Start the engine, run it briefly at low idle and check the machine for any visual sign of fluid leakage. STOP the machine immediately if any leakage is noted, and make any necessary repairs before continuing.

8. Install the front cover (9) in the cab.

9. Check the coolant level. Add or remove fluid as required.

10. Close and secure the engine covers.

4.4 CAB REMOVAL

Note: Replace the cab if it is damaged. Refer to the appropriate parts manual for ordering information.

Before performing any inspection, maintenance or service operation, thoroughly clean the machine. DO NOT spray water or cleaning solution in, on, near or around the operator’s dash panels and electrical components.

Inspect the cab, its welds and mounts. If modification, damage, a cracked weld and/or fatigued metal is discovered, replace the cab. Contact your local JLG distributor with any questions about the suitability or condition of a cab.

Note: Remove and label cab components as needed before removing the cab from the machine. Label, disconnect and cap hydraulic hoses. Transfer cab parts to the replacement cab after the replacement cab is securely mounted on the machine.

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Block the wheels to ensure that the machine does not move.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

Note: Steps 5 through 8 are only required if machine is equipped with heating or heating/air conditioning.

5. Place a suitable container beneath the radiator drain plug or petcock. Slowly turn the cap on the coolant overflow bottle to allow any pressure to escape. Remove the overflow bottle cap.

7. Transfer the coolant into a suitable, covered container, and label as "Used Coolant". Dispose of used coolant at an approved recycling facility.

Note: Label all hoses to ensure correct installation.

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Cab and Covers

8. Loosen the hose clamps, and disconnect the heater hoses from the engine. Cap or plug the hoses to prevent debris from entering the heater system.

9. Disconnect the cab-to-wiring harness connectors.

Note: Record the location, and label all cables to ensure correct installation.

10. Working underneath the cab, label and disconnect the hydraulic hoses at the cab fittings. Plug the hoses and cap the fittings.

11. In the cab, disconnect the throttle cable at the throttle lever bracket. Route the cable away from the cab to prevent damage during removal.

12. Install four lifting eye bolts with a suitable lifting capacity in the existing holes at the top corners of the cab (1).

13. Remove the cab-to-frame bolts (2), washers and nuts.

MY2420

14. Carefully begin to lift the cab. Stop and check that all wiring, hydraulic hoses and fasteners are disconnected or removed. Do not damage the fuel fill tube.

15. When all wiring, hydraulic hoses and fasteners are disconnected or removed, carefully and slowly lift the cab and remove it from the frame. Readjust the position of the sling as needed to help balance the cab during removal.

16. When the cab is completely clear of the machine, carefully lower it to the ground. Block up or support the cab.

17. Inspect the condition of the fittings, clamps, hydraulic hoses, etc. Replace parts as indicated by their condition.

18. Inspect and replace other machine parts that are exposed with the cab removed. Repair or replace as required.

4.5 CAB INSTALLATION

1. Block all four wheels to help prevent the machine from moving. Assure that there is sufficient overhead and side clearance for cab installation.

2. Attach a sling with suitable lifting capacity through the previously installed eye bolts.

3. Use a hoist or overhead crane and sling attached to the cab. Carefully begin to align the cab with the mounting holes in the frame. Stop and check that wiring, hydraulic hoses, cables, etc., will not be pinched or damaged as the cab is positioned. Take special note of the fuel fill tube as well. Readjust the position of the sling as needed to help balance the cab during installation.

4. Install the cab-to-frame bolts, washers and nuts (2). Torque the upper cab bolts to 340 lb-ft (461 Nm). Torque the lower cab bolts to 530 lb-ft (719 Nm).

5. Remove the eye bolts from the top of the cab (1).

6. Connect the throttle cable to the throttle bracket in the cab.

7. Uncap and reconnect the hydraulic hoses at the cab locations.

8. Secure the throttle cable to the hydraulic hoses using nylon ties.

9. Uncap and connect the heater hoses to the engine. Secure with hose clamps.

10. Install the cab-to-wiring harness connectors on side of the cab.

11. Fill the cooling system completely with a 50/50 mixture of ethylene glycol and water, allowing time for the coolant to fill the engine block. The cooling system capacity is listed in Section 2.4, “Fluids, Lubricants and Capacities.”

12. Connect the battery negative (-) cable to the battery negative (-) terminal.

13. Carefully examine all cab components, fasteners, etc., one last time before engine start-up. Rectify any faulty conditions.

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4.9

Cab and Covers

14.Start the engine and check the operation of all controls. Check for hydraulic fluid leaks. Check the hydraulic

fluid level in the tank and add fluid as required.

NOTICE

When the engine is initially started, run it briefly at low idle and check the machine for any visual sign of fluid leakage. STOP the engine immediately if any leakage is noted, and make any necessary repairs before continuing.

15.Wait for the engine to cool and check the coolant level. Add coolant to the overflow bottle as required to bring the coolant to the proper level.

16. Close and secure the engine covers.

4.10

G5-18A/2505

Section 5

Axles, Drive Shafts, Wheels and Tires

Contents

PARAGRAPH TITLE PAGE

5.1 Axle, Drive Shaft and Wheel Component Terminology. . . . . . . . . . . . . . . . . . . . 5.2

5.2 General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3 Axle Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3.1 Axle Serial Number Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3.2 Axle Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3.3 Axle Internal Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3.4 Axle Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3

5.3.5 Axle Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4

5.3.6 Axle Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5

5.3.7 Axle Assembly and Drive Shaft Troubleshooting . . . . . . . . . . . . . . . . . . . 5.6

5.4 Drive Shafts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.4.1 Drive Shaft Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.4.2 Drive Shaft Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.4.3 Drive Shaft Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.4.4 Drive Shaft Cleaning and Drying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.4.5 Drive Shaft Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9

5.5 Wheels and Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.10

5.5.1 Removing Wheel and Tire Assembly from Machine. . . . . . . . . . . . . . . . . 5.10

5.5.2 Installing Wheel and Tire Assembly onto Machine . . . . . . . . . . . . . . . . . . 5.11

5.6 Steering Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

5.6.1 Steering Angle Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

5.7 Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

5.7.1 Brake Disk Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

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5.1

Axles, Drive Shafts, Wheels and Tires

5.1 AXLE, DRIVE SHAFT AND WHEEL COMPONENT TERMINOLOGY

To understand the safety, operation and maintenance information presented in this section, it is necessary that the operator/mechanic be familiar with the names and locations of the major assemblies of the axles, drive shafts, wheels and tires. The following illustration identifies the components that are referred to throughout this section.

FRONT AXLE

ASSEMBLY

STEERING CYLINDER

(FRONT)

DRIVE SHAFT

STEERING CYLINDER

(REAR)

MY2070

REAR AXLE ASSEMBLY

5.2

G5-18A/2505

5.2 GENERAL INFORMATION

Before performing any inspection, maintenance or service operation, thoroughly clean the unit. The axles and drive shafts should be checked and repaired only by experienced service technicians who are aware of all safety instructions and particular component features.

Use suitable products to thoroughly clean all disassembled mechanical parts to help prevent personal injury to the worker and prevent damage to the parts. Carefully inspect the integrity of all moving parts (bearings, yokes, tubes, gears, shafts, etc.) and fasteners (nuts, bolts, washers, etc.) as they are subject to major stress and wear. Always replace elastic locknuts and any damaged, worn, cracked, seized or otherwise improper parts that could affect the safe and proper functioning of the machine, axles and drive shafts.

5.3 AXLE ASSEMBLIES

5.3.1 Axle Serial Number Plate

The axle serial number plate is located on the inside of the right yoke. Information on the serial number plate is required in correspondence regarding the axle.

Supply information from the axle serial number plate when communicating about an axle assembly or axle components.

5.3.2 Axle Specifications

General axle specifications are found in Section 2, “General Information and Specifications.” Axle (differential housing) fluid information is found in Section

2.4, “Fluids, Lubricants and Capacities.”

5.3.3 Axle Internal Service

Detailed axle service instructions (covering the axle, differential, brakes and wheel-end safety, repair, disassembly, reassembly, adjustment and troubleshooting information) are provided in the following manual. For internal axle service instructions and detailed specifications contact your local JLG distributor for a copy of the Dana-Spicer Repair Manual (P/N 31200419).

Axles, Drive Shafts, Wheels and Tires

WARNING

DO NOT service the machine without following all

safety precautions as outlined in the “Safety Practices” section of this manual. Failure to follow the safety practices could result in death or serious injury.

5.3.4 Axle Maintenance

CLEANING: Clean parts with machined or ground

surfaces (such as gears, bearings and shafts) with emulsion cleaners or petroleum-based cleaners. DO NOT steam clean internal components and the interior of the planetary hub and axle housing. Water can cause corrosion of critical parts. Rust contamination in the lubricant can cause gear and bearing failure. Remove old gasket material from all surfaces.

DRYING: Use clean, lintless towels to dry components after cleaning. DO NOT dry bearings by spinning them with compressed air; this can damage mating surfaces due to lack of lubrication. After drying, lightly coat components with oil or a rust-preventive chemical to help protect them from corrosion. If storing components for a prolonged period, wrap them in wax paper.

PERIODIC OPERATION REQUIREMENT: Every two weeks, drive the machine far enough to cause the drivetrain components to make several complete revolutions. This will help ensure that internal components receive lubrication to minimize deterioration caused by environmental factors such as high humidity.

SUBMERSION: If the machine has been exposed to water deep enough to cover the hubs, disassemble the wheel ends and inspect for water damage and contamination. If the carrier housing was submerged in water, especially if the water level was above the vent tube (breather), drain the axle and inspect internal parts for water damage and contamination. Before assembling and refilling the unit with the specified lubricant(s), clean, examine and replace damaged parts as necessary.

Note: Use a suitable puller for bearing removal. Clean, inspect and lubricate all bearings just prior to reassembly. If replacement of a damaged bearing cup or

cone is necessary, replace the cup and cone as a set.

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5.3

Axles, Drive Shafts, Wheels and Tires

5.3.5 Axle Removal

WARNING

An improperly supported machine can fall, causing death or severe personal injury. Safely raise and adequately support the machine so that it will remain stable and in place before attempting to remove an axle. Failure to follow the safety practices could result in death or serious injury.

The front and rear axle assemblies differ in that the front axle assembly is equipped with a drop box, hydraulic drive pump, parking brake mechanism and a limited-slip feature; the rear axle has none of these. The following steps outline a typical axle removal procedure, suitable for either the front or the rear axle assembly.

Cleanliness is extremely important. Before attempting to remove the axle, thoroughly clean the machine. Avoid spraying water or cleaning solution on the stabilizer solenoids and other electrical components. If using a steam cleaner, seal all openings before steam cleaning.

MY2090

Note: Clear the work area of all debris, unnecessary personnel, etc. Allow sufficient space to raise the machine and to remove the axle.

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. If the axle will be disassembled after removal, the oil will have to be drained. Loosen the breather to release possible internal pressure, then tighten breather with a torque wrench to 9 lb-ft (12 Nm).

6. If the axle will be disassembled after removal, place a suitable receptacle under the axle (1), drop box (2) and wheel hubs (3) drain plugs. Remove the drain plugs and allow the axle oil to drain into the receptacle. Transfer the used axle oil into a suitable covered container, and label the container as "Used Oil." Dispose of the used oil at an approved recycling facility.

MY2080

7. Label, disconnect and cap the steering and brake lines at the axle. Wipe up any spilled oil.

8. Block the front and rear of both tires on the axle that is not being removed. Ensure that the machine will remain in place during axle removal before proceeding.

9. Raise the machine using a suitable jack or hoist. Place suitable supports under both sides of the frame and lower the machine onto the supports. Ensure that the machine will remain in place during axle removal.

10. Support the axle that is being removed with a suitable jack, hoist or overhead crane and sling. DO NOT raise the axle or the machine.

11. Mark and remove both wheel and tire assemblies from the axle that is being removed. (Refer to Section 5.5.1, “Removing Wheel and Tire Assembly from Machine.”)

Note: The wheel and tire assemblies must be re-installed later with the directional tread pattern “arrows” facing in the direction of forward travel.

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Axles, Drive Shafts, Wheels and Tires

12. Remove the drive shaft assembly. (Refer to Section

5.4.3, “Drive Shaft Removal.”)

13. Remove the capscrews, locknuts and axle plates securing the axle to the frame.

14. Remove the axle from the machine using the jack, hoist or overhead crane and sling supporting the axle. DO NOT raise or otherwise disturb the machine while removing the axle. Balance the axle and prevent it from tipping, turning or falling while removing it from beneath the machine. Place the axle on a suitable support or holding stand.

5.3.6 Axle Installation

1. Before proceeding, ensure that the machine will remain in place during axle installation. Block the front and rear of both tires on the axle that is already installed on the machine.

2. If applicable, raise the machine using a suitable jack or hoist. Place suitable supports beneath the frame and lower the machine onto the supports, allowing enough room for axle installation. Ensure that the machine will remain in place during axle installation.

3. Using a suitable jack, hoist or overhead crane and sling, remove the axle from its support or holding stand. Balance the axle and prevent it from tipping, turning or falling while positioning it beneath the machine. DO NOT raise or otherwise disturb the machine while installing the axle. Keep the axle supported and balanced on the jack, hoist or overhead crane and sling throughout the installation procedure.

4. Position the axle under the frame, and align with the holes in the frame.

5. Install the axle with capscrews, locknuts and the axle plates. Torque the front and rear axles to 420 lb-ft (569 Nm).

6. Install the drive shaft assemblies. (Refer to Section

5.4.5, “Drive Shaft Installation.”)

7. If reinstalling an axle previously removed from the machine, position the driveshaft yoke on the axle according to the alignment marks made earlier. If installing a new axle, note the position of the driveshaft yoke at the transmission. Align the driveshaft yoke on the axle in the same plane as the yoke on the transmission.

8. Tighten the axle oil drain plug (1), loosen and remove the axle oil fill plug (4). Tighten the drop box oil drain plug (2), loosen and remove the drop box oil fill plug (5).Fill axle with the appropriate oil. Refer to Section 2.4, “Fluids, Lubricants and Capacities,” for proper oil and capacities.

9. Rotate wheel hubs 90 degrees so the drain plug (3) becomes the fill plug. Fill wheel hubs with the appropriate oil. Refer to Section 2.4, “Fluids, Lubricants and Capacities,” for proper oil and capacities.

10. Install the wheel and tire assemblies. (Refer to Section 5.5.2, “Installing Wheel and Tire Assembly onto Machine.”)

11. Carefully remove the jack, hoist or overhead crane and sling supporting the axle.

12. Carefully raise the machine using a suitable jack or hoist. Remove the supports from beneath the frame and lower the machine to the ground.

13. Remove the blocks from the front and rear of both tires on the other axle.

14. Uncap and reconnect the steering and brake lines at their axle fittings. Refer to Section 8.10.4, “Brake Test,” for brake bleeding procedures.

15. Check the hydraulic reservoir oil level.

16. Connect the battery negative (-) cable to the battery negative (-) terminal.

17. Close and secure the engine covers.

18. Start the engine. Turn the steering wheel several times lock to lock and check the function of the brakes. Check for hydraulic leaks, and tighten or

repair as necessary.

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5.5

Axles, Drive Shafts, Wheels and Tires

5.3.7 Axle Assembly and Drive Shaft Troubleshooting

Problem Cause Remedy

1. Excessive axle noise while driving.

1. Oil level too low. 1. Fill oil to correct level. (Refer to Section 2.4, “Fluids, Lubricants and Capacities.”)

2. Axle and/or wheel end housings

filled with incorrect oil or oil level low.

3. Incorrect alignment of ring and

pinion gears.

4. Incorrect pinion (input) shaft

bearing preload.

5. Worn or damaged bearings. 5. Replace bearings as needed.

6. Worn or broken gear teeth. 6. Replace gears as needed.

7. Contamination in the axle. 7. Drain axle and/or wheel end

2. Drain axle and/or wheel end housings and fill to correct level with Mobilfluid® 424 Tractor Hydraulic Fluid. (Refer to Section 2.4, “Fluids, Lubricants and Capacities.”)

3. Correct alignment by adding or removing shims as needed.

4. Correct bearing preload by adding or removing shims as needed.

housings and fill to correct level with Mobilfluid® 424 Tractor Hydraulic Fluid. (Refer to Section 2.4, “Fluids, Lubricants and Capacities.”)

2. Intermittent noise when traveling.

3. Vibration or intermittent noise when traveling.

8. Axle housing damaged. 8. Replace damaged parts.

1. Universal joint(s) worn or damaged.

2. Differential ring and/or pinion gears damaged.

1. Drive shaft universal joint(s) assembly incorrectly tightened.

2. Drive shaft universal joint(s) worn or damaged.

3. Drive shaft damaged/ unbalanced.

1. Repair or replace universal joints as needed.

2. Determine cause and repair as needed.

1. Tighten capscrews to correct torque.

2. Repair or replace universal joints as needed.

3. Replace drive shaft as needed.

5.6

G5-18A/2505

Axles, Drive Shafts, Wheels and Tires

5.3.7 Axle Assembly and Drive Shaft Troubleshooting (Continued)

Problem Cause Remedy

4. Oil leaking from axle (differential housing and/or axle housings).

1. Drain plugs loose and/or o-rings damaged or missing.

2. Hose fittings loose. 2. Tighten fittings.

3. Axle shaft seal damaged or missing and/or worn or damaged shaft sealing surfaces.

4. Input shaft multi-seal ring damaged or missing and/or worn or damaged pinion (input) shaft sealing surfaces.

5. Axle casing to brake housing and/or brake housing to differential assembly o-rings and/or seals worn or damaged.

6. Axle housing mounting nuts and capscrews loose.

7. Differential and/or axle housing(s) damaged.

1. Replace o-rings as needed and tighten plugs 59 lb-ft (80 Nm).

3. Replace seal and/or joint coupling fork shaft (axle shaft).

4. Replace multi-seal ring and/or input shaft. Adjust ring and pinion alignment and bearing preload as described in the Dana Repair Manuals.

5. Replace o-rings and seals.

6. Tighten housing nuts and capscrews to 236 lb-ft (320 Nm).

7. Replace housing(s) as needed.

5. Oil leaking from wheel end housing (planet carrier).

6. Oil leaking from steering cylinder.

1. Oil level plugs loose and/or o-rings damaged or missing.

2. O-ring between hub and housing (planet carrier) damaged or missing.

3. Shaft seal damaged or missing and/or worn or damaged shaft sealing surfaces.

4. Housing capscrews loose. 4. Tighten housing capscrews to

5. Housing (planet carrier) damaged. 5. Replace housing (planet carrier).

1. Hose fittings loose. 1. Tighten fittings.

2. Steering cylinder o-rings and/or seals worn or damaged.

3. Piston rod seal worn or damaged.

4. Cylinder tube damaged. 4. Replace cylinder tube.

1. Replace o-rings as needed and tighten plugs to 59 lb-ft (80 Nm).

2. Replace o-ring.

3. Replace seal and/or fork joint shaft.

41 lb-ft (55 Nm).

2. Replace o-rings and seals.

3. Replace piston rod seal.

G5-18A/2505

5.7

Axles, Drive Shafts, Wheels and Tires

5.3.7 Axle Assembly and Drive Shaft Troubleshooting (Continued)

Problem Cause Remedy

7. Axle overheating. 1. Oil level too high. 1. Fill oil to correct level with

Mobilfluid® 424 Tractor Hydraulic Fluid. (Refer to Section 2.4, “Fluids, Lubricants and Capacities.”)

2. Axle and/or wheel end housings filled with incorrect oil or oil contaminated or oil level low.

8. High steering effort required. 1. Steering (hydraulic) system not operating properly.

2. Excessive joint housing swivel bearing preload.

3. Worn or damaged swivel bearings.

9. Slow steering response. 1. Steering (hydraulic) system not operating properly.

2. Steering cylinder leaking internally.

10. Excessive noise when brakes are engaged.

1. Brake discs worn. 1. Check brake discs for wear.

2. Drain axle and/or wheel end housing and fill to correct level with Mobilfluid® 424 Tractor Hydraulic Fluid. (Refer to Section 2.4, “Fluids, Lubricants and Capacities.”)

1. Refer to the appropriate Dana Repair Manual.

2. Correct bearing preload by adding or removing shims as needed.

3. Replace swivel bearings as needed.

1. Refer to the appropriate Dana Repair Manual.

2. Repair or replace steering cylinder as needed.

Refer to appropriate Dana Repair Manual.

2. Brake discs damaged. 2. Replace brake discs.

11. Brakes will not engage. 1. Brake (hydraulic) system not operating properly.

2. Brake piston o-rings and seals damaged (leaking).

12. Brakes will not hold the machine or braking power reduced.

5.8

1. Brake discs worn. 1. Check brake discs for wear.

2. Brake (hydraulic) system not operating properly.

3. Brake piston o-rings and seals damaged (leaking).

1. Refer to the appropriate Dana Repair Manual.

2. Replace o-rings and seals.

Refer to the appropriate Dana Repair Manual.

2. Refer to the appropriate Dana Repair Manual.

3. Replace o-rings and seals.

G5-18A/2505

Axles, Drive Shafts, Wheels and Tires

5.4 DRIVE SHAFTS

5.4.1 Drive Shaft Inspection

Whenever servicing the machine, conduct a visual inspection of the drive shaft and cross and bearing assembly (universal joints, or U-joints). A few moments spent doing this can help prevent further problems and down time later.

Inspect area where the drive shaft flange yoke and slip yoke mount to the drive shaft. Attempt to turn drive shaft in both directions. Look for excessive looseness, missing parts, cracks or other damage. Worn or damaged drive shaft and cross and bearing assembly may cause an excessive amount of vibration or noise.

5.4.2 Drive Shaft Maintenance

Refer to Section 2.6, “Lubrication Schedule,” for information regarding the lubrication of the grease fittings on the drive shafts.

5.4.3 Drive Shaft Removal

Note: To help ensure optimum performance, the drive shaft assemblies are specially balanced as a unit at the factory. When servicing, order a complete assembly if components are bent or damaged. Refer to the appropriate parts manual for ordering information.

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. The drive shaft assembly is a balanced assembly. Mark the yoke and axle, transmission and the shaft and slip yoke so that these components can be returned to their original positions when reinstalled. Yokes at both ends of the drive shaft must be in the same plane to help prevent excessive vibration.

6. Remove the four capscrews (1) and four locknuts securing the yoke flange (2) to the front axle flange.

7. Remove the four capscrews securing the flange yoke to the rear axle flange.

8. Remove the drive shaft assembly (3).

TO FRONT

TO REAR

AXLE

MAH0450

5.4.4 Drive Shaft Cleaning and Drying

1. Disassemble and clean all parts using an approved cleaning fluid. Allow to dry.

2. Remove any burrs or rough spots from all machined surfaces. Re-clean and dry as required.

5.4.5 Drive Shaft Installation

1. Raise the drive shaft assembly (3) into position. The slip-yoke end of the drive shaft mounts toward the front axle. If reinstalling a drive shaft previously removed, align the flange yokes according to the alignment marks made during removal.

Note: Yokes at both ends of the drive shaft must be in the same plane to help prevent excessive vibration.

2. Install the four capscrews (1) and four locknuts securing the yoke flange (2) to the front axle.

Loctite 102 lb-ft (139 Nm).

3. Install the four capscrews securing the bearing crosses to the rear axle. Loctite capscrews to 102 lb-ft (139 Nm).

4. Connect the battery negative (-) ground cable at the battery negative (-) terminal.

5. Close and secure the engine covers.

and torque the capscrews to

and torque the

G5-18A/2505

5.9

Axles, Drive Shafts, Wheels and Tires

5.5 WHEELS AND TIRES

WARNING

Mismatched tire sizes, ply ratings or mixing of tire types (radial tires with bias-ply tires) may compromise machine stability and may cause machine to tip over. Failure to follow the safety practices could result in death or serious injury.

JLG recommends a replacement tire to be the same size, ply and brand as originally installed. Refer to the appropriate parts manual for ordering information. If not using a JLG approved replacement tire, JLG recommends that replacement tires have the following characteristics:

• Equal or greater ply/load rating and size of original.

• Tire tread contact width equal or greater than

original.

• Wheel diameter, width and offset dimensions equal to the original.

• Approved for the application by the tire manufacturer (including inflation pressure and maximum tire load).

The rims installed have been designed for stability requirements which consist of track width, tire pressure and load capacity. Size changes such as rim width, center piece location, larger or smaller diameter, etc., without written factory recommendations, may result in unsafe condition regarding stability.

The tires are filled with air only when the machine leaves the factory. JLG does not recommend the use of hydrofill as a tire-fill substance because of possible environmental impact.

Large-bore valve stems are used to help expedite tire inflation and deflation. An inner tube may be used if a tire does not provide an airtight seal. Check tire inflation pressures when the tires are cold. When mounting a tire on the wheel, the tire must be mounted on the wheel respective of the directional tread pattern of the tire; this produces a left or right tire and wheel assembly.

The wheel and tire assemblies must be installed with the directional tread pattern “arrows” (1) facing in the direction of forward travel.

MAH0890

5.5.1 Removing Wheel and Tire Assembly from Machine

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Loosen but DO NOT remove the lug nuts on the wheel and tire assembly to be removed.

4. Place a suitable jack under the axle pad closest to the wheel being removed. Raise the machine and position a suitable support beneath the axle. Allow sufficient room to lower the machine onto the support and to remove the wheel and tire assembly.

5. Lower the machine onto the support.

6. Remove lug nuts and lug washers in an alternating pattern.

7. Remove the wheel and tire assembly from the machine.

5.10

G5-18A/2505

Axles, Drive Shafts, Wheels and Tires

5.5.2 Installing Wheel and Tire Assembly onto Machine

Note: The wheel and tire assemblies must be installed with the directional tread pattern “arrows” facing in the direction of forward travel.

Tread “arrows” must

point forward

Install tires onto

wheels to rotate in

proper direction

MAH0460

5.6 STEERING ADJUSTMENT

5.6.1 Steering Angle Adjustment

Steering angle adjustment instructions can be found in the appropriate Dana Repair Manual.

5.7 BRAKES

5.7.1 Brake Disk Inspection.

Check the brake disks for wear every 1,000 hours of operation or yearly.

The service brakes can only be checked by performing a teardown of the axle. Refer to the appropriate Dana Repair Manual for complete teardown instructions. The minimum tolerance for the brake disc gap is 0.016 in (4,10 mm).

1. Position wheel onto studs on wheel end of axle.

2. Install wheel lug washers.

3. Start all nuts by hand to prevent cross threading. DO NOT use a lubricant on threads or nuts.

4. Tighten lug nuts in an alternating pattern as indicated in figure. Torque to 221 lb-ft (300 Nm).

OAH0990

5. Remove machine from supports.

G5-18A/2505

5.11

Axles, Drive Shafts, Wheels and Tires

This Page Intentionally Left Blank

5.12

G5-18A/2505

Section 6

Transmission

Contents

PARAGRAPH TITLE PAGE

6.1 Transmission Assembly Component Terminology . . . . . . . . . . . . . . . . . . . . . . . 6.2

6.2 Transmission Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.3 Transmission Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.3.1 Transmission Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.4 Transmission Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.4.1 Transmission Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.4.2 Transmission Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4

6.4.3 Transmission Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4

6.4.4 After Transmission Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4

6.5 Transmission Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5

6.5.1 Filter Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5

6.5.2 Filter Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5

6.6 Towing a Disabled Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6

G5-18A/2505

6.1

Transmission

6.1 TRANSMISSION ASSEMBLY COMPONENT TERMINOLOGY

To understand the safety, operation and maintenance information presented in this section, it is necessary that the operator/mechanic be familiar with the names and locations of the major assemblies of the transmission. The following illustration identifies the components that are referred to throughout this section.

HYDROSTATIC

TRANSMISSION

REVERSE

RELIEF

VALV E

DIRECTIONAL

CONTROL VALVE

HYDROSTATIC

FILTER

FORWARD

RELIEF

VALV E

6.2

MY1920

G5-18A/2505

Transmission

6.4 TRANSMISSION REPLACEMENT

WARNING

DO NOT service the machine without following all

safety precautions as outlined in the “Safety Practices” section of this manual. Failure to follow the safety practices could result in death or serious injury.

6.2 TRANSMISSION DESCRIPTION

Instructions in this section pertain mainly to general specifications, towing, maintenance information, and transmission removal and installation procedures. For internal transmission service instructions and detailed specifications contact your local JLG distributor for a copy of the Rexroth Repair Manual (P/N 31200124).

More information can be obtained from the serial number plate directly mounted on the transmission. Information specified on the serial number plate includes the transmission model number, the transmission serial number and other data. Information on the serial number plate is required in correspondence regarding the transmission.

6.3 TRANSMISSION SPECIFICATIONS

6.3.1 Transmission Maintenance

The transmission is a hydraulic component and requires the same maintenance as the hydraulic system. Refer to Section 2.5, “Maintenance Schedules.”

Performance criteria is based on full throttle engine speed unless otherwise specified or not applicable.

NOTICE

DO NOT use flushing compounds for cleaning purposes.

Note: Contact your local JLG distributor if internal transmission repair is required during the warranty period.

Note: To help ensure safety and optimum performance, replace the transmission if it is damaged. Refer to the appropriate parts manual for ordering information.

Cleanliness is of extreme importance. Before attempting to remove the transmission, thoroughly clean the exterior of the transmission to help prevent dirt from entering during the replacement process. Avoid spraying water or cleaning solution onto or near the transmission shift solenoids and other electrical components.

6.4.1 Transmission Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, turn rear wheels to give easier access to rear of engine compartment, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. Remove the air cleaner assembly.

6. Remove hood support at rear of engine.

7. Drain the hydraulic oil reservoir. Refer to Section

8.7.2, “Hydraulic Oil Reservoir Draining.”

8. Label, disconnect and cap all hydraulic hoses attached to transmission, cap all fittings and openings to keep dirt & debris from entering hydraulic system.

9. Label and disconnect all electrical connections attached to the transmission.

10. Wipe up any spilled hydraulic oil.

G5-18A/2505

6.3

Transmission

11. Vertically secure transmission with a lifting strap or chain. Use a suitable hoist or overhead crane. Operate the hoist or crane to remove slack from the chain, but DO NOT raise the transmission at this time.

12. Remove the two Allen head bolts that attach the transmission to the engine.

WARNING

The transmission may move while hoisting it out of the chassis. Carefully move the transmission and adjust the sling as needed. Keep fingers, hands, legs and other body parts clear of the transmission. Failure to follow the safety practices could result in death or serious injury.

13. Carefully remove the transmission from the machine. Avoid causing damage to the transmission or surrounding parts.

14. Lift the transmission clear of the machine, and lower it onto suitable supports or secure it to a stand built especially for transmission or engine service. Secure the transmission so that it will not move or fall.

6.4.2 Transmission Disassembly

Transmission disassembly, internal inspection, service, repair and assembly procedures are covered in the Rexroth Repair Manual (P/N 31200124).

6.4.3 Transmission Installation

7. Reinstall the air cleaner assembly.

8. Reconnect battery cables to terminals, starting with the positive (+) terminal.

9. Close and secure the engine covers.

6.4.4 After Transmission Replacement

1. Install new hydraulic filters.

2. Check the hydraulic oil level and add oil as required.

NOTICE

DO NOT use flushing compounds for cleaning purposes.

3. Reassemble all components and fill the hydraulic reservoir with clean, fresh oil. DO NOT overfill.

4. Run the engine for two minutes at idle to help bleed any air from the hydraulic system.

5. Operate all boom functions to ensure any air is removed from the hydraulic system.

6. Retract and level the boom, recheck the level of the fluid in the reservoir.

7. Add oil as necessary to bring the fluid level up until it reaches the FULL mark on the reservoir. Recheck the oil level when it reaches operating temperature (180-200° F or 83-94° C).

8. Recheck all drain plugs, lines, connections, etc., for leaks, and tighten where necessary.

WARNING

NEVER lift a transmission alone; enlist the help of at

least one assistant or use a suitable hoist or overhead crane and sling. Failure to follow the safety practices could result in death or serious injury.

1. Use a lifting strap or chain attached to a hoist or overhead crane to position the transmission within the chassis.

2. Insert the two Allen head bolts that attach the transmission to the engine. Torque to 154 lb-ft (210 Nm).

3. Remove the hoist or overhead crane and sling.

4. Uncap and reconnect the previously labeled hoses and electrical connections to their appropriate locations.

5. Fill hydraulic reservoir and bleed the system.

6. Reinstall the hood support.

6.4

G5-18A/2505

Transmission

6.5 TRANSMISSION FILTER REPLACEMENT

The hydrostatic pump filter is located on the left (inside) of the pump (1).

MY2450

Cleanliness is of extreme importance. Before attempting to remove the transmission filter, thoroughly clean the exterior of the transmission to help prevent dirt from entering during the replacement process. Avoid spraying water or cleaning solution onto or near the transmission direction solenoids and other electrical components.

6.5.2 Filter Installation

1. Clean the area surrounding the hydraulic pump filter.

2. Install a new o-ring (5) on the base of the filter housing and lubricate the new o-ring with clean hydraulic oil.

3. Install the small end of the filter spring (4) into the filter base.

4. Install the filter (3) into the filter base (6) directly behind the filter spring.

6.5.1 Filter Removal

2. Place an Do Not Operate Tag on both the ignition key switch and steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Disconnect the battery negative (-) cable at the battery negative (-) terminal.

5. Remove the air cleaner assembly.

6. To allow easier access to the filter, label, disconnect and cap all hydraulic hoses in the filter area, cap all fittings and openings to keep dirt & debris from entering hydraulic system.

7. Place a container or shop rags below the filter housing to contain any spilled hydraulic oil.

8. Using a 15/16 in. (25 mm) wrench, loosen and remove the filter housing (2), filter (3) and spring (4).

5. Slowly screw the filter housing into the filter base keeping the filter and housing aligned.

6. Torque the filter housing to 33 lb-ft (45 Nm).

7. Uncap and reconnect the previously labeled hoses to their appropriate locations.

8. Fill hydraulic reservoir and bleed the system.

9. Reinstall the air cleaner assembly.

10. Reconnect battery cables to terminals, starting with the positive (+) terminal.

11. Close and secure the engine covers.

G5-18A/2505

6.5

Transmission

6.6 TOWING A DISABLED MACHINE

Towing a disabled machine should only be attempted as a last resort, after exhausting all other options. Make every effort to repair the machine, and move it under its own power.

Towing is only possible by using the “towing” feature built into the hydrostatic pump and disengaging the park brake on the front axle.

1. Securely block all four wheels.

WARNING

BLOCK ALL FOUR WHEELS TO PREVENT MACHINE FROM MACHINE ROLL AWAY. Failure

to follow the safety practices could result in death or serious injury.

2. Connect an external pump to the P1 port (1) on the front axle and apply 220-435 psi (15-30 bar) to release the park brake.

3. Loosen the unlocking bolts (2) and remove the stop washers.

4. Tighten the unlocking bolts, bottoming the bolts against the axle housing.

5. Release the pressure from the external pump and remove pump.

6. Loosen the jam nut and turn the forward relief valve (3) on the hydrostatic transmission counterclockwise three turns.

7. Carefully remove the blocking from each tire and tow the machine to a secure location.

Note: This procedure does not alter any relief settings.

MY1930

2 (Not Shown)

MY2050

WARNING

BLOCK ALL FOUR WHEELS TO PREVENT MACHINE FROM MACHINE ROLL AWAY. Failure

to follow the safety practices could result in death or serious injury.

8. After the machine has been towed to a secure location, reactivate the parking brake.

9. Block all four wheels.

10. Turn the forward relief valve (3) on the hydrostatic transmission clockwise three turns and tighten the jam nut.

6.6

11. Connect an external pump to the P1 port (1) on the front axle and apply 220-435 psi (15-30 bar) to the park brake.

12. Loosen the unlocking bolts (2) and install the stop washers.

13. Tighten the unlocking bolts.

14. Release the pressure from the external pump and remove pump.

15. The parking brake should now be reactivated and the front wheels locked.

16. Remove the blocks from the four tires.

17. Verify that the parking brake works.

Note: If the parking brake does not work, check all activation operations step by step.

G5-18A/2505

Section 7

Engine: Perkins 1104D-44T

Contents

PARAGRAPH TITLE PAGE

7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2

7.1.1 Disclaimer and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2

7.1.2 Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2

7.2 Engine Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.3 Specifications and Maintenance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.4 Engine Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.4.1 Radiator Pressure Cap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4

7.4.2 Radiator/Oil Cooler and Coolant Heater Replacement . . . . . . . . . . . . . . . 7.4

7.5 Engine Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5

7.6 Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5

7.6.1 Diesel Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5

7.6.2 Fuel/Hydraulic Oil Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6

7.6.3 After Fuel System Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6

7.7 Engine Exhaust and Air Cleaner System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7

7.8 Engine Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7

7.8.1 Engine Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.7

7.8.2 Engine Disassembly, Inspection and Service . . . . . . . . . . . . . . . . . . . . . . 7.8

7.8.3 Engine Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8

7.9 Engine Coupler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.9.1 Coupler Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.9.2 Coupler Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.10 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.10

G5-18A/2505

7.1

Engine: Perkins 1104D-44T

7.1 INTRODUCTION

7.1.1 Disclaimer and Scope

These instructions are written for worldwide use. In territories where legal requirements govern engine smoke emission, noise, safety factors, etc., apply all instructions, data and dimensions provided herein in such a way that after maintenance, service and repair of the engine, engine operation does not violate local regulations.

Note: These instructions cover only the routine maintenance, removal, installation and troubleshooting of the engine. For assistance with comprehensive engine diagnosis, repair and component replacement, contact your local Perkins Service partner.

A gradual running-in (break-in) of a new engine is not necessary. Full load can be applied to a new engine as soon as the engine is put into service and the coolant temperature is at least 140° F (60° C). Extended lightload operation during the early life of the engine is not recommended. DO NOT run the engine at high, no-load speeds. DO NOT apply an overload to the engine.

7.1.2 Component Terminology

To understand the safety, operation and maintenance information presented in this section, it is necessary that the operator/mechanic be familiar with the names and locations of the engine components. The following illustration identifies the components that are referred to throughout this section.

7.2

G5-18A/2505

Engine: Perkins 1104D-44T

THERMOSTAT

IMPLEMENT

PUMP

OIL FILTER

FUEL FILTER

AIR CLEANER

ASSEMBLY

STARTER

HYDROSTATIC

TRANSMISSION

ENGINE

MOUNT

TURBOCHARGER

MY1900

ALTERNATOR

FAN

ENGINE

MOUNT

G5-18A/2505

7.3

Engine: Perkins 1104D-44T

7.2 ENGINE SERIAL NUMBER

The Perkins 1104D-44T serial number is located on a tag on top of the engine. Information contained in the serial number is required in correspondence with the engine manufacturer.

Supply the engine serial number and/or data tag information when communicating about an engine or engine components.

7.3 SPECIFICATIONS AND MAINTENANCE INFORMATION

For engine, coolant and oil specifications, and maintenance information, refer to Section 2, “General Information and Specifications.”

Note: Detailed Perkins engine service instructions (covering disassembly, inspection, internal repair, assembly, adjustment and troubleshooting information) are provided in the appropriate Perkins engine service manual.

7.4 ENGINE COOLING SYSTEM

7.4.1 Radiator Pressure Cap

For a 230° F (110° C) system, use a 13 psi (95 kPa) radiator cap. An incorrect or malfunctioning cap can result in the loss of coolant and a hot-running engine.

7.4.2 Radiator/Oil Cooler and Coolant Heater Replacement

Before considering radiator or oil cooler replacement for other than obvious damage, conduct a cooling system pressure test check the coolant specific gravity, coolant level, fan belt tension and dash panel temperature indicator.

• If the engine runs hot, check the temperature of the upper radiator hose.

• If the hose is not hot, the thermostat may be stuck in the closed position.

• If the engine has overheated, performance may suffer, indicating other damage including a leaking cylinder head gasket, cracked cylinder head or block, and/or other internal engine damage.

a. Radiator/Oil Cooler Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the

machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

4. Thoroughly clean the engine and surrounding area, including all hoses and fittings before proceeding.

5. Disconnect the battery negative (-) cable from the battery negative (-) terminal.

6. Remove radiator cover and support (1).

7. Slowly turn the coolant overflow bottle cap and allow any pressure to escape. Remove the overflow bottle cap.

8. Place a suitable container beneath the radiator petcock.

7.4

G5-18A/2505

Engine: Perkins 1104D-44T

9. Place a funnel at the base of the radiator to channel the drained coolant into the container. Open the radiator petcock and drain the coolant into the funnel. Transfer the fluid into a properly labeled container. Dispose of properly if coolant needs to be replaced. Close the radiator petcock.

10. Label, disconnect and cap all coolant hoses attached to the radiator. Cap all fittings and openings to keep dirt & debris from entering the cooling system.

11. Label, disconnect and cap all hydraulic hoses attached to the radiator. Cap all fittings and openings to keep dirt & debris from entering the hydraulic system.

12. Detach the fan safety shroud.

b. Radiator/Oil Cooler Installation

1. Install the isolator mounts to the bottom of the radiator. Insert radiator through the machine frame and secure to the radiator mount plate with new locknuts.

2. Be sure the engine fan has clearance in regard to the radiator. Install the engine cover support (1) to the frame and radiator.

3. Attach the fan safety shroud.

4. Uncap and reconnect the previously labeled hydraulic hoses to the appropriate locations.

5. Uncap and reconnect all previously labeled coolant hoses to the appropriate locations.

6. Fill the coolant overflow bottle with a 50/50 mixture of ethylene glycol and water.

7. Connect the battery negative (-) cable to the battery negative (-) terminal.

8. Run the engine to operating temperature. Visually check for leaks with the engine running. Check the coolant level in the overflow bottle and fill, or drain, as necessary. Check the hydraulic fluid level in the tank and add fluid as required.

9. Install the radiator cover.

10. Close and secure the engine cover.

MY1910

13. Remove the locknuts holding the isolator mounts at the bottom of the machine.

14. Connect a lifting strap to the radiator/oil cooler and carefully lift the radiator/oil cooler out of the engine bay.

7.5 ENGINE ELECTRICAL SYSTEM

The engine electrical system, including the starter, alternator and primary wiring, is described in Section 9, “Electrical System.”

7.6 FUEL SYSTEM

7.6.1 Diesel Fuel

Fuel represents a major portion of machine operating costs and therefore must be used efficiently. ALWAYS use a premium brand of high-quality, clean diesel fuel. Low cost, inferior fuel can lead to poor performance and expensive engine repair.

Note: Use only diesel fuel designed for diesel engines. Some heating fuels contain harmful chemicals that can seriously affect engine efficiency and performance.

G5-18A/2505

7.5

Engine: Perkins 1104D-44T

NOTICE

Due to the precise tolerances of diesel injection systems, keep the fuel clean, and free of dirt and water. Dirt and water in the fuel system can cause severe damage to both the injection pump and the injection nozzles. Use ASTM #2 diesel fuel with a minimum Cetane rating of 40. #2 diesel fuel gives the best economy and performance under most operating conditions. Fuels with Cetane numbers higher than 40 may be needed in high altitudes or extremely low ambient temperatures to help prevent misfiring and excessive smoking.

Inform the owner/operator of the machine to use #2 diesel fuel, unless ambient temperatures are below 32° F (0° C). When temperatures are below 32° F (0° C), a blend of #1 diesel and #2 diesel fuels (known as “winterized” #2 diesel) may be used.

Note: #1 diesel fuel may be used, however, fuel economy will be reduced.

To clean the fuel/hydraulic oil tank:

1. Have a dry chemical (Class B) fire extinguisher near the work area.

2. Depending on which side of the tank is contaminated (fuel or hydraulic oil), remove the fuel or oil tank drain plug, and safely drain any fuel or hydraulic oil into a suitable container. Dispose of fuel or hydraulic oil properly.

3. Clean the fuel/hydraulic oil tank with a high-pressure washer, or flush the tank with hot water for five minutes and drain the water. Dispose of contaminated water properly.

4. For the fuel tank side, add a diesel fuel emulsifying agent to the tank. Refer to the manufacturer’s instructions for the correct emulsifying agent-towater mixture ratio. Refill the tank with water, and agitate the mixture for 10 minutes. Drain the tank completely. Dispose of contaminated water properly.

5. Refill the fuel tank with water until it overflows. Completely flush the tank with water. Empty the fuel tank, and allow it to dry completely.

c. Inspection

WARNING

DO NOT mix gasoline or alcohol with diesel fuel. The

mixture can cause an explosion. Failure to follow the safety practices could result in death or serious injury.

Use a low-sulfur content fuel with a cloud point (the temperature at which wax crystals form in diesel fuel) at least 10° below the lowest expected fuel temperature. The viscosity of the fuel must be kept above 1.3 centistrokes to provide adequate fuel system lubrication.

Note: When using diesel fuel with a sulfur content below

1.3 percent, the filter change interval must be reduced by 75 hours. The use of fuel with a sulfur content above

1.3 percent is not recommended.

7.6.2 Fuel/Hydraulic Oil Tank

a. Cleaning and Drying

If contaminated fuel, hydraulic oil or foreign material is in the tank, the tank can usually be cleaned.

b. If a leak is suspected between the fuel and hydraulic oil

tank, contact your local JLG distributor.

Note: If a leak is suspected between the fuel and hydraulic oil tank, contact your local JLG distributor.

1. Inspect the fuel/hydraulic oil tank thoroughly for any cracks, slices, leaks or other damage.

2. Plug all openings except one elbow fitting. Install the elbow fitting, and apply approximately 0.07-0.10 bar (1-1.5 psi) of air pressure through the elbow. Check the tank for leaks by applying a soap solution to the exterior and look for bubbles to appear at the cracked or damaged area.

d. Disassembly and Assembly

The fuel/hydraulic oil reservoir is a one piece-unit integral to the chassis frame and cannot be disassembled.

7.6.3 After Fuel System Service

1. Drain and flush the fuel tank if it was contaminated.

2. Fill the fuel tank with fresh, clean diesel fuel as required.

Note: If bleeding of the fuel system is required, contact your local Perkins Service Partner.

7.6

G5-18A/2505

Engine: Perkins 1104D-44T

7.7 ENGINE EXHAUST AND AIR CLEANER SYSTEM

WARNING

Avoid breathing exhaust fumes, and prevent engine operation from becoming a cause of toxic emissions. Failure to follow the safety practices could result in death or serious injury.

CAUTION

Exhaust system components reach high temperatures and can cause severe burns. DO NOT come into contact with hot exhaust system components. Failure to follow the safety practices could result in death or serious injury.

When the exhaust or air cleaner systems are removed be sure to cover any open ports to prevent dirt and debris from contaminating engine components.

NOTICE

NEVER run the engine with only the inner safety element installed. Serious engine damage could occur if air cleaner elements are not properly installed.

7.8 ENGINE REPLACEMENT

7.8.1 Engine Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

4. Thoroughly clean the engine and surrounding area, including all hoses and fittings before proceeding.

5. Disconnect the battery negative (-) cable from the battery negative (-) terminal.

6. Remove the engine cover, radiator cover and engine bay access cover.

7. Remove front and rear engine cover supports.

8. Drain hydraulic reservoir. Refer to Section 8.7.2, “Hydraulic Oil Reservoir Draining.”

9. Drain radiator and overflow bottle. Refer to Section

7.4.2, “Radiator/Oil Cooler and Coolant Heater Replacement.”

10. Label, disconnect and cap all hydraulic hoses attached to engine and radiator, cap all fittings and plug hoses to keep dirt & debris from entering hydraulic system.

11. Disconnect the fuel inlet (1) and return lines. Install a plug in the end of each line.

12. Remove hydraulic and fuel filters, and filter bracket assembly.

13. Unbolt and remove the fan safety shroud.

14. Remove bolts securing the radiator and lift it clear of engine compartment. Refer to section Section 7.4.2, “Radiator/Oil Cooler and Coolant Heater Replacement.”.

15. Mark the engine fan orientation. Remove the engine fan.

G5-18A/2505

7.7

Engine: Perkins 1104D-44T

7.8.2 Engine Disassembly, Inspection and

Engine disassembly, internal inspection, service, repair and assembly procedures are covered in the Perkins 1104D-44T service manual. Several special engine service tools are required to properly service the Perkins engine.

Contact your local Perkins Service partner for further information.

Note: If the engine is being replaced, there may be external components that will be required to be transferred from the original engine to the replacement engine depending upon

who you purchase the new engine from and the configuration of your replacement engine. Refer to the appropriate Perkins user manual for detailed procedures that cover the transfer of original engine components to the

MY1890

replacement engine.

Service

16. Label and disconnect all wire connections on the engine.

17. Mark the location of the throttle cable (2) at the engine throttle lever. Disconnect the throttle cable.

18. Detach exhaust and air cleaner hoses from the engine. Cover air inlets to protect from dirt & debris.

19. Remove air cleaner assembly from engine compartment.

20. Completely disconnect exhaust pipe.

21. Remove the hydraulic reservoir fill tube.

22. Secure the engine with a lifting strap or chain from the appropriate lifting points (3). Use a suitable hoist or overhead crane.

23. Remove the 4 motor mount bolts that attach the engine to the frame.

24. Carefully lift the engine from the machine. Avoid causing damage to the surrounding parts.

25. Lift the engine clear of the machine, and lower it onto suitable supports or stand. Secure the engine so that it will not move or fall.

7.8.3 Engine Installation

Note: Refer to Section 2.2, “Torques,” for specific fastener torque specifications.

1. Position engine in engine compartment being sure to line up the 4 motor mount holes. Replace bolts and torque to 71 lb-ft (97 Nm).

2. Connect the hydraulic reservoir fill tube.

3. Connect the exhaust pipe to the engine.

4. Install the air cleaner assembly into the engine compartment and attach hose to air intake.

5. Reconnect throttle cable (2) onto the engine, if necessary adjust for full travel.

6. Reattach any previously labeled wire connections on the engine.

7. Attach the engine fan.

8. Reinstall the front and rear engine cover supports.

9. Secure the radiator with the necessary bolts and attach the fan safety shroud. Check that the fan top clearance is adequate with regard to the radiator. Reattach the previously labeled hoses. Refer to Section 7.4.2, “Radiator/Oil Cooler and Coolant Heater Replacement.” Fill with a 50/50 mixture of ethylene glycol and water.

10. Install the filter bracket assembly. Secure the hydraulic and fuel filters.

11. Connect the fuel inlet line to the fuel filter (1) and reconnect the return fuel line to the engine.

12. Uncap and reconnect all hydraulic hoses and fittings to the engine and necessary hydraulic elements. Keep hoses free of dirt & debris.

7.8

G5-18A/2505

Engine: Perkins 1104D-44T

13. Refill the hydraulic reservoir (Refer to the appropriate Operation & Safety Manual for information concerning the hydraulic oil and filter change).

14. Reinstall the engine cover, radiator cover and engine bay access cover.

MY1890

15. Reconnect the battery terminals, being sure to start with the positive (+) terminal.

16. Check that all hydraulic, electrical, cooling, fuel and exhaust system connections are correct and connected tightly.

17. Run engine to normal operating temperature then shut off the engine. While the engine is cooling, check for leaks.

18. Allow the engine to cool. Check the radiator coolant level, and top off with a 50/50 mixture of ethylene glycol and water. Replace the radiator cap.

19. Check for leaks from the engine, main hydraulic pump and lines, transmission, hydraulic reservoir and fuel tank. Check the levels of all fluids and lubricants. Fill

as required.

20. Obtain and connect an appropriate engine analyzer or tachometer. Check the engine rpm at full throttle. If the rpm is not 2370 ±50 rpm, readjust the throttle limit-stop screw at the throttle pedal within the cab.

21. Purge the hydraulic system of air by operating all boom functions through their entire range of motion several times. Check the hydraulic oil level.

22. Check for proper operation of all components.

23. Turn the engine OFF.

24. Install the belly pan.

25. Install the engine cover. Close and secure the cover.

7.9 ENGINE COUPLER

7.9.1 Coupler Removal

1. Remove Hydrostatic transmission. Refer to Section

6.4.1, “Transmission Removal.” Be sure to follow all described safety guidelines.

2. After transmission has been removed, take out the 12 bolts that attach the Flywheel Cover Plate to the engine.

3. Pull off the Flywheel Cover Plate to expose the coupler assembly (3).

4. Remove the necessary bolts to detach the coupler assembly.

NOTICE

During the full throttle check:

• DO NOT operate any hydraulic function.

• DO NOT steer or apply any pressure to the steering wheel.

• Keep the transmission in NEUTRAL (N).

G5-18A/2505

MY2550

7.9.2 Coupler Installation

1. Attach the coupler assembly (3) using the necessary bolts. Torque to 155 lb-ft (210 Nm).

2. Bolt on the Flywheel Cover Plate over the coupler and flywheel. Torque bolts to 37 lb-ft (50 Nm).

3. Reattach the hydrostatic transmission. Follow all guidelines in Section 6.4.3, “Transmission Installation.”

7.9

Engine: Perkins 1104D-44T

7.10 TROUBLESHOOTING

Trouble Possible Causes (see key, below)

Low Cranking Power

Will Not Start

Difficult Starting

Lack of Power

Misfiring

Excessive Fuel Consumption

Black Exhaust

Blue/White Exhaust

Low Oil Pressure

Knocking

Erratic Running

Vibration

High Oil Pressure

Overheating

Excessive Crankcase Pressure

Poor Compression

Starts and Stops

1, 2, 3, 4

5, 6, 7, 8, 9, 10, 12, 13, 14, 17, 18, 19, 20, 22, 31, 32, 33

5, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 21, 22, 24, 29, 31, 32, 33

8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 31, 32, 33

8, 9, 10, 12, 13, 14, 18, 19, 20, 25, 26, 28, 29, 30, 32

11, 13, 14, 16, 18, 19, 20, 22, 23, 24, 25, 27, 28, 29, 31, 32, 33

11, 13, 14, 16, 18, 19, 20, 22, 24, 25, 27, 28, 29, 31, 32, 33

4, 18, 19, 20, 25, 27, 31, 33, 34, 35, 45, 56

4, 36, 37, 38, 39, 40, 42, 43, 44, 58

9, 14, 18, 19, 22, 26, 28, 29, 31, 33, 35, 36, 45, 46, 59

7, 8, 9, 10, 11, 12, 13, 14, 20, 21, 23, 26, 28, 29, 30, 33, 35, 45, 59

13, 14, 20, 23, 25, 26, 29, 30, 33, 45, 47, 48, 49

4, 38, 41

11, 13, 14, 18, 19, 24, 25, 45, 50, 51, 52, 53, 54, 57

15, 25, 31, 33, 34, 45, 55

11, 19, 25, 28, 29, 31, 32, 33, 34, 46, 59

10, 11, 12

Key to Possible Causes

1. Battery charge low

2. Bad electrical connection

3. Faulty starter motor

4. Incorrect grade of lubricating oil

5. Low cranking speed

6. Fuel tank empty

7. Faulty stop control operation

8. Fuel inlet restricted

9. Faulty fuel lift pump

10. Clogged fuel filter

11. Restricted air cleaner

12. Air in fuel system

13. Faulty fuel injection pump

14. Faulty fuel injectors or incorrect type

15. Exhauster or vacuum pipe leak

16. Induction system leaks

17. Broken fuel injection pump drive

18. Incorrect fuel pump timing

19. Incorrect valve timing

20. Poor compression

21. Blocked fuel tank vent

22. Incorrect grade of fuel

23. Sticking throttle or restricted movement

24. Exhaust pipe restriction

25. Leaking cylinder head gasket

26. Overheating

27. Cold running

28. Incorrect tappet adjustment

29. Sticking valves

30. Incorrect high pressure pipes

31. Worn cylinder bores

32. Pitted valves and seats

33. Broken, worn or sticking piston ring(s)

34. Worn valve stems and guides

35. Restricted air cleaner

36. Worn or damaged bearings

37. Insufficient oil in sump

38. Inaccurate gauge

39. Oil pump worn

40. Pressure relief valve sticking open

41. Pressure relief valve sticking closed

42. Broken relief valve spring

43. Faulty suction pipe

44. Restricted oil filter

45. Piston seizure/pick up

46. Incorrect piston height

47. Damaged fan

48. Faulty engine mounting

49. Incorrectly aligned flywheel housing or incorrectly aligned flywheel

50. Faulty thermostat

51. Restriction in water jacket

52. Loose fan belt

53. Restricted radiator

54. Faulty water pump

55. Restricted breather pipe

56. Damaged valve stem oil deflectors (if fitted)

57. Coolant level too low

58. Blocked sump strainer

59. Broken valve spring

7.10

G5-18A/2505

Section 8

Hydraulic System

Contents

PARAGRAPH TITLE PAGE

8.1 Hydraulic Component Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3

8.2 Safety Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.4 Hoses, Tube Lines, Fittings, Etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.4.1 Replacement Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.4.2 Hose, Tube, Line and Fitting Replacement . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.5 Hydraulic Pressure Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5

8.5.1 Pressure Checks and Adjustments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.5

8.5.2 Main Control Valve Pressure Checking. . . . . . . . . . . . . . . . . . . . . . . . . . . 8.6

8.5.3 Charge Pressure Checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.6

8.5.4 Boom Function Pressure Checking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.6

8.5.5 Steering Pressure Checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.7

8.6 Hydraulic Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.8

8.6.1 G5-18A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.8

8.6.2 2505 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.9

8.6.3 Auxiliary Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.10

8.7 Hydraulic Reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.7.1 Pressurized Hydraulic Oil Fill Cap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.7.2 Hydraulic Oil Reservoir Draining. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.7.3 Hydraulic Oil Reservoir Filling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.8 Hydraulic System Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.8.1 Implement Pump Failure Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.8.2 Implement Pump Replacement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11

8.9 Front Drive Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.13

8.10 Valves and Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.14

8.10.1 Main Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.14

8.10.2 Service Brake Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.15

8.10.3 Parking Brake Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.16

8.10.4 Brake Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.17

8.10.5 Steering Orbitrol Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.17

8.10.6 Pilot Select Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.17

8.10.7 Inching Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.18

8.10.8 Steer Select Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.19

8.10.9 Joystick Enable Valve (CE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.21

8.10.10 Load Stability Indicator Valve (CE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.22

G5-18A/2505

8.1

Hydraulic System

8.11 Hydraulic Cylinders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.23

8.11.1 General Cylinder Removal Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . 8.23

8.11.2 General Cylinder Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.23

8.11.3 Cylinder Cleaning Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

8.11.4 Cylinder Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

8.11.5 General Cylinder Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

8.11.6 General Cylinder Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.25

8.11.7 Steering Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.25

8.11.8 Hydraulic Cylinder Torque Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 8.26

8.2

G5-18A/2505

8.1 HYDRAULIC COMPONENT TERMINOLOGY

To understand the safety, operation and service information presented in this section, it is necessary that the operator/mechanic be familiar with the name and location of the hydraulic components of the machine. The following illustration identifies the components that are referred to throughout this section.

COMPENSATING

CYLINDER

Hydraulic System

HYDRAULIC RESERVOIR and

LIFT/LOWER CYLINDER

(UNDER BOOM)

MAIN CONTROL

VALV E

IMPLEMENT

PUMP

HYDRAULIC

FILTER

HYDROSTATIC

DRIVE PUMP

STEERING CYLINDER

EXTEND/RETRACT

CYLINDER

TILT CYLINDER

FRONT AXLE

DRIVE MOTOR

MY2530

G5-18A/2505

8.3

Hydraulic System

8.2 SAFETY INFORMATION

WARNING

DO NOT service the machine without following all

safety precautions as outlined in the “Safety Practices” section of this manual. Failure to follow the safety practices could result in death or serious injury.

Petroleum-based hydraulic fluids are used in this machine. The temperature of hydraulic fluid increases during the operation of various hydraulic functions. A heated petroleum-based hydraulic fluid presents a fire hazard, especially when an ignition source is present.

Accordingly, periodically inspect all hydraulic system components, hoses, tubes, lines, fittings, etc. Carefully examine any deterioration and determine whether any further use of the component would constitute a hazard. If in doubt, replace the component.

Whenever you disconnect a hydraulic line, coupler, fitting or other component, slowly involved. A hissing sound or slow seepage of hydraulic fluid may occur in most cases. After the hissing sound has ceased, continue removing the part. Any escaping oil should be directed into an appropriate container. Cap or otherwise block off the part to prevent further fluid seepage.

Hydraulic system maintenance will, at times, require that the engine be operated. Always follow safety precautions.

A major cause of hydraulic component failure is contamination. Keeping the hydraulic fluid as clean as possible will help avoid downtime and repairs. Sand, grit and other contaminants can damage the finely machined surfaces within hydraulic components. If operating in an exceptionally dirty environment, change filters and inspect the fluid more often. When servicing the system, cap or plug hydraulic fittings, hoses and tube assemblies. Plug all cylinder ports, valves and the hydraulic reservoir, and pump openings until installation occurs. Protect threads from contamination and damage.

Some hydraulic functions are actuated by interfacing with electrical system components (switches, solenoids and sensors). When the hydraulic system is not functioning properly, check the electrical aspect of the malfunctioning circuit also.

8.3 SPECIFICATIONS

Refer to Section 2.3, “Specifications,” for hydraulic system specifications.

and cautiously loosen the part

8.4 HOSES, TUBE LINES, FITTINGS, ETC.

There are numerous hydraulic hoses, tubes, fittings, etc. used on this machine. Periodically inspect all of these and carefully examine any signs of wear, abrasion and/or deterioration. Determine whether any further use of the component would constitute a hazard. If in doubt, replace the component.

8.4.1 Replacement Considerations

Conditions including, but not limited to, the following are sufficient for considering component replacement:

1. Any evidence of hydraulic fluid leakage at the surface of a flexible hose or its junction with the metal and couplings.

2. Any blistering or abnormal deformation to the outer covering of a hydraulic hose.

3. Hydraulic oil leakage at any threaded or clamped joint that cannot be eliminated by normal tightening or other recommended procedures.

4. Evidence of excessive abrasion or scrubbing on the outer surface of a hose, rigid tube, or hydraulic fitting. Modification must be made to eliminate the interference of the elements in contact with one another, or to otherwise protect the components from contact with one another. Slightly moving a hose or adjusting a plastic tie wrap may often be all that is necessary to eliminate interference; evaluate each situation and proceed as required by the individual circumstances.

8.4.2 Hose, Tube, Line and Fitting Replacement

Before removing a hydraulic hose or component, always mark or otherwise label the related parts and the exact location of the hose or component to aid in proper reinstallation. Hydraulic fluid is a good cleaner and can remove most liquid-ink type markings, so make sure the mark or label will remain intact. Alternative methods to using markers include color-coded tie wraps, number-tag sets, alpha-numeric stampings or markings, and suitably labeled pieces of tape. Select an appropriate marking method for the conditions and proceed accordingly.

NEVER replace a hydraulic hose or other component with a part not specifically designed for this machine. Use only factory approved parts for best performance and safety.

Removal and replacement of hoses, tube lines, fittings, etc. usually involves straightforward procedures. When removing a hydraulic hose or other component, be aware that o-rings are used throughout the hydraulic system.

8.4

G5-18A/2505

Hydraulic System

ALWAYS replace a used o-ring with a new part.

Check all routing of hoses, wiring and tubing for sharp bends or interference with any rotating members. Install appropriate protective devices such as tie wraps and conduit to help shield hoses from damage. All tube and hose clamps must be tight.

8.5 HYDRAULIC PRESSURE DIAGNOSIS

JLG Parts Department has a kit available to use for hydraulic system maintenance and troubleshooting: the JLG Pressure Test Kit. The kit is contained in a durable polyethylene carrying case for demanding field service conditions.

Pressure Test Kit

The hydraulic pressure test kit is used to pressure test the various hydraulic components in the hydraulic system. The kit includes:

• Gauges for testing high and low pressure circuits

• Fittings, couplers and hoses

MZ1460

Contact JLG Parts Department at 717-485-6472 for ordering information.

8.5.1 Pressure Checks and Adjustments

In general, follow the steps below whenever conducting pressure checks and performing adjustments:

1. Park the machine on a firm, level surface. Engage the park brake, place the transmission control lever in (N) NEUTRAL, place the neutral lock lever in the (N) NEUTRAL LOCK position, level the boom and turn the engine OFF.

2. Pressure tee fittings are conveniently located in each hydraulic circuit. Install a pressure gauge capable of measuring at least 10% more pressure than that which the circuit being checked operates under.

3. Start the engine. Operate machine functions several times to allow hydraulic oil to reach operating temperature. The hydraulic oil temperature should be between 100-120° F (38-49° C). If a temperature gauge or thermometer is unavailable, the hydraulic oil reservoir should be warm to the touch.

4. Fully depress the accelerator pedal as required. Place and hold the joystick in the position needed to operate the particular machine function being checked. Continue holding the joystick in position until pressure readings are taken.

5. Check the pressure gauge reading. It should read as described in the appropriate section. If the reading is not as specified, turn the engine OFF and check other components in the system. Verify that all related hydraulic components and electrical switches, sensors, solenoids, etc. are operating correctly.

6. As a last resort, adjust the appropriate relief valve, if applicable. Turning the adjustment screw clockwise will increase the pressure; turning the screw counterclockwise will decrease the pressure.

Start the engine and check the pressure again. Turn the engine OFF, operate the auxiliary hydraulic control lever (on units equipped with the optional auxiliary hydraulic system), then disconnect or remove the pressure gauge from the machine.

Part

Number

70000652 Hydraulic Pressure Test Kit 10 lbs. Consult Factory

70000101 Digital Hydraulic Pressure

G5-18A/2505

Description Approximate

Weight

7 lbs. Consult Factory

Test Kit

Price and

Availability

8.5

Hydraulic System

8.5.2 Main Control Valve Pressure Checking

Attach 5000 psi (345 bar) gauge to the test port (1) at the rear of the implement pump to check the system pressure. Make sure the gauge is visible from inside the cab.

MY2540

See Section 8.5.1, “Pressure Checks and Adjustments,” for start up procedure. Check the main control pressure with the park brake on and the service brake off at full throttle. Retract a boom circuit function until the cylinder bottoms. The main control valve pressure should be 3625 ±50 psi (250 ±4 bar) at full throttle. Repeat for each boom circuit to verify the correct main control valve pressure.

8.5.3 Charge Pressure Checking

Attach a pressure gauge to the test port (3) on the hydrostatic transmission to check the system pressure. The pressure should be 360 +50 psi (25 + 4 bar) with the engine at idle.

Do NOT adjust any relief settings. The unit is preset at the factory and should not be tampered with. If the proper pressure is not read, the unit may be defective.

MY1930

MY2110

If a pressure adjustment is required, adjust the main relief cartridge (2) on the main control valve. Recheck pressure after any adjustment has been made.

8.5.4 Boom Function Pressure Checking

Attach 5000 psi (345 bar) gauge to the test port (1) at the rear of the implement pump to check the system pressure. Make sure the gauge is visible from inside the cab.

See Section 8.5.1, “Pressure Checks and Adjustments,” for start up procedure. Check the boom function pressure with the park brake on and the service brake off at full throttle. Retract each boom circuit function until the cylinder bottoms. Each circuit function pressure should be 3625 ±50 psi (250 ±4 bar) at full throttle.

Note: With the machine at operating temperature, the 3625± 50 psi (250 bar) pressure reading at the main control valve is 125 psi (13,3 bar) HIGHER than the 3500 ± 50 psi (241 bar) of each individual valve section function. DO NOT adjust the main control valve relief pressure below 3625 ± 50 psi (250 bar). To check individual valve section pressures, install a tee and test port between the cylinder being checked and the corresponding valve section on the main control valve.

8.6

G5-18A/2505

8.5.5 Steering Pressure Checking

Attach a pressure gauge to the test fitting (1) at the rear of the implement pump. The pressure reading should be 2700 ±50 psi (186 ±4 bar) with the steering wheel fully turned to one direction.

Note: The 2700 ± 50 psi (186 bar) steering pressure reading at the main control valve is 100 psi (7 bar) HIGHER than the 2600 ± 50 psi (179 bar) steering pressure at the individual valve section. DO NOT adjust the main control valve relief pressure below 3800 ± 50 psi (262 bar). To check individual valve section pressures, install a tee and test port between the cylinder being checked and the corresponding valve section on the main control valve.

Do NOT adjust any relief settings. The unit is preset at the factory and should not be tampered with. If the proper pressure is not read, the unit may be defective.

Hydraulic System

G5-18A/2505

8.7

Hydraulic System

8.6 HYDRAULIC SCHEMATICS

8.6.1 G5-18A

FRONT AXLE

JS2

JS1

AUX TILT

CROWD

P2 P3 P4

235 bar

CROWD

Vg max

Vg min

AUX

AUXILLARY OPTIONS

D U

LIFT TILT

REAR STEERING

CYLINDER

175 bar

FRONT STEERING

CYLINDER

DESCRIPTION

CYLINDER, LIFT

CYLINDER, COMP

CYLINDER, CROWD

VALVE, CHECK (55 PSI)

PUMP, HYDRAULIC (VD)

PUMP, IMPLEMENT

MOTOR, HYDRAULIC

VALVE, STEER SELECT

CYLINDER, TILT

VALVE, PRIORITY

VALVE, STEERING

1314151617181920212224

ITEM #

DESCRIPTION

MAIN CONTROL VALVE, W/AUX.

123456789

ITEM #

IMPLEMENT PUMP SUCTION

DRIVE MOTOR RETURN

PILOT CONTROLLER RETURN

DRIVE PUMP SUCTION

HYDRAULIC RESERVIOR (BUILT IN FRAME)

RADIATOR, COMBINATION W/ HYD. COOLER

AXLE, FRONT (SERVICE BRAKE)

AXLE, FRONT (PARK BRAKE)

VALVE, PILOT SELECT

VALVE, PARK BRAKE RELEASE

VALVE, MASTER CYL. BRAKE

JOYSTICK

101112

VALVE, CHECK (5 PSI)

FILTER, RETURN

VALVE, INCHING

HYDRAULIC RESERVOIR

FILTER RETURN

INCH/STEER VALVE RETURN

FILTER RETURN

8.8

MY2130

G5-18A/2505

8.6.2 2505

Hydraulic System

FRONT AXLE

JS1

JS2

TILT

AUX

CROWD

P2 P3 P4

CROWD

235 bar

Vg max

Vg min

AUX

AUXILIARY OPTIONS

TILT

LIFT

CYLINDER

REAR STEERING

175 bar

CYLINDER

DESCRIPTION

CYLINDER, LIFT16CYLINDER, COMP

CYLINDER, CROWD

CYLINDER, TILT19HYDRAULIC RESERVIOR (BUILT IN FRAME)20RADIATOR, COMBINATION W/ HYD. COOLER

AXLE, FRONT (SERVICE BRAKE)22AXLE, FRONT (PARK BRAKE)24VALVE, BLOCKING25VALVE, CHECK (5 PSI)27SENSOR, STEERING PRESSURE

PUMP, IMPLEMENT4MOTOR, HYDRAULIC

VALVE, STEER SELECT

VALVE, PRIORITY7VALVE, PILOT SELECT8VALVE, PARK BRAKE RELEASE

IMPLEMENT PUMP SUCTION

DRIVE MOTOR RETURN

PILOT CONTROLLER RETURN

DRIVE PUMP SUCTION

VALVE, MASTER CYL. BRAKE

ITEM #

DESCRIPTION

FRONT STEERING

MAIN CONTROL VALVE, W/AUX.2PUMP, HYDRAULIC (VD)

ITEM #

VALVE, LMI

JOYSTICK11FILTER, RETURN12VALVE, INCHING13VALVE, STEERING14VALVE, CHECK (55 PSI)

FILTER RETURN

INCH/STEER VALVE RETURN

FILTER RETURN

G5-18A/2505

MY2370

8.9

Hydraulic System

8.6.3 Auxiliary Options

TRAILER BRAKE CONNECTION

SERVICE BRAKE CONNECTION

INCH/STEER VALVE RETURN

FRONT AUX

2ND

1ST

INCLUDES

HYD. HITCH

LIFT

TRAILER BRAKE VALVE

OPTIONAL TRAILER BRAKE

REAR AUX FRONT AUX

TILT AUX

TO STEERING "LS"PORT

INCLUDES

HYD. HITCH

CROWD

TO STEERING "P" PORT

FRONT AUX

2ND

1ST

REAR AUX

OPTIONAL SECOND FRONT AUXILIARY

-ELECTRIC-

8.10

AUX

OPTIONAL REAR

AUXILIARY

ELECTRIC SECOND FRONT AUX

AUX

OPTIONAL REAR AUX/WITH

MY2140

G5-18A/2505

Hydraulic System

8.7 HYDRAULIC RESERVOIR

The hydraulic reservoir and fuel tank are part of the frame. For this reason, neither tank can be removed. For cleaning instructions, see Section 7.6.2, “Fuel/Hydraulic Oil Tank.”

Occasionally, fluid may seep, leak or be more forcefully expelled from the filter head when system pressure exceeds the rating of the filter head or filler cap. If the return filter becomes plugged, return hydraulic oil will bypass the filter when pressure reaches 22 psi (1,5 bar) and return to the reservoir unfiltered.

Carefully examine fluid seepage or leaks from the hydraulic reservoir to determine the exact cause. Clean the reservoir and note where any seepage occurs.

Leaks from a cracked or damaged reservoir require that the reservoir be flushed completely with water and repaired by a certified welder using approved techniques. If these conditions cannot be met, the reservoir must be replaced in its entirety. Contact your local JLG distributor should reservoir welding be required.

8.7.1 Pressurized Hydraulic Oil Fill Cap

The fill cap will allow the hydraulic oil reservoir to pressurize to 2 psi (0,14 bar). Inspect the condition of the cap seal to maintain proper reservoir pressure.

8.7.2 Hydraulic Oil Reservoir Draining

1. Park the machine on a firm, level surface, fully retract the boom, support the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Remove the drain plug at the bottom of the hydraulic oil reservoir.

5. Transfer the used hydraulic oil into a suitable, covered container, and label as "Used Oil". Dispose of used oil at an approved recycling facility. Clean and reinstall the drain plug.

6. Wipe up any spilled hydraulic oil.

8.7.3 Hydraulic Oil Reservoir Filling

1. Be sure the reservoir is clean and free of all debris.

2. Install new hydraulic oil filters.

3. Fill the reservoir with Mobilfluid oil. Refer to Section 2.4, “Fluids, Lubricants and Capacities.”

4. Start the machine. Run engine to normal operating temperature. Operate all hydraulic functions.

424 (ISO Grade 46)

8.8 HYDRAULIC SYSTEM PUMP

8.8.1 Implement Pump Failure Analysis

The implement pump is the “heart” of the hydraulic system, and whenever there is a problem in the system, the pump often is blamed. However, implement pump failure is seldom due to failure of pump components. Pump failure usually indicates another problem in the hydraulic system.

According to pump manufacturer statistics, 90-95 percent of pump failures are due to one or more of the following causes:

• Aeration

•Cavitation

• Contamination

• Excessive Heat

• Over-Pressurization

• Improper Fluid

In the event of pump failure, investigate further to determine the cause of the problem.

8.8.2 Implement Pump Replacement

a. Implement Pump Removal

1. Park the machine on a firm, level surface, fully retract the boom, support the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Drain the hydraulic oil reservoir. Refer to Section

8.7.2, “Hydraulic Oil Reservoir Draining.”

5. Thoroughly clean the pump (1) and surrounding area, including all hoses and fittings before proceeding.

G5-18A/2505

8.11

Hydraulic System

MY2100

6. Label, disconnect and cap all hydraulic hoses attached to the pump, cap all fittings and plug hoses to keep dirt & debris from entering the hydraulic system.

7. Remove the two bolts that hold the pump in place.

b. Implement Pump Disassembly

1. Mark the position of the body and flange to ensure correct reassembly

2. Remove the nuts and washers attaching the flange to the body. If necessary, carefully separate with a soft faced hammer.

3. Remove the retaining circlip and shaft seal from the flange.

4. Pull out the main shaft assembly. Mark the position of the drive gear and balance plate. Remove the drive gear and balance plate.

5. Discard all seals and clean off all sealant from the flange/body interface.

c. Implement Pump Cleaning

Clean all pump components with a suitable cleaner such as trichlorethylene.

d. Implement Pump Inspection

Inspect internal pump components for wear, damage, etc. If inner surfaces of the pump DO NOT display an ultra-smooth, polished finish, or are damaged in any way, replace the damaged part. Often, dirty hydraulic fluid causes failure of internal pump seals and damage to the polished surfaces within the pump and other hydraulic system components.

Inspect the o-ring groove and shaft seal recess in the mounting flange. Be sure they are undamaged and free from burrs.

The pump must be replaced if:

1. The PFE coated bearings in the body and flange are worn through revealing the bronze backing.

2. The gear side faces are scored.

3. There is a noticeable wear groove on the main shaft where the shaft seal lips run.

4. The bronze balance plates are scored.

Note: It is not recommended that damaged gears/ bodies, flanges or balance plates are replaced individually as this will not constitute a good repair.

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

e. Implement Pump Assembly

Note: Before assembly, all parts must be perfectly clean and lubricated with hydraulic fluid. Renew all seals using hydraulic fluid as a lubricant.

1. Fit the shaft seal mounting flange with the garter spring facings into the pump and refit the circlip.

2. Fit the channel seals and back-up rings into grooves on balance plate into bore. Ensure that the seals remain in their groove and that the two small holes in the balance plate are to the low pressure side of the pump.

3. Insert the main shaft and drive gear into their original bores.

4. Replace the second balance plate into its original position. Be sure the small holes are to the low pressure side, fit the channel seal and back-up ring.

5. Fit the o-ring into its groove in the mounting flange and apply a small amount of Loctite

to the lower

front face of the body.

8.12

G5-18A/2505

Hydraulic System

6. Carefully fit the mounting plate in its original position. The drain hole in the rear face must be to the low pressure side, DO NOT DAMAGE THE SEAL ON

THE SHAFT.

7. Fit washers and nuts to studs and torque to 65-70 lb-ft (88-95 Nm).

8. Pour a small amount of clean hydraulic fluid into the inlet port and check that the shaft can be turned without undue force.

f. Implement Pump Installation

1. Position pump in the mounting position.

Note: Use new o-rings where required. Never reuse orings.

2. Use the two Allen head bolts to secure the pump into place. Torque to 70 lb-ft (95 Nm).

3. Uncap and reconnect previously labeled hydraulic hoses to their proper locations.

4. Fill the hydraulic reservoir with clean, filtered hydraulic oil.

5. Prime the pump by filling the case drain port with fresh, filtered hydraulic oil from a clean container before installing the case drain connector and hose.

6. Check all routing of hoses and tubing for sharp bends or interference with any rotating members. All tube and hose clamps must be tight.

7. Start the engine and run at approximately one-third to one-half throttle for about one minute without moving the machine or operating any hydraulic

functions.

8. Inspect for leaks and check all fluid levels.

8.9 FRONT DRIVE MOTOR

For internal service instructions and detailed specifications, contact your local JLG distributor.

MY2120

a. Front Drive Motor Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the

machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Drain the hydraulic reservoir or attach a vacuum adapter fitting to the reservoir fill tube to reduce oil spillage.

5. Label and disconnect all hydraulic hoses attached to the pump, cap all fittings and plug hoses to keep dirt & debris from entering hydraulic system.

6. Support the motor and remove the four bolts attaching the motor to the front axle.

Note: Check for leaks and repair as required before continuing.

9. Close and secure the engine covers.

g. Pump Test

1. Perform a flow meter test on the pump.

2. Check the load sense.

3. Check the system functions.

G5-18A/2505

b. Front Drive Motor Installation

1. Install the motor onto the front axle. Torque the four bolts to 178 lb-ft (241 Nm). Use only new seals.

2. Uncap and reconnect the previously labeled hydraulic hoses to their appropriate locations.

3. Fill the motor with hydraulic fluid through the fill plug (1) before starting the machine.

4. Refill the hydraulic reservoir and inspect for leaks around the machine.

5. Close and secure the engine covers.

8.13

Hydraulic System

8.10 VALVES AND MANIFOLDS

8.10.1 Main Control Valve

The main control valve is mounted on the rear of the machine behind the rear access panel.

The main control valve assembly consists of various working sections with their own valve assemblies, each providing a specific hydraulic function. The section assemblies are the inlet/outlet (1), lift/lower (2), tilt (3), auxiliary (4), extend/retract (5) and end cap (6) sections.

MY2110

FRONT OF MACHINE

a. Main Control Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Remove the rear panel. Allow the hydraulic fluid to cool.

4. Thoroughly clean the main control valve and surrounding area, including all hoses and fittings, before proceeding.

5. Place a suitable container to catch hydraulic fluid drainage beneath the frame.

6. Label, disconnect and cap all the hydraulic hoses attached to the main control valve. Cap all fittings and openings to keep dirt & debris from entering the hydraulic system.

7. Wipe up any hydraulic fluid spillage in, on, near and around the machine and the work area.

8. Remove the four bolts securing the main control valve to the frame bracket.

b. Main Control Valve Disassembly

1. To disassemble the individual sections of the main control valve, remove the nuts from the end of the tie rod. Pull the tie rods out through the sections.

2. Disassemble each section assembly as required.

Some sections include a pre-adjusted relief valve that regulates pressure in a specific circuit.

NOTICE

DO NOT adjust any of the relief valve assemblies!

Tampering with a relief valve will irrevocably alter pressure in the affected circuit, requiring recalibration or a new relief valve.

Disassemble each Valve Section

1. Carefully separate the inlet/outlet section from the lift/ lower section.

2. Remove the o-rings from between the two sections.

3. Carefully separate each remaining section being careful not to lose the load sense shuttle ball.

4. Remove both end caps from each end of the valve sections then remove each control spool.

5. Remove any check valves, compensator valves, anti-cavitation valves or shock valves from each individual valve section if equipped.

6. Keep all parts being removed from individual valve sections tagged and kept together.

c. Main Control Valve Parts Cleaning

Clean all components with a suitable cleaner, such as trichlorethylene, before continuing. Blow dry.

d. Main Control Valve Parts Inspection

Inspect all parts and internal passageways for wear, damage, etc. If inner surfaces of any component DO NOT display an ultra-smooth, polished finish, or are damaged in any way, replace the damaged part. Often, dirty hydraulic fluid causes failure of internal seals, damage to the polished surfaces within the component, and wear of and/or harm to other parts.

e. Main Control Valve Assembly

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

8.14

G5-18A/2505

Hydraulic System

Assemble each Valve Section

1. Reassemble any check valves, compensator valves, anti-cavitation valves or shock valves from individual valve sections if equipped.

2. Install the control spool being careful not to nick or scratch the valve section bore or the control spool.

3. Install the end caps on each end of the valve section.

Assemble the Main Control Valve

1. Place all three tie rods with the washers and nuts through the end main control valve section.

2. Stand the end main control valve section on end.

3. Install proper o-rings and load sense shuttle on the inner face of the end main control valve section. Align the Crowd section over the three tie rods and slide onto the end main control valve section.

4. Using proper o-rings and load sense shuttle, repeat step three for the remaining sections.

5. Install the washers and nuts on the tie rods and torque to 18.5 lb-ft (25 Nm).

f. Main Control Valve Installation

1. Loosely install the four main control valve mounting bolts through bracket on the rear of the machine.

2. Install the main control valve onto the bracket, aligning the bolts with the holes in the end sections of the main control valve. Slide the main control valve into position, and tighten the bolts.

3. Prime the main control valve by filling the inlet openings with fresh, filtered hydraulic oil from a clean container, before attaching the hoses.

4. Use new oiled o-rings as required. Uncap and reattach and secure all hoses, clamps, etc. to the main control valve.

5. Check the routing of all hoses, wiring and tubing for sharp bends or interference with any rotating members, and install tie wraps and/or protective conduit as required. Tighten all tube and hose clamps.

6. Start the engine and run at approximately one-third to one-half throttle for about one minute without moving the machine or operating any hydraulic

functions.

7. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

8. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

9. Install the rear panel.

g. Main Control Valve Test

Conduct a pressure check of the hydraulic system in its entirety. Adjust pressure(s) as required. Refer to Section

8.5.2, “Main Control Valve Pressure Checking.”

8.10.2 Service Brake Valve

The service brake valve is at the base of the steering column support, concealed by the lower dash cover.

The service brakes themselves are part of the front axle. Refer to Section 5, “Axles, Drive Shafts, Wheels and Tires,” for further information.

a. Service Brake Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Remove the necessary dash panels.

5. Label, disconnect and cap the hydraulic hoses connected to the service brake valve. Cap all fittings and openings to keep dirt & debris from entering the brake system.

6. Remove the bolts that mount the service brake valve to the steering column support

MY2160

G5-18A/2505

8.15

Hydraulic System

Note: DO NOT disassemble the service brake valve. The service brake valve is not serviceable and must be replaced in its entirety, if defective.

b. Service Brake Valve Installation

1. Install the service brake valve to the steering column support with the necessary hardware.

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

2. Use new oiled o-rings as required. Uncap and reconnect the previously labeled hydraulic hoses to the appropriate locations.

3. Check the routing of all hoses, and tubing for sharp bends or interference with any rotating members, and install tie wraps and/or protective conduit as required. Tighten all tube and hose clamps

4. Start the engine and run at approximately one-third to one-half throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect the service brake valve and connections for leaks, and check the brake fluid level. Shut the engine OFF.

6. Replace the necessary dash panels.

7. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

8. Close and secure the engine covers.

Note: The service brake valve circuit will need to be bled after installation. Refer to Section 8.10.4, “Brake Te st.”

8.10.3 Parking Brake Valve

The park brake valve is located in the cab, below the seat.

MY2150

a. Park Brake Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the

machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Remove the four capscrews holding the cover below the seat. The park brake valve is mounted on the backside of the cover.

5. Label, disconnect and cap the hydraulic hoses on each side and bottom of the park brake valve. Disconnect and cap all hoses, fittings, etc.

6. Remove the two capscrews, and two lockwashers mounting the park brake valve to the cover.

Note: DO NOT disassemble the park brake valve. The park brake valve is not serviceable and must be replaced in its entirety, if defective.

8.16

b. Park Brake Valve Installation

1. Install the park brake valve with the two lockwashers and two capscrews to the cover.

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

2. Use new oiled o-rings as required. Uncap, reattach and secure the three hoses.

3. Check the routing of all hoses for sharp bends or interference with any rotating members, and install

tie wraps and/or protective conduit as required.

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Hydraulic System

4. Start the engine and run at approximately one-third to one-half throttle for about one minute, without moving the machine or operating any hydraulic

functions.

5. Inspect the park brake valve and connections for leaks, and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

6. Install the park brake/cover with the four capscrews.

7. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

8. Close and secure the engine covers.

Note: The park brake valve circuit will need to be bled after installation. Refer to Section 8.10.4, “Brake Test.”

8.10.4 Brake Test

Carefully bleed the brake lines as soon as the brake valve is installed on the machine. Air in the system will not allow the brakes to apply properly. There are two brake bleeder locations (1) on the front axle. The outside bleeder is used for the park brake circuit. The inside bleeder is used for the service brake circuit. Work with an assistant to perform this procedure.

1. Place the transmission control lever in (N) NEUTRAL, engage the park brake, and start the engine.Raise the boom to access the brake bleeders. Support boom and turn off engine.

3. DO NOT open the brake bleeder without holding the tubing firmly on the bleeder. There is pressure at the brakes. Carefully open the bleeder with a 12 mm wrench. Have an assistant depress the brake pedal. Close the brake bleeder when air bubbles no longer appear in the oil. Release the brake pedal. Remove the tubing from the brake bleeder.

4. Repeat steps 2 and 3 for the remaining brake bleeder.

5. If bleeding the service brake circuit, install a vacuum pump on the brake reservoir and remove the remainder of the trapped air from the brake system.

6. Check brake fluid level and add fluid if necessary. Refer to Section 2.4, “Fluids, Lubricants and Capacities.”

7. Conduct a pressure and function check of the brake.

8.10.5 Steering Orbitrol Valve

Refer to Section 4.3.2, “Steering Column/Valve Replacement,” for details.

8.10.6 Pilot Select Valve

The pilot select valve is attached to a manifold mounted on a mounting plate inside the frame in front of the comp cylinder.

Verify the correct operation of the pilot select valve solenoids before considering replacement of the valve. The housing of the pilot select valve is not serviceable and must be replaced if defective.

MY2050

2. Remove the plastic cap from the brake bleeder. Attach one end of a length of transparent tubing over the brake bleeder. Place the other end of this tubing in a suitable transparent container that is partially filled with hydraulic oil. The end of the tubing must be below the oil level in the container.

G5-18A/2505

a. Pilot Select Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

4. Label or otherwise mark the hydraulic hoses in relation to the pilot select valve. Disconnect and cap all hoses, fittings, solenoid wire terminal leads, etc.

5. Remove the capscrews that attach the valve to the frame.

6. Remove the pilot select valve from the machine. Wipe up any hydraulic fluid spillage in, on, near and around the machine.

8.17

Hydraulic System

b. Pilot Select Valve Disassembly, Cleaning,

Inspection and Assembly

1. Place the pilot select assembly on a suitable work surface.

2. Remove the solenoid valves and cartridges from the steer select housing.

3. Clean all components with a suitable cleaner before inspection.

4. Inspect the solenoid cartridges for proper operation. Check by shifting the spool to ensure that it is functioning properly. Check that the spring is intact. Inspect the cartridge interior for contamination.

5. Inspect internal passageways of the steer select manifold and valve for wear, damage, etc. If inner surfaces of the manifold DO NOT display an ultrasmooth, polished finish, or components are damaged in any way, replace the manifold or appropriate part. Often, dirty hydraulic fluid causes failure of internal seals and damage to the polished surfaces within the unit

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

6. Install the solenoid valves and cartridges in the pilot select housing.

c. Pilot Select Valve Installation

1. Attach the pilot select manifold valve to the mounting plate on the frame using the socket head capscrews.

2. Connect the hydraulic hoses, fittings, solenoid wire terminal leads, etc., to the pilot select valve.

3. Check the routing of all hoses, wiring and tubing for sharp bends or interference with any rotating members, and install tie wraps and/or protective conduit as required. Tighten all tube and hose clamps.

MY2170

4. Start the engine and run at approximately 1/3-1/2 throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

Note: Check for leaks and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

6. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

7. Close and secure the engine cover.

d. Joystick Test

1. Conduct a function test of the joystick. Refer to Section 8.6, “Hydraulic Schematics,” or Section 9.4, “Electrical System Schematics,” for details.

2. Check boom lift/lower (2), auxiliary (3) and tilt (4) for proper function.

8.10.7 Inching Valve

The inching valve is attached at the front of the frame directly above the steer select valve.

Verify the correct operation of the inching valve solenoid before considering replacement of the valve. The housing of the inching valve is not serviceable and must be replaced if defective.

8.18

a. Inching Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

G5-18A/2505

3. Open the engine covers. Allow the system fluids to cool.

4. Label or otherwise mark the hydraulic hoses in relation to the inching valve. Disconnect and cap all hoses, fittings, solenoid wire terminal leads, etc.

5. Remove the capscrews that attach the valve to the frame.

6. Remove the inching valve from the machine. Wipe up any hydraulic fluid spillage in, on, near and around the machine.

Hydraulic System

MY2330

b. Inching Valve Disassembly, Cleaning, Inspection

and Assembly

1. Place the inching valve assembly on a suitable work surface.

2. Remove the solenoid valve and cartridge from the inching valve housing.

3. Clean all components with a suitable cleaner before inspection.

4. Inspect the solenoid cartridge for proper operation. Check by shifting the spool to ensure that it is functioning properly. Check that the spring is intact. Inspect the cartridge interior for contamination.

5. Inspect internal passageways of the inching valve for wear, damage, etc. If inner surfaces of the manifold DO NOT display an ultra-smooth, polished finish, or components are damaged in any way, replace the manifold or appropriate part. Often, dirty hydraulic fluid causes failure of internal seals and damage to the polished surfaces within the unit

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

6. Install the solenoid valve and cartridge in the inching valve housing.

c. Inching Valve Installation

1. Attach the inching valve to the mounting plate on the frame using the socket head capscrews.

2. Connect the hydraulic hoses, fittings, solenoid wire terminal leads, etc., to the inching valve.

4. Start the engine and run at approximately 1/3-1/2 throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

Note: Check for leaks and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

6. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

7. Close and secure the engine covers.

d. Inching Test

1. Conduct a pressure check of the inching hydraulic circuit. Refer to Section 8.5, “Hydraulic Pressure Diagnosis.”

2. Check inching brake for proper function.

8.10.8 Steer Select Valve

The steer select valve is attached to inside the frame near the front drive motor.

Verify the correct operation of the steer select valve solenoids before considering replacement of the valve. The housing of the steer select valve is not serviceable and must be replaced if defective.

a. Steer Select Manifold and Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine cover. Allow the system fluids to cool.

G5-18A/2505

8.19

Hydraulic System

4. Label or otherwise mark the hydraulic hoses in relation to the steer select manifold. Disconnect and cap all hoses, fittings, solenoid wire terminal leads, etc.

5. Remove the capscrews that attach the manifold to the frame.

6. Remove the steer select manifold with attached steer select valve from the machine. Wipe up any hydraulic fluid spillage in, on, near and around the machine.

b. Steer Select Valve and Manifold Disassembly,

Cleaning, Inspection and Assembly

1. Place the steer select assembly on a suitable work surface.

2. Separate the steer select valve from the manifold by removing the capscrews. Discard the old o-rings.

3. Remove the solenoid valves and cartridges from the steer select housing.

4. Clean all components with a suitable cleaner before inspection.

5. Inspect the solenoid cartridges for proper operation. Check by shifting the spool to ensure that it is functioning properly. Check that the spring is intact. Inspect the cartridge interior for contamination.

6. Inspect internal passageways of the steer select manifold and valve for wear, damage, etc. If inner surfaces of the manifold DO NOT display an ultrasmooth, polished finish, or components are damaged in any way, replace the manifold or appropriate part. Often, dirty hydraulic fluid causes failure of internal seals and damage to the polished surfaces within the unit

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

7. Install the solenoid valves and cartridges in the steer select housing.

8. Attach the steer select valve to the manifold using new, oiled o-rings and socket head capscrews.

c. Steer Select Manifold and Valve Installation

1. Attach the steer select manifold and valve to the mounting plate on the frame using the socket head capscrews.

2. Connect the hydraulic hoses, fittings, solenoid wire terminal leads, etc., to the steer select valve and manifold.

MY2180

4. Start the engine and run at approximately 1/3-1/2 throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

Note: Check for leaks and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

6. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

7. Close and secure the engine cover.

d. Steering Test

1. Conduct a pressure check of the steering hydraulic circuit at the test port on the implement pump. Refer to Section 8.5.5, “Steering Pressure Checking.”

2. Check each steering mode for proper function.

8.20

G5-18A/2505

Hydraulic System

8.10.9 Joystick Enable Valve (CE)

The joystick enable valve is located on top of the frame at the left rear corner of the hydraulic reservoir.

Verify the correct operation of the joystick enable valve solenoid before considering replacement of the valve. The housing of the joystick enable valve is not serviceable and must be replaced if defective.

a. Joystick Enable Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Label or otherwise mark the hydraulic hoses in relation to the joystick enable valve. Disconnect and cap all hoses, fittings, solenoid wire terminal leads, etc.

5. Remove the capscrews that attach the valve to the frame.

6. Remove the joystick enable valve from the machine. Wipe up any hydraulic fluid spillage in, on, near and around the machine.

b. Joystick Enable Valve Disassembly, Cleaning,

Inspection and Assembly

1. Place the joystick enable valve assembly on a suitable work surface.

2. Remove the solenoid valve and cartridge from the joystick enable valve housing.

3. Clean all components with a suitable cleaner before inspection.

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

6. Install the solenoid valve and cartridge in the inching valve housing.

c. Joystick Enable Valve Installation

1. Attach the joystick enable valve to the mounting plate on the frame using the socket head capscrews.

2. Connect the hydraulic hoses, fittings, solenoid wire terminal leads, etc., to the inching valve.

MY2380

4. Start the engine and run at approximately 1/3-1/2 throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

Note: Check for leaks and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

6. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

7. Close and secure the engine covers.

d. LSI Test

1. Conduct a pressure check of the hydraulic circuit. Refer to Section 8.5, “Hydraulic Pressure Diagnosis.”

2. Check joystick enable valve for proper function.

G5-18A/2505

8.21

Hydraulic System

8.10.10 Load Stability Indicator Valve (CE)

The load stability indicator valve is located at the rear of the machine on the left inside frame rail directly below the boom/boom pivot pin.

Verify the correct operation of the LSI valve solenoid before considering replacement of the valve. The housing of the LSI valve is not serviceable and must be replaced if defective.

a. LSI Valve Removal

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

3. Open the engine covers. Allow the system fluids to cool.

4. Label or otherwise mark the hydraulic hoses in relation to the LSI valve. Disconnect and cap all hoses, fittings, solenoid wire terminal leads, etc.

5. Remove the capscrews that attach the valve to the frame.

6. Remove the LSI valve from the machine. Wipe up any hydraulic fluid spillage in, on, near and around the machine.

Note: ALWAYS replace seals, o-rings, gaskets, etc., with new parts to help ensure proper sealing and operation. Lubricate seals and o-rings with clean hydraulic oil.

6. Install the solenoid valve and cartridge in the inching valve housing.

c. LSI Valve Installation

1. Attach the LSI valve to the mounting plate on the frame using the socket head capscrews.

2. Connect the hydraulic hoses, fittings, solenoid wire terminal leads, etc., to the inching valve.

MY2590

b. LSI Valve Disassembly, Cleaning, Inspection and

Assembly

1. Place the LSI valve assembly on a suitable work surface.

2. Remove the solenoid valve and cartridge from the LSI valve housing.

3. Clean all components with a suitable cleaner before inspection.

8.22

4. Start the engine and run at approximately 1/3-1/2 throttle for about one minute, without moving the machine or operating any hydraulic functions.

5. Inspect for leaks and check the level of the hydraulic fluid in the reservoir. Shut the engine OFF.

Note: Check for leaks and repair as required before continuing. Add hydraulic fluid to the reservoir as needed.

6. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

7. Close and secure the engine covers.

d. LSI Valve Test

1. Conduct a pressure check of the hydraulic circuit. Refer to Section 8.5, “Hydraulic Pressure Diagnosis.”

2. Check LSI valve for proper function.

G5-18A/2505

Hydraulic System

8.11 HYDRAULIC CYLINDERS

8.11.1 General Cylinder Removal Instructions

1. Park the machine on a firm, level surface, fully retract the boom, lower the boom, place the transmission control lever in (N) NEUTRAL, engage the park brake and shut the engine OFF.

2. Chock the wheels.

3. Place an Do Not Operate Tag on both the ignition key switch and the steering wheel, stating that the machine should not be operated.

4. Open the engine cover. Allow the system fluids to cool.

5. Label, disconnect and cap hydraulic hoses in relation to the cylinder.

6. Attach a suitable sling to an appropriate lifting device and to the cylinder. Make sure the device used can actually support the cylinder.

7. Remove the lock bolt and/or any retaining clips securing the cylinder pins. Remove the cylinder pins.

8. Remove the cylinder.

9. Wipe up any hydraulic fluid spillage in, on, near or around the machine.

8.11.2 General Cylinder Disassembly

1. Clean the cylinder with a suitable cleaner before disassembly. Remove all dirt, debris and grease from the cylinder.

2. Clamp the barrel end of the cylinder in a soft-jawed vise or other acceptable holding equipment if

possible.

MAH0160

NOTICE

DO NOT tamper with or attempt to adjust the counterbalance valve cartridge. If adjustment is necessary, replace the counterbalance valve with a new part.

4. Extend the rod (5) to allow access to the base of the cylinder.

NOTICE

Avoid using excessive force when clamping the cylinder in a vise. Apply only enough force to hold the cylinder securely. Excessive force can damage the cylinder tube.

3. If applicable, remove the counterbalance valve from the side of the cylinder barrel.

G5-18A/2505

Protect the finish on the rod at all times. Damage to the surface of the rod can cause seal failure.

5. Using a pin spanner wrench, unscrew the head gland (6) from the barrel (1). A considerable amount of force will be necessary to remove the head gland. Carefully slide the head gland down along the rod toward the rod eye end, away from the cylinder barrel.

8.23

Hydraulic System

NOTICE

When sliding the rod and piston assembly out of the tube, prevent the threaded end of the tube from damaging the piston. Keep the rod centered within the tube to help prevent binding.

6. Carefully pull the rod assembly along with the head gland out of the cylinder barrel.

7. Fasten the rod end in a soft-jawed vise, and put a padded support under and near the threaded end of the rod to help prevent damage to the rod.

8. Remove the set screw (3) from the piston (4).

Note: It may be necessary to apply heat to break the bond of the sealant between the piston and the rod before the piston can be removed.

Some cylinder parts are sealed with a special organic sealant and locking compound. Before attempting to disassemble these parts, remove any accessible seals from the area of the bonded parts. Wipe off any hydraulic oil, then heat the part(s) uniformly to break the bond. A temperature of 300-400° F (149-204° C) will destroy the bond. Avoid overheating, or the parts may become distorted or damaged. Apply sufficient torque for removal while the parts are still hot. The sealant often leaves a white, powdery residue on threads and other parts, which must be removed by brushing with a soft brass wire brush prior to reassembly.

9. Remove the piston head (4) from the rod (5) and carefully slide the head gland (6) off the end of the rod.

10. Remove all seals, back-up rings and o-rings (2) from the piston head and all seals, back-up rings and orings from the head gland.

2. Clean all metal parts with an approved cleaning solvent such as trichlorethylene. Carefully clean cavities, grooves, threads, etc.

Note: If a white powdery residue is present on threads and parts, it can be removed. Clean the residue away with a soft brass wire brush prior to reassembly, and wipe with loctite

cleaner before reinstallation.

8.11.4 Cylinder Inspection

1. Inspect internal surfaces and all parts for wear, damage, etc. If the inner surface of the tube does not display a smooth finish, or is scored or damaged in any way, replace the tube.

2. Remove light scratches on the piston, rod or inner surface of the tube with a 400-600 grit emery cloth. Use the emery cloth in a rotary motion to polish out and blend the scratch(es) into the surrounding surface.

3. Check the piston rod assembly for run-out. If the rod is bent, it must be replaced.

8.11.5 General Cylinder Assembly

1. Use the proper tools for specific installation tasks. Clean tools are required for assembly.

2. Install new seals, back-up rings and o-rings (2) on the piston (4) and the head gland (6).

Note: The Crowd cylinder has a spacer that MUST be installed over the rod AFTER the head gland and BEFORE the piston head.

3. Fasten the rod eye in a soft-jawed vise, and place a padded support under and near the threaded end of

the rod (5) to prevent any damage to the rod.

NOTICE

Note: The head gland bearing will need to be inspected

to determine if replacement is necessary.

DO NOT attempt to salvage cylinder seals, sealing rings or o-rings. ALWAYS use a new, complete seal kit when rebuilding hydraulic components. Consult the parts manual for ordering information.

8.11.3 Cylinder Cleaning Instructions

1. Discard all seals, back-up rings and o-rings. Replace with new items from complete seal kits to help ensure proper cylinder function.

8.24

Protect the finish on the rod at all times. Damage to the surface of the rod can cause seal failure.

4. Lubricate and slide the head gland (6) over the cylinder rod (5). Install the piston head (4) on to the end of the cylinder rod. Loctite setscrew (3) in the piston head. Refer to Section

8.11.8, “Hydraulic Cylinder Torque Specifications,” for tightening guidelines for the piston head and the set screw.

and install the

G5-18A/2505

NOTICE

Avoid using excessive force when clamping the cylinder barrel in a vise. Apply only enough force to hold the cylinder barrel securely. Excessive force can damage the cylinder barrel.

5. Place the cylinder barrel (1) in a soft-jawed vise or other acceptable holding equipment if possible.

NOTICE

When sliding the rod and piston assembly into the cylinder barrel, prevent the threaded end of the cylinder barrel from damaging the piston head. Keep the cylinder rod centered within the barrel to prevent binding.

6. Carefully insert the cylinder rod assembly into the tube.

7. Screw the head gland (6) into the cylinder barrel (1) and tighten with a spanner wrench. Refer to Section

8.11.8, “Hydraulic Cylinder Torque Specifications,” for tightening guidelines for the head gland.

8. If applicable, thread the new counterbalance valve into the block on the cylinder barrel.

Hydraulic System

8.11.6 General Cylinder Installation

1. Grease the bushings at the ends of the hydraulic cylinder. Using an appropriate sling, lift the cylinder into it’s mounting position.

2. Align cylinder bushing and install pin, lock bolt or retaining clip.

3. Uncap and connect the hydraulic hoses in relation to the labels or markings made during removal.

4. Before starting the machine, check fluid level of the hydraulic fluid reservoir and if necessary, fill to full mark with Mobilfluid® 424 (ISO Grade 46) Tractor Fluid.

5. Start the machine and run at low idle for about one minute. Slowly activate hydraulic cylinder function in both directions allowing cylinder to fill with hydraulic oil.

6. Inspect for leaks and check level of hydraulic fluid in reservoir. Add hydraulic fluid if needed.

7. If no leaks are present, operate the hydraulic function at least twenty times at full throttle to bleed any air from the cylinder and hoses.

Note: To bleed air from the tilt cylinder, operate the tilt function along with the lift cylinder as described above. More operation cycles may be required to clear all air from the system.

8. Wipe up any hydraulic fluid spillage in, on, near and around the machine, work area and tools.

9. Close and secure the engine covers.

8.11.7 Steering Cylinders

The steering cylinders are attached to each axle center housing. The steer cylinders are covered in the appropriate Dana axle literature.

MAH0160

G5-18A/2505

8.25

Hydraulic System

8.11.8 Hydraulic Cylinder Torque Specifications

Description

Extend/Retract Cylinder Set Screw 60-69 lb-ft (81-94 Nm)

All Other Cylinder Set Screws 16-18 lb-ft (22-25 Nm)

Counter Balance Valves 45-50 lb-ft (61-68 Nm)

Lift/Lower Cylinder

Head Gland 300-400 lb-ft (406-542 Nm)

Piston 1800-2000 lb-ft (2440-2712 Nm)

Extend/Retract Cylinder

Head Gland 200-250 lb-ft (271-339 Nm)

Piston 200-240 lb-ft (271-325 Nm)

Tilt Cylinder

Head Gland 300-400 lb-ft (406-542 Nm)

Piston 1400-1500 lb-ft (1898-2034 Nm)

Compensating Cylinder

Head Gland 300-400 lb-ft (406-542 Nm)

Piston 1400-1500 lb-ft (1898-2034 Nm)

Use Loctite

271 or Equivalent on all Piston Applications

243 or Equivalent on all Set Screws

8.26

G5-18A/2505

JLG G5-18A Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

1.1 INTRODUCTION

1.2 DISCLAIMER

1.3 OPERATION & SAFETY MANUAL

1.4 DO NOT OPERATE TAGS

1.5 SAFETY INFORMATION

1.5.1 Safety Alert System and Signal Words

1.6 SAFETY INSTRUCTIONS

1.6.1 Personal Hazards

1.6.2 Equipment Hazards

1.6.3 General Hazards

1.6.4 Operational Hazards

1.7 SAFETY DECALS

2.1 REPLACEMENT PARTS AND WARRANTY INFORMATION

2.2 TORQUES

2.2.1 ASTM Fastener Torque Chart (English)

2.2.2 ASTM Fastener Torque Chart (Metric)

2.2.3 Metric Fastener Torque Chart

2.3 SPECIFICATIONS

2.3.1 Travel Speed

2.3.2 Hydraulic Cylinder Performance Specifications

2.3.3 Electrical System

2.3.4 Engine Performance Specifications

2.3.5 Tires

2.4 FLUIDS, LUBRICANTS AND CAPACITIES

2.5 MAINTENANCE SCHEDULES

2.5.1 10,1st 50 & 50 Hour Maintenance Schedule

2.5.2 1st 250, 250, 500 & 1000 Hour Maintenance Schedule

2.6 LUBRICATION SCHEDULE

2.6.1 250 Hour Lubrication Schedule

3.1 BOOM SYSTEM COMPONENT TERMINOLOGY

3.2 BOOM SYSTEM - TWO SECTION BOOM

3.2.1 Boom System Description

3.3 BOOM ASSEMBLY MAINTENANCE

3.3.1 Second Section Boom Removal

3.3.2 First Boom Section Removal

3.3.3 First Boom Section Installation

3.3.4 Second Boom Section Installation

3.3.5 Complete Boom Removal

3.3.6 Second Section Boom Removal

3.3.7 Second Section Boom Installation

3.3.8 Boom Installation

3.3.9 Extend/Retract Cylinder Removal

3.3.10 Extend/Retract Cylinder Installation

3.4 BOOM WEAR PADS

3.4.1 Wear Pad Inspection

3.4.2 Boom Wear Pad Replacement

3.4.3 Boom Wear Pad Lubrication

3.5 QUICK ATTACH ASSEMBLY

3.5.1 Connecting with a Mechanical JLG Quick Attach

3.5.2 Connecting with a Hydraulic JLG Quick Attach

3.5.3 Connecting with a Universal Quick Attach

3.5.4 Connecting a Hydraulic Operated Attachment

3.5.5 Quick Attach Removal

3.5.6 Quick Attach Installation

3.6 TROUBLESHOOTING

4.1 OPERATOR’S CAB AND COVERS COMPONENT TERMINOLOGY

4.2 OPERATOR’S CAB

4.2.1 Operator’s Cab Description

4.3 CAB COMPONENTS

4.3.1 Steering Wheel

4.2.2 Serial Number Decal

4.3.2 Steering Column/Valve Replacement

4.3.3 Brake Pedal and Valve

4.3.4 Throttle Pedal Replacement

4.3.5 Joystick Assembly Replacement

4.3.6 Windshield Wiper Assembly

4.3.7 Windshield Washer Assembly

4.3.8 Heater/Defroster System

4.4 CAB REMOVAL

4.5 CAB INSTALLATION

5.1 AXLE, DRIVE SHAFT AND WHEEL COMPONENT TERMINOLOGY

5.2 GENERAL INFORMATION

5.3 AXLE ASSEMBLIES

5.3.1 Axle Serial Number Plate

5.3.2 Axle Specifications

5.3.3 Axle Internal Service