Onan 2400, 3500, HomeSite Power 2400, HomeSite Power 3500, 2EGMBB-5267 Service Manual

Service Manual

HomeSite Power

2400 (2EGMBB-5267) 3500 (2.5EGMBG-5268) Portable Generator Set

Printed in U. S. A. 03-06 914-0500

SAFETY PRECAUTIONS

a

Thoroughly read the OPERATOR’S MANUAL before operating the generator set. Safe operation and top performance can only be attained when equipment is operated and maintained properly.

The following symbols, found throughout this manual, alert you to potentially dangerous conditions to operators, service personnel and equipment.

This symbol alerts you to an

immediate hazard that will result in severe personal injury or death.

This symbol alerts you to a

hazard or unsafe practice that can result in severe personal injury or death.

This symbol alerts you to a

hazard or unsafe practice that can result in personal injury or damage to equipment or property.

Electricity, fuel, exhaust, moving parts and batteries present hazards against which precautions must to taken to prevent severe personal injury or death.

Exhaust Gas Is Deadly

• Operate the generator set outdoors only.

Stay away from the exhaust outlet.

• Make sure generator set exhaust will not

enter windows, doors, vents or air intakes of adjacent buildings, vehicles or boats.

• NEVER USE THE GENERTOR SET

INSIDE a home, garage, crawl space, barn, shed, cabin, boat, boat house, RV or tent, or in a confined outdoor space such as an alley, ditch, parking garage or courtyard, or in any other space where exhaust can accumulate. Note that HAZARDOUS CARBON MONOXIDE LEVELS FROM ENGINE EXHAUST CAN ACCUMULATE INDOORS EVEN WHEN ALL WINDOWS AND DOORS ARE OPEN AND FANS ARE RUNNING.

Gasoline is Flammable / Explosive

• Refuel the generator set outdoors only.

• Static electric sparks caused by fuel flowing

through a service station pump nozzle can ignite gasoline. Never fill the generator set with a service station pump nozzle. Instead, fill a safety tank sitting on the ground and then slowly transfer fuel to the generator set from the safety tank.

• DO NOT fill fuel tanks while the engine is

running. A hot engine can ignite the fuel.

• To prevent fire due to fuel leakage, always

close the fuel valve and let the generator set cool before transporting it or storing it in a confined space.

• DO NOT SMOKE OR ALLOW AN OPEN

FLAME near the generator set. Keep flames, sparks, electrical switches, pilot lights, electrical arcs, arc-producing equipment and all other sources of ignition well away.

Generator Voltage is Deadly

• DO NOT CONNECT THE GENERATOR

SET DIRECTLY TO ANY BUILDING ELECTRICAL SYSTEM. Back-feed could cause electrocution of utility line workers and damage to equipment. An approved switching device must be used to prevent interconnections. A trained and experienced electrician must make electrical connections when the generator set is used for emergency power.

• Make sure clothing, shoes and skin are dry

when handling electrical equipment.

• Never operate the generator set in rain or

snow or when it is sitting on wet ground.

Moving Parts Can Cause Severe

Personal Injury or Death

• Before performing any maintenance on the

generator set, disconnect the spark plug wire.

• Always keep hands away from moving parts.

• Do not wear loose clothing or jewelry while

servicing the generator set. Loose clothing and jewelry can become caught in moving parts. Jewelry can short out electrical contacts causing sparks, flame and electrical shock.

• Make sure that fasteners and clamps on the

generator set are tight. Keep guards in position over fans, rotors, etc.

SAFETY PRECAUTIONS

b

Battery Gases are explosive

• Wear safety glasses when servicing

batteries.

• Do not smoke.

• To reduce arcing when disconnecting or

reconnecting battery cables, always

disconnect the negative (–) cable of the

battery first and reconnect it last.

General Precautions

• Keep children away from the generator set.

• Wear hearing protection when near an

operating generator set.

• Keep a multi-class ABC fire extinguisher

readily at hand. Class A fires involve ordinary combustible materials such as wood and cloth. Class B fires involve combustible and flammable liquids and gaseous fuels. Class C fires involve live electrical equipment. (ref. NFPA No. 10)

•

Benzene and lead may be found in gasoline and have been identified by some state and federal agencies as causing cancer or reproductive toxicity. Do not ingest, inhale or contact gasoline.

• Used engine oils have been identified by

some state and federal agencies as causing cancer or reproductive toxicity. Do not ingest, inhale or contact used engine oil or its vapors.

• Keep the generator set clean and dry at all

times. Excess grease and oil can catch fire and/or accumulate dirt, which can cause overheating.

• Do not store anything on the generator set,

such as oil cans, oily rags, chains or wooden blocks. A fire could result or operation could be adversely affected

• Do not work on the generator set when you

are mentally or physically fatigued or have consumed alcohol or drugs.

Failure to properly follow instructions and precautions can cause you to be seriously hurt or killed.

Follow the procedures and precautions in this manual carefully.

Improper service or repairs can create an unsafe condition that can cause your customer or others to be seriously hurt or killed.

Follow the procedures and precautions in this manual and other service materials carefully.

TABLE OF CONTENTS

c

Title Page

SECTION 1 INTRODUCTION 1

1-1 Generator Components 1 1-2 Specifications 3

SECTION 2 DIMENSIONS AND TORQUE 4

2-1 Engine Dimensions 4 2-2 Generator Dimensions 6 2-3 Torque Specification 6 2-4 Standard Torques Specification 6

SECTION 3 MAINTENANCE 7

3-1 Maintenance Schedule 7 3-2 Engine Oil 8 3-3 Air Cleaner 9 3-4 Fuel Sediment Cup Cleaning 10 3-5 Spark Arrester 10 3-6 Spark Plug 11 3-7 Valve Clearance 12 3-8 Governor 12

SECTION 4 DISASSEMBLY AND SERVICE 13

4-1 Troubleshooting 13

4-1-1 Hard Starting 13 4-1-2 Low Power 14 4-1-3 Speed Unstable 15 4-1-4 Low Speed Voltage 16 4-1-5 Exhaust Color Abnormal 17 4-1-6 No AC Output Voltage 18 4-1-7 No DC Output Voltage 18

4-2 Preparing to Service 19

4-2-1 Safety Considerations 19

4-2-2 Special Tools 19 4-3 Disassembly Chart 20 4-4 Engine 21

4-4-1 Crankshaft / Pistion 21

4-4-2 Flywheel 27

4-4-3 Cylinder head / Valves 29

4-4-4 Recoil Starter / Fan Cover 33

4-4-5 Air Cleaner 36

4-4-6 Carburetor 37 4-5 Generator 38

4-5-1 Fuel Tank 38

4-5-2 Muffler 39

4-5-3 Generator 40

4-5-4 Control Panel 44

SECTION 5 WIRING DIAGRAMS 50

5-1 The Wiring Diagram of 2400 50 5-2 The Wiring Diagram of 3500 51

SECTION 1. INTRODUCTION

- 1 -

1-1 Generator Components

ON/OFF

SWITCH

DC BREAKER RESET SWITCH

AC VOLTMETER

12 VOLT DC

TERMINALS

CHOKE LEVER

FUEL

V

ALVE

AIR CLEANER

RECOIL STARTER GRIP

FUEL GAUGE

FUEL TANK CAP

EARTH

GROUND

LUG

AC BREAKER

RESET SWITCH

120VAC RECEPTACLE

(GFCI)

FIGURE 1. 2400 COMPONENT LOCATIONS

SPARK PLUG BOOT

MUFFLER

SECTION 1. INTRODUCTION

- 2 -

FIGURE 2. 3500 COMPONENT LOCATIONS

MUFFLER

SPARK PLUG BOOT

ON/OFF SWITCH

DC BREAKER RESET SWITCH

AC VOLTMETER

12 VOLT DC

TERMINALS

CHOKE LEVER

FUEL

V

ALVE

AIR CLEANER

RECOIL STARTER GRIP

FUEL GAUGE

FUEL TANK CAP

EARTH

GROUND

LUG

AC BREAKER

RESET SWITCH

120VAC RECEPTACLE

(GFCI)

AC RECEPTACLE

(240VAC)

AC BREAKER

RESET SWITCH

VOLTAGE SELECT

SWITCHE

SECTION 1. INTRODUCTION

- 3 -

1-2 Specifications

GENERATOR

2400 3500

AC OUTPUT:

Frequency (Hertz) 60 Hz 60 Hz

Voltage 120 Volts 120 / 240 Volts

Rated Power 2000 Watts 2500 Watts

Rated Current 16.6 Amps 20.8 / 10.4 Amps

DC OUTPUT: 12 VDC / 8.3 Amps 12 VDC / 8.3 Amps

ENGINE

Engine Type Single Cylinder, Forced Air Cooling, 4-Stroke

Engine Speed (RPM) 3600 3600

Fuel Gasoline Gasoline

Engine Oil Capacity 0.63 US qt (0.6 L) 0.63 US qt (0.6 L)

Spark Plug Type F7RTC F7RTC

Spark Plug Gap 0.028 in. (0.7 mm) 0.028 in. (0.7 mm)

Engine Valve Lash (Intake / Exhaust)

0.0039 /0.006 inches (0.10/ 0.15 mm)

0.0039 /0.006 inches (0.10 / 0.15 mm)

Ignition Timing (fixed) 20° BTDC 20° BTDC

Starting System Recoil Recoil

Displacement 197 cc 197 cc

GENERATOR SET

Dry Weight 99.9 lb (45 kg) 106.6 lb (48 kg)

Dimensions:

Length 24.1 inches (612 mm) 24.1 inches (612 mm)

Width

19.6 inches (497 mm） 19.6 inches (497 mm）

Height 19.3 inches (490 mm) 19.3 inches (490 mm)

Fuel Tank Capacity 4.0 US gal (15 L) 4.0 US gal (15 L)

Operating Time at Rated Output 13 Hours 12 Hours

SECTION 2. DIMENSIONS AND TORQUE

- 4 -

2-1 Engine Dimensions

2400

Part Item

Factory Specification Allowable limit

Maximum speed 3750±150 rpm Idle speed 1400±150 rpm -

Engine

Cylinder compression 6.0-8.5 kg/cm (1.5 –

2.13 kg/in)at 600 rpm

-

Cylinder Sleeve I.D.

68.015 mm (2.6778 in)

68.165 mm (2.6837 in)

Cylinder head Warpage

-

0.10 mm

(0.004 in)

Skirt O.D. 67.985 mm

(2.6766 in)

67.845 mm (2.6711 in)

Piston-to-cylinder clearance

0.030-0.050 mm

(0.0012-0.0020 in)

0.12 mm

(0.005 in)

Piston pin bore I.D. 18.002 mm

(0.7087 in)

18.048 mm (0.7105 in)

Pin O.D. 17.998 mm

(0.7086 in)

17.954 mm (0.7068 in)

Piston

Piston -to- piston pin bore clearance

0.004-0.016 mm

(0.00016-0.0006 in)

0.06 mm (0.002in)

Ring side clearance Top/second/oil

0.015-0.045 mm

(0.0006-0.0018 in)

0.15 mm

(0.0006 in)

Ring end gap Top/ second Oil

0.2-0.4 mm

(0.008-0.016 in)

1.0 mm

(0.04 in)

Piston rings

Ring Width Top/ second

Oil

1.5 mm

(0.06 in)

2.5 mm

(0.10 in)

1.37 mm

(0.054 in)

2.37 mm

(0.093 in) Small end I.D. (Pin End)

18.007 mm (0.7089 in)

18.07 mm (0.711 in)

Big end I.D. (Crankshaft)

30.015 mm (1.1817 in)

30.0667 mm (1.1837 in)

Big end oil clearance

0.030-0.050 mm

(0.0012-0.0020 in)

0.12 mm

(0.0048 in)

Connecting rod

Big end side clearance

0.1-0.7 mm

(0.004-0.028 in)

1.1 mm

(0.043 in)

Crankshaft

Crankshaft O.D. (Connecting rod Big end)

29.985 mm (1.181 in)

29.92 mm (1.178 in)

SECTION 2. DIMENSIONS AND TORQUE

- 5 -

2400

Part Item Factory Specification Allowable limit

Valve Lash IN

0.10±0.02 mm

(0.004±0.001 in)

-

EX 0.15±0.02 mm

(0.006±0.001 in)

-

Stem O.D. IN

5.48 mm

(0.216 in)

5.318 mm

(0.2094 in)

EX 5.47 mm

(0.215 in)

5.275 mm

(0.2077 in)

Guide I.D. IN/ EX 5.50 mm

(0.217 in)

5.572 mm

(0.2194 in)

Stem clearance IN

0.02-0.044 mm

(0.0008-0.0017 in)

0.10mm

(0.004 in)

EX 0.06-0.087 mm

(0.0024-0.0034 in)

0.12 mm

(0.005 in)

Seat width 0.8 mm

(0.03 in)

2.0mm

(0.08 in)

Valves

Spring fee length 30.0 mm

(1.18 in)

28.5 mm

(1.122 in)

Cam height IN 27.7 mm

(1.09 in)

27.45 mm (1.081 in)

EX 27.75 mm

(1.093 in)

27.5 mm

(1.083 in)

Camshaft

Camshaft O.D.

13.984 mm (0.5506 in)

13.916 mm (0.5479 in)

Crankcase cover

Camshaft-holder I.D. 14.0 mm

(0.55 in)

14.048 mm (0.5531 in)

Spark plug Gap 0.7-0.8 mm

(0.028-0.031 in)

-

Resistance Primary coil 0.8-1.0 Ω - Secondary coil 5.9-7.1 KΩ -

Ignition coil

Air gap (at flywheel) 0.4±0.2 mm

(0.016±0.008 in)

-

SECTION 2. DIMENSIONS AND TORQUE

- 6 -

2-2 Generator Dimensions

2400 (2.0 kW)

Part Item Factory specification Main winding (R / Bu) Resistance 0.51-0.53 Ω Field winding Resistance 40-50 Ω Exciter winding (Bu / Bu) Resistance 3.1-3.3 Ω DC winding (G / G) Resistance 0.4-0.6 Ω Carbon brush Brush length 5-9 mm

3500 (2.5 kW)

Part Item Factory specification Main windingⅠ(Br / W)

Resistance 0.76-0.79 Ω

Main windingⅡ(R / Bu)

Resistance 0.76-0.79 Ω

Field winding Resistance 35-45 Ω Exciter winding (Bu / Bu) Resistance 1.5-1.7 Ω DC winding (G / G) Resistance 0.4-0.6 Ω Carbon brush Brush length 5-9 mm

2-3 Torque Specification

2-4 Standard Torques Specification

Part Fastener size Torque values N· m (kg· cm, lb·ft) Cylinder head bolt 8×1.25×55 mm 26-28 (260-280, 18.8-20.2) Pivot bolt 6×0.5 mm 8-12 (80-120, 5.8-8.7) Pivot adjusting nut 6×1.25 mm 22-26 (220-260, 15.9-18.8) Crankcase cover bolt 8×1.25×32 mm 24-26 (240-260, 17.4-18.8) Connecting rod bolt 7×1.25 mm 12-14 (120-140, 8.7-17.4) Air cleaner wing nut 6×1.0 mm 7-10 (70-100, 5.1-7.2) Air cleaner mounting nut 6×1.0 mm 7-10 (70-100, 5.1-7.2) Muffler mounting bolt 8×1.25 mm 20-28 (200-280, 14.5-20.2) Oil drain bolt 10×1.5 mm 20-25 (200-250, 14.5-18.1) Fuel tank mounting bolt/ nut 6×1.0 mm 8-12 (80-120, 5.8-8.7) Fuel valve joint nut 10×1.25 mm 20-25 (200-250, 14.5-18.1) Oil level switch mounting nut 10×1.25 mm 8-12 (80-120, 5.8-8.7) Flywheel mounting nut 14×1.25 mm 80-90 (800-900, 58-865.3)

5 mm bolt, nut 4-7 (40-70, 2.9-5.1) 6 mm bolt, nut 8-12 (80-120, 5.8-8.7) 8 mm bolt, nut 20-28 (200-280, 14.5-20.2) 10 mm bolt, nut 35-40 (350-400, 14.5-20.2)

Standard torque values

12 mm bolt, nut 50-60 (500-600, 36.2-43.4)

SECTION 3. MAINTENANCE

- 7 -

3-1 Maintenance Schedule

Periodic maintenance is essential for top performance. Use Table 3 as a guide. Under hot or dusty operating conditions some maintenance operations should be performed more frequently, as indicated by the footnotes in the table.

Keep a log of maintenance performed and the hours run. Recording maintenance will help you keep it regular and provide a basis for supporting warranty claims.

Accidental starting of the generator set during maintenance can cause severe personal injury or death. Before performing maintenance, disconnect the spark plug wire from the spark plug.

A hot generator set can cause

severe burns. Always allow the generator set to cool before performing any maintenance or service.

TABLE 3. PERIODIC MAINTENANCE SCHEDULE

1.See GENERAL INSPECTIONS.

2.Service more frequently when used in dusty environments.

3. These items must be performed by a trained and experienced mechanic (authorized Onan dealer).

SERVICