JLG G12-55A Service Manual

Service Manual

Models

G10-55A

G12-55A

AccuPlace

31200452

Original

January 20, 2009

An Oshkosh Corporation Company

EFFECTIVITY PAGE

January 20, 2009 - A - Original Issue Of Manual

31200452 G10-55A & G12-55A AccuPlace i

EFFECTIVITY PAGE

G10-55A & G12-55A AccuPlace 31200452-ii

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 Fluid and Lubricant Capacities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8

2.5 Service and Maintenance Schedules. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

2.6 Lubrication Schedules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.11

Section 3

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

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

3.2 Boom System - Four Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

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

3.4 Boom Extend and Retract Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

3.5 Boom Section Separation Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

3.6 Hydraulic Sub-Assembly Removal/Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

3.7 Boom Wear Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.17

3.8 Quick Switch Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.18

3.9 Forks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.18

3.10 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.19

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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7

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 Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

G10-55A & G12-55A AccuPlace

Section Subject Page

5.7 Towing a Disabled machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.11

Section 6

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

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

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

6.3 Transmission Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

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

6.5 Transmission Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3

6.6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.7

Section 7

Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1

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

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

7.3 Engine Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6

7.4 Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.6

7.5 Engine Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8

7.6 Air Cleaner Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.7 Engine Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.9

7.8 Torque Convertor Diaphragm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.11

7.9 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7.12

Section 8

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

8.1 Hydraulic Component Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2

8.2 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3

8.3 Hydraulic Pressure Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4

8.4 Hydraulic Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8.5

8.5 Hydraulic System Schematics and Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.7

8.6 Hydraulic Reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.12

8.7 Engine Implement Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.13

8.8 Control Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8.14

8.9 Hydraulic Piston Accumulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.22

8.10 Hydraulic Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.24

Section 9

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

9.1 Electrical Component Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3

9.2 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.4

9.3 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.4

9.4 Fuses and Relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.4

9.5 Control Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.7

9.6 Electrical System Schematics And Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.15

9.7 Engine Start Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.23

9.8 Charging Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9.24

9.9 Window Wiper/Washer Windshield Wiper Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.25

9.10 Cab Heater and Fan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.26

9.11 Solenoids, Senders and Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.27

9.12 Display Monitor and Gauges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.35

9.13 Dash Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9.36

9.14 Engine Indicator Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.38

9.15 Hand Held Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.39

G10-55A & G12-55A AccuPlace

Section 1

Safety Practices

Contents

PARAGRAPH TITLE PAGE

1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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

G10-55A & G12-55A AccuPlace

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 manual holder located 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

G10-55A & G12-55A AccuPlace

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.

G10-55A & G12-55A AccuPlace

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: 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.

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

G10-55A & G12-55A AccuPlace

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 Speeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.2 Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.3 Engine Performance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6

2.3.4 Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7

2.4 Fluid and Lubricant Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8

2.5 Service and Maintenance Schedules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

2.5.1 10, 1st 100 & 50 Hour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9

2.5.2 250, 500, 1000 & 1500 Hour. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.10

2.6 Lubrication Schedules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.11

G10-55A & G12-55A AccuPlace

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 (1) is located as indicated in the figure.

MY1000

Note: The replacement of any part on this machine with any other than JLG authorized replacement parts 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

G10-55A & G12-55A AccuPlace

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

GRADE 2 NUTS

SAE GRADE 5 BOLTS &

DRY OR

CLAMP

TENSILE

BOLT

THDS.

263

LOCTITE

LOAD

AREA

STRESS

DIA.

PER

INCH

SIZE

G10-55A & G12-55A AccuPlace

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

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

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

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

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

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

1.3750

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

1-3/8

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

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

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

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

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

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

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

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

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

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

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

0.3125

0.3750

0.4375

0.5000

0.5625

0.6250

0.7500

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

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

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

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

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

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

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

5/16

3/8

7/16

1/2

9/16

5/8

3/4

0.8750

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

7/8

1.0000

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

1.1250

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

1-1/8

1.2500

1-1/4

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

0.00604 380 .8 .8 — — 540 1.4 1.0 — — — — —

0.00909 580 1.8 1.4 — — 820 2.6 2.0 — — — — —

0.01400 900 3.4 2.4 — — 1260 4.6 3.4 — — — — —

40 0.01015 610 2.0 1.6 — — 920 2.8 2.2 — — — — —832

0.1640

36 0.01474 940 3.4 2.6 — — 1320 5 3.6 — — — — —1024

0.01750 1120 5 3.6 — — 1580 7 5 — — — — —

0.1900

32 0.02000 1285 6 4 — — 1800 8 6 — — — — —

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

THDS.

SIZE

0.1120

0.1380

48 0.00661 420 1.0 .8 — — 600 1.5 1.0 — — — — —632

INCH

0.0318 2020 11 8 — 12 2860 16 12 — 18 3180 18 19

0.2500

28 0.0364 2320 14 10 — 15 3280 19 14 — 21 3640 19 20

1/4

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

0.0524 3340 23 18 22 26 4720 34 24 30 41 5240 34 38

0.3125

24 0.0580 3700 26 19 23 28 5220 34 27 34 41 5800 37 41

5/16

0.0775 4940 41 31 38 47 7000 61 47 54 68 7750 61 68

0.3750

24 0.0878 5600 47 34 43 54 7900 68 47 61 75 8780 68 75

3/8

0.1063 6800 68 47 61 75 9550 95 75 85 108 10630 95 104

0.4375

20 0.1187 7550 75 54 68 81 10700 108 81 95 122 11870 102 111

7/16

0.1419 9050 102 75 92 115 12750 149 108 130 163 14190 149 163

0.5000

20 0.1599 10700 122 88 108 136 14400 163 122 146 183 15990 156 172

1/2

0.1820 11600 149 108 133 163 16400 203 149 188 224 18200 210 230

0.5625

18 0.2030 12950 163 122 148 183 18250 230 176 209 258 20300 224 247

9/16

0.2260 14400 203 149 183 224 20350 298 230 244 325 22600 285 313

0.6250

18 0.2560 16300 230 176 207 258 23000 325 244 277 359 25600 298 328

5/8

0.3340 21300 353 271 325 386 30100 515 380 408 569 33400 495 542

0.7500

16 0.3730 23800 407 298 363 447 33600 569 434 456 630 37300 542 597

3/4

0.4620 29400 583 434 523 644 41600 813 624 658 895 46200 793 874

0.8750

14 0.5090 32400 637 475 576 705 45800 895 678 724 983 50900 861 949

7/8

0.6060 38600 868 651 785 915 51500 1220 922 931 1342 60600 1173 1288

1.0000

12 0.6630 42200 949 719 858 997 59700 1356 1003 1079 1491 66300 1241 1356

0.7630 42300 1085 813 968 1139 68700 1735 1302 1396 1898 76300 1681 1851

1.1250

1-1/8

12 0.8560 47500 1193 895 1087 1254 77000 1952 1464 1566 2135 85600 1871 2061

0.9690 53800 1518 1139 1368 1593 87200 2468 1844 1970 2712 96900 2373 2610

1.2500

1-1/4

12 1.0730 59600 1681 1247 1516 1763 96600 2712 2034 2183 2983 107300 2549 2807

1.1550 64100 1979 1491 1792 2068 104000 3227 2413 2586 3559 115500 3145 3457

1.3750

1-3/8

12 1.3150 73000 2278 1708 2042 2373 118100 3688 2766 2935 4067 131500 3308 3640

1.4050 78000 2630 1979 2379 2745 126500 4284 3200 3430 4711 140500 4122 4535

1.5000

1-1/2

12 1.5800 87700 2983 2224 2676 3118 142200 4827 3606 3856 5322 158000 4433 4881

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

G10-55A & G12-55A AccuPlace

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.

G10-55A & G12-55A AccuPlace

METRIC CLASS 8.8METRIC CLASS 10.

2.5

General Information and Specifications

2.3 SPECIFICATIONS

2.3.1 Travel Speeds

G10-55A G12-55A

First Gear 3.4 mph (5,4 km/h) 3.5 mph (5,6 km/h)

Second Gear 6.1 mph (9,8 km/h) 6.3 mph (10,1 km/h)

Third Gear 13.8 mph (22,2 km/h) 14.1 mph (22,7 km/h)

Fourth Gear 20.0 mph (32,2 km/h) 20.4 mph (32,8 km/h)

2.3.2 Electrical System

Battery:

Type, Rating 12 BCI, Negative (-) Ground, Maintenance Free

Quantity 1

Reserve Capacity 1,000 Cold Cranking Amps @ 0° F (-18° C)

Group/Series Group 31

Alternator 12V, 95 Amps

2.3.3 Engine Performance Specifications

Description G10-55A G12-55A

Engine Make/Model Perkins 1104D - 125HP Perkins 1104D - 142 HP

Displacement 269 in³ (4,4 liters) 269 in³ (4,4 liters)

Low Idle 1000 rpm 900 rpm

High Idle 2,400 to 2,650 rpm 2,400 to 2,650 rpm

Horsepower 125 HP (93 kW) @ 2400 rpm 142 HP (104 kW) @ 2400 rpm

Peak Torque Not Available at Publication 410 lb-ft (556 Nm) @ 1400 rpm

Fuel Delivery Fuel Injection Fuel Injection

Air Cleaner Dry Type, Replaceable Primary and

Safety Elements

Dry Type, Replaceable Primary and

Safety Elements

2.6

G10-55A & G12-55A AccuPlace

General Information and Specifications

2.3.4 Tires

Note: Standard wheel lug nut torque is 350-400 lb-ft (475-542 Nm).

a. G10-55A

Size Tire Type Minimum Ply/

Fill Type Pressure

Star Rating

14.00 x 24 G-2/L-2 Bias Ply Traction 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 720 lb foam

14.00 x 24 G-3/L-3 Bias Ply Rock 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 720 lb foam

14.00 x 24 G-2/L-2 Radial 1 Star Pneumatic 70 psi (4,8 bar)

approx. 720 lb foam

14.00 x 24 Solid N/A Solid Rubber N/A

17.50 x 25 G-2/L-2 Bias Ply Traction 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 785 lb foam

17.50 x 25 G-3/L-3 Bias Ply Rock 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 785 lb foam

17.50 x 25 G-2/L-2 Radial 1 Star Pneumatic 70 psi (4,8 bar)

approx. 785 lb foam

b. G12-55A

Size Tire Type Minimum Ply/

Fill Type Pressure

Star Rating

14.00 x 24 Solid N/A Solid Rubber N/A

17.50 x 25 G-2/L-2 Bias Ply Traction 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 785 lb foam

17.50 x 25 G-3/L-3 Bias Ply Rock 12 Ply Pneumatic 65 psi (4,5 bar)

approx. 785 lb foam

17.50 x 25 G-2/L-2 Radial 1 Star Pneumatic 70 psi (4,8 bar)

approx. 785 lb foam

G10-55A & G12-55A AccuPlace

2.7

General Information and Specifications

2.4 FLUID AND LUBRICANT CAPACITIES

Engine Crankcase Oil

Capacity with Filter Change - Perkins 7 quarts (6,5 liters)

Oil Type 15W-40 CE

Fuel Tank

Capacity 38 gallons (144 liters)

Type of Fuel Low Sulfur Diesel #2

Cooling System

System Capacity - Perkins 20.5 quarts (19,4 liters)

Overflow Bottle Capacity 3 quarts (2,8 liters)

Type of Fluid 50/50 ethylene glycol & water

Coolant Conditioner (refer engine manual) 0.5 quarts (0,47 liters)

Transmission

Capacity with Filter Change 4.23 gallons (16 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Transfer Case

Capacity 1.5 quarts (1,4 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Axles

Differential Housing Capacity Front Axle - 15.8 quarts (15 liters)

Rear Axle - 16.9 quarts (16 liters)

Wheel End Capacity 2 quarts (1,9 liters)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid (ISO 46)

Hydraulic System

System Capacity G10-55A - 63 gallons (238 liters)

G12-55A - 65 gallons (246 liters)

Reservoir Capacity 38 gallons (144 liters)

Auxiliary Hydraulic Circuit Max Flow 16 gpm (72,7 lpm)

Type of Fluid Mobilfluid

424 Tractor Hydraulic Fluid

2.8

G10-55A & G12-55A AccuPlace

2.5 SERVICE AND MAINTENANCE SCHEDULES

2.5.1 10, 1st 100 & 50 Hour

EVERY

General Information and Specifications

Check Fuel

Level

Check

Transmission

Oil Level

100

Change Axle Oil

(

Check Wheel

Lug Nut

Torque

)

Check Tire

Pressure

Check Hydraulic

Return Filter

Indicator

Change Wheel

End Oil

Check Boom

Chain Tension

Air Filter

Restriction

Indicator

Check Auto-

Sway Function

Change Engine

Oil & Filter

Check Engine

Oil Level

Change

Transmission

Oil & Filter

Check Hydraulic

Oil Level

Change

Transfer

Case Oil

G10-55A & G12-55A AccuPlace

Drain Fuel/

Water

Separator

EVERY

Check Engine Coolant Level

Check

Battery

Lubrication

Schedule

MY1731

2.9

General Information and Specifications

2.5.2 250, 500, 1000 & 1500 Hour

EVERY

250

Change Engine

Oil and

Filter*

Check Boom

Chain

Tension

Change Fuel

Filter

Check Axle

Oil Level

Check Boom

Bearing

Pads

(

Check Wheel

Lug Nut

Torque

)

Check Wheel

End Oil Levels

Check Transfer

Case Oil Level

EVERY

500

EVERY

1000

Air Filter

Vacuator

Valve

Check Rear Axle

Stabilization (if equipped)

Check

Fan Belt

Change

Transmission

Oil & Filter

Change

Transfer Case

Oil

Change Axle Oil

Change Wheel

End Oil

EVERY

1500

Change

Engine Coolant

Note: Engine oil & filter service interval can be extended. See Engine Manual for details.

2.10

Change

Hydraulic

Fluid & Filters

Change

Hydraulic Tank

Breather

MY0090

G10-55A & G12-55A AccuPlace

2.6 LUBRICATION SCHEDULES

a. 50 Hour

EVERY

General Information and Specifications

G10-55A & G12-55A AccuPlace

OY1630

2.11

General Information and Specifications

b. 250 Hour

EVERY

250

2.12

OW1210

G10-55A & G12-55A AccuPlace

Section 3

Boom

Contents

PARAGRAPH TITLE PAGE

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

3.2 Boom System - Four Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.2.1 Boom System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

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

3.3.1 Boom Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3

3.3.2 Second, Third & Fourth Boom Section Removal . . . . . . . . . . . . . . . . . . . 3.4

3.3.3 Third & Fourth Boom Section Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4

3.3.4 Fourth Boom Section Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

3.3.5 Fourth Boom Section Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5

3.3.6 Third & Fourth Boom Section Installation . . . . . . . . . . . . . . . . . . . . . . . . . 3.6

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

3.3.8 Boom Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.8

3.4 Boom Extend and Retract Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

3.4.1 Boom Chain Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

3.4.2 Inspection Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9

3.4.3 Expose Chains for Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11

3.4.4 Chain Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12

3.4.5 Retract Chain Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12

3.4.6 Retract Chain Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13

3.4.7 Extend Chain Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13

3.4.8 Extend Chain Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13

3.5 Boom Section Separation Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

3.6 Hydraulic Sub-Assembly Removal/Installation . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

3.6.1 Hydraulic Sub-Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14

3.6.2 Assembling the Hydraulic Sub-Assembly . . . . . . . . . . . . . . . . . . . . . . . . . 3.16

3.6.3 Hydraulic Sub-Assembly Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.16

3.7 Boom Wear Pads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.17

3.7.1 Wear Pad Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.17

3.7.2 Boom Wear Pad Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.17

3.7.3 Boom Wear Pad Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.17

3.8 Quick Switch Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.18

3.8.1 Quick Switch Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.18

3.8.2 Quick Switch Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.18

3.9 Forks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.18

3.10 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.19

G10-55A & G12-55A AccuPlace

3.1

Boom

3.1 BOOM SYSTEM COMPONENT TERMINOLOGY

The following illustrations identify the components that are referred to throughout this section.

EXTEND

CHAINS

FOURTH BOOM

SECTION

ELECTRICAL

CONNECTION

THIRD BOOM

SECTION

SECOND BOOM

SECTION

FIRST

BOOM

SECTION

ATTACHMENT

QUICK SWITCH

ATTACHMENT

TILT CYLINDER

BOOM HYDRAULIC

ASSEMBLY

(Inside Boom)

(Underside Of Boom)

EXTEND/RETRACT

CYLINDER

RETRACT

CHAINS

HOSE

SHEAVES

MAP0500

3.2

G10-55A & G12-55A AccuPlace

Boom

3.2 BOOM SYSTEM - FOUR SECTION

3.2.1 Boom System Operation

The four section boom consists of the first, second, third and fourth assemblies with double third and fourth section extend chains, a double third section retract chain and a single fourth section retract chain.

As the extend/retract cylinder, which is anchored at the front of the second boom section, and the rear of the first boom section begins to extend, it forces the second boom section out of the first boom section.

The boom sections are connected by extend and retract chains. These chains are routed around sheaves on the second and third boom sections. As the second section is forced out hydraulically, the third and fourth boom sections are pulled out by the extend chains.

As hydraulic pressure is applied to the retract port on the extend/retract cylinder, the second boom section is pulled back into the first boom section, and the retract chain pulls the third and fourth boom sections back into the second boom section.

This mechanical linkage formed by the chains and supporting hardware, extends and retracts the third and fourth boom sections at the same rate.

The boom section lifts and lowers via action of the lift/ lower cylinder.

3.3 BOOM ASSEMBLY MAINTENANCE

These instructions must be completed in sequence. The second, third and fourth boom sections are removed from the first boom section. The third and fourth boom sections are removed from the second boom section. The fourth boom section is removed from the third boom section.

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.

3.3.1 Boom Removal

1. Remove any attachment from the quick switch assembly.

Note: If replacing the fourth section boom, remove the quick switch from the fourth section. Refer to Section

3.8.1, “Quick Switch Removal.”

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

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.

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

6. Support the front of the boom by placing a sling behind the boom head.

7. Label, disconnect and cap all hydraulic hoses for the extend/retract and tilt circuits. Cap all fittings and openings to keep dirt & debris from entering the hydraulic system.

8. Support the lift cylinder on the left side of the machine. Remove the lock bolt and rod end pin. Lower the lift cylinder onto the frame rails. Repeat this step for the right side lift cylinder.

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

10. Remove the boom angle sensors from both the left and right side of the boom. Refer to Section 9.11.12, “Boom Angle Sensors.”

11. Remove the bolt securing the boom pivot pin. Pull out the boom pivot pin.

12. Lift the complete boom off machine and set on level ground or supports.

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 can result in death or severe personal injury.

G10-55A & G12-55A AccuPlace

3.3

Boom

3.3.2 Second, Third & Fourth Boom Section Removal

1. Set the complete boom on level ground and by repositioning the slings, turn boom over on to the top side. Set the complete boom on suitable stands to begin tear down.

Note: With the complete boom setting upside down, the removal and replacing of each boom section, hoses, extend and retract chains and hose carrier are made much easier.

2. Remove the extend/retract cylinder support from the front of the boom.

3. Support the extend/retract cylinder with a suitable sling. Remove the lock bolt and pin from both ends of the cylinder. Remove the cylinder.

4. Unhook the latch on the Boom Length Sensor cable from the third boom section. Refer to Section

9.11.13, “Boom Length Sensor.”

5. At the boom head, attach a sling through the rod end of the tilt cylinder. Remove both hoses from the tilt cylinder. Plug the hose ends and cap the tilt cylinder fittings to prevent dirt and debris from entering the hydraulic system. Remove the pin from the barrel end of the tilt cylinder and remove the cylinder from the boom head.

6. Loosen and remove the bottom rear wear pads and rear side bearing pads from the second boom section. Tag each pad, backing plate, shim and bolts from each location.

7. Release tension from the hoses on the hose take-up weldment (1).

hose ends and tube ends to prevent dirt and debris from entering the hydraulic system.

9. Disconnect the top front chains (3) from the chain clevis on the first and second boom section.

10. Release the chain tension from the front top chains.

11. Remove the front top chain rollers from the second and third boom sections.

12. Remove the chain adjustment block (4) from the first boom section.

13. Remove all wear pads from the front of the first boom section. Tag each pad, backing plate, shim and bolts from each location.

14. Carefully pull the second, third and fourth boom sections together from the first boom section and place on suitable support for further separation.

3.3.3 Third & Fourth Boom Section Removal

1. Loosen and remove the bottom rear and side wear pads from the third boom section. Tag each pad, backing plate, shim and bolts from each location.

2. Remove the standard and optional hose sheaves from the rear of the second boom section.

3. Remove the chain and chain clevis (5) from the rear of the second boom section.

MAP0660

8. Loosen the hydraulic hoses (2) and electrical cables if equipped on the hose take-up weldment. Plug the

3.4

MAP0670

4. Remove the hydraulic sub-assembly bracket (6) and hardware from the rear of the third boom section.

5. Pull the hydraulic sub-assembly partially out through the rear of the boom to access the hoses.

6. Loosen and remove the hoses from the rear of the hydraulic sub-assembly.

7. Release the tension on the clevis before proceeding.

8. Loosen and remove the chain adjustment block from the bottom of the boom.

G10-55A & G12-55A AccuPlace

Boom

9. Loosen and remove all the wear pads from the front of the second boom section. Tag each pad, backing plate, shim and bolts from each location.

10. Place a sling around the third boom section, lift and slowly pull the third and fourth boom sections (7) approximately half way out of the second boom section. Lower the third and fourth boom sections onto a suitable support.

11. Relocate the sling or using two slings for better stability, balance the two boom sections and slowly pull them out of the second boom section being careful not to damage any surrounding components.

MY1690

12. Remove the chain (8) from the second boom section to the third boom section after the boom sections are free from each other.

13. Lower the third and fourth boom sections onto a suitable support.

3.3.4 Fourth Boom Section Removal

1. Remove the bottom rear and side bearing pads from the fourth boom section. Tag each pad, backing plate, shim and bolts from each location.

2. Loosen and remove the 3/4 in. chain (9) through the rear of the fourth boom section.

4. Loosen and remove the front wear pads and supports from the third boom section. Tag each pad, backing plate, shim and bolts from each location.

5. Carefully pull the fourth boom section out of the third boom section, taking care to protect the chains.

6. Disconnect the chains when the boom sections are free from each other.

7. Place the fourth boom section onto suitable supports.

If the hydraulic sub-assembly (11) is going to be removed:

MX0390

8. Remove the guide bracket from the front of the hydraulic sub-assembly.

9. Remove the hardware securing the hydraulic subassembly to the front of the boom.

10. Install a sling on the hydraulic sub-assembly at the rear of the boom. Slowly pull it loose from the bottom bracket located on the bottom plate of the fourth boom section.

11. When the sub-assembly is approximately 25% free of the boom, fasten the two hose carriers together (using nylon tie-wraps or nylon straps) to prevent them from separating.

Note: Do not wrap the hose carrier since it will not prevent the two hydraulic carriers from moving apart sideways.

12. Continue to withdraw the sub-assembly, fastening the hydraulic carriers together as they are removed.

13. When the hydraulic carrier is approximately 75% tied together, pull the assembly free of the boom.

3.3.5 Fourth Boom Section Installation

MX0380

3. Loosen and remove the retract chain roller (10) at the rear of the third boom section.

G10-55A & G12-55A AccuPlace

1. Clean and lubricate the inside of the boom sections where the hydraulic sub-assembly rides (if removed).

2. Using a sling, lift the balanced hydraulic subassembly and slowly insert it into the fourth boom section.

3. As the first tie wrap nears the boom, remove the tie wrap and continue inserting the sub-assembly and removing each tie wrap until the sub-assembly is fully inserted.

3.5

Boom

Note: Be certain the hydraulic sub-assembly locks into place on the pin bracket at the bottom of the fourth boom section.

4. Reconnect the hydraulic hoses and any optional circuits.

5. Install the guide bracket and hardware to secure the hydraulic sub-assembly to the front of the boom.

6. Reinstall the hose take-up compression spring. Torque the jam nut to 100 lb-ft. There should be a 1 in. (25 mm) gap from the back of the jam nut to the end of the threads on the hose take-up weldment.

7. Install the wear pads, backing plates and shims to the top, bottom and sides of the fourth boom section. Do not shim or tighten the bolts at this time.

8. Attach the chain clevis and the keeper plate to the inside rear of the boom.

9. Install the grease fitting extensions for the bottom rear wear pads.

10. Lubricate the extend chain completely. Make sure the chain is inspected and is in good working condition. See Section 3.4.4, “Chain Lubrication.”

11. Attach the chain to the chain clevis.

12. Attach the chain clevis to the top of the fourth boom section.

13. Grease the inside of the third boom section on areas where the fourth boom section wear pads will slide.

14. Using a suitable sling, balance the fourth boom section and carefully slide 3-4 ft (1-1,5 m) into the front of the third boom section. Set the fourth boom section head onto suitable supports and reset sling under the boom head. Carefully slide the fourth boom section into the third boom section. Leave 6-8 in (15-20 cm) of the fourth boom section out to be able to install wear pads on the front of the third boom section.

15. With the boom head still supported, install the top wear pads, washers and bolts in the front of the third boom section. Remove the boom head from supports and install the remaining wear pads inside the third boom section. Do not shim or tighten the bolts at this time.

16. Install the grease fittings for the wear pad and chain roller assembly.

3.3.6 Third & Fourth Boom Section

Installation

1. Install the top, bottom and side rear wear pads onto the third boom section. Do not shim or tighten the bolts at this time.

2. Grease the inside of the second boom section on areas where the third section wear pads will slide.

3. Install the grease fittings for the wear pad and chain roller assembly.

4. Install the chain clevis to the rear of the third boom section.

5. Install the chain roller (1) at the bottom rear of the boom.

6. Install the chain roller at the top front of the boom.

7. Lay out and lubricate the retract chain. Make sure the chain has been inspected and meets the adjustment parameters in Section 3.4.1, “Boom Chain Inspection.”

8. Connect the retract chain (2) to the clevis at the rear of the fourth boom section.

MX0380

9. Connect the chain to the chain clevis and the clevis to the chain adjustment block. Adjust the nut until the gap between the nut and the washer is 1/8 in. (3,175 mm). Torque the locknut to 100 lb-ft (135 Nm).

10. Lay out and lubricate the two extend chains. Make sure the chains have been inspected and meets the adjustment parameters in Section 3.4.1, “Boom Chain Inspection.”

11. Attach the rear chain clevis to the chain.

12. Using a suitable sling, balance the fourth and third boom sections and carefully slide 3-4 ft (1-1,5 m) into the front of the second boom section. Set the fourth and third boom sections onto suitable supports and reset the sling under the boom head. Carefully slide the fourth and third boom sections into the second boom section. Leave 6-8 in (15-20 cm) of the third boom section out to be able to install the wear pads on the front of the second section.

13. With the boom still supported, install the top wear pads in the front of the second boom section.

3.6

G10-55A & G12-55A AccuPlace

Boom

Remove the boom from supports and install the remaining wear pads to the second boom section. Do not shim or tighten bolts at this time.

14. Install the grease fittings for the wear pad and chain roller assembly.

3.3.7 Second Boom Section Installation

1. Install the top, bottom and side rear wear pads onto the second boom section. Do not shim or tighten the bolts and this time.

2. Lubricate the inside of the first boom section on areas where the second boom section wear pads will slide.

3. Attach the chain clevis (3) to the rear of the third boom section.

4. Using a suitable sling, balance the second, third and fourth boom sections and carefully slide 3-4 ft into the front of the first boom section. Set the second, third and fourth boom sections on a suitable support and reset the sling under the boom head of the fourth boom section. Carefully slide the three boom sections into the first boom section. Leave 6-8 in of the two boom sections out to be able to install the wear pad block and the wear pads in the front of the first boom section.

5. Install the chain adjustment block (4) to the bottom of the boom.

MX0440

6. With the boom still supported, install the top wear pads in the front of the first boom section. Remove the boom from supports and install the remaining wear pads to the first boom section. Do not shim or tighten bolts at this time.

7. Lubricate the retract chain on the bottom of the second boom section.

8. Install the lube fittings to the wear pad and chain roller assembly.

9. Connect the chain clevis (5) to the second boom section.

10. Assemble the rear bottom chain roller to the second boom section.

11. Shim all wear pads needed to obtain the minimum gap of 1/16 in (1,6 mm). Tighten all wear pad bolts to the correct values. Refer to Section 3.7, “Boom Wear Pads.”

12. Install the hose sheave to the second boom section.

13. Attach the hoses, and optional auxiliary hoses and electrical cable to the hose carrier at the rear of the boom.

14. At the rear of the boom, install the bracket (6) to the back of the hose carrier.

MAP0670

15. Install the hose guide bracket for the electric and hydraulic options at the rear of the boom.

16. Attach the chain clevis to the chain.

17. Install the hoses to the hose carrier at the rear of the boom.

18. Install the hose guide bracket to the rear of the second boom section.

19. Install the optional hydraulics and electrical cables if equipped.

20. Connect the hose assembly to the take-up weldment.

MY1720

G10-55A & G12-55A AccuPlace

3.7

Boom

21. Install the top front chain roller (7) to the second and third boom sections.

MAP0740

22. Install the cushion clamps around the hoses on the first boom section.

23. Connect the top front chain clevises to the chains, then connect the chains to the first and second boom sections.

24. Adjust the retract chain (8) at the bottom front of the first boom section to 2 7/8 in. (73 mm) for the initial setup.

25. Install the auxiliary hydraulic hoses and electrical cables to the boomhead of the fourth boom section.

26. Using a suitable sling, install the tilt cylinder to the front of the boom.

27. Using a suitable sling, install the extend/retract cylinder and support to the second and first boom section.

28. Reconnect the latch on the Boom Length Sensor cable to the third boom section. Refer to Section

9.11.13, “Boom Length Sensor.”

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, chock the wheels and shut the engine OFF.

2. 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 the boom pivot pin.

3. With the sling still in place, install the compensation cylinder, pins and bolts.

4. With the sling still in place, install the rod end of the left lift/lower cylinder, pin and lock bolt. Repeat for the right side lift/lower cylinder.

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

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

5. Uncap and reconnect the previously labeled hydraulic hoses to the extend/retract cylinder.

6. Uncap and connect any remaining hydraulic fittings to their appropriate locations.

7. Recheck the wear pad gaps to ensure they meet the minimum gap requirement. Shim if necessary.

8. Ensure that the boom chains are properly adjusted. Refer to Section 3.5, “Boom Section Separation Adjustment.”

9. Install and reconnect the boom angle sensors to both the left and right side of the boom. Refer to Section 9.11.12, “Boom Angle Sensors.”

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

11. Start the engine and operate all boom functions several times. Check for leaks, and check the hydraulic fluid level in the reservoir; add fluid if required.

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

13. Close and secure the engine cover.

3.8

G10-55A & G12-55A AccuPlace

+ 200 hidden pages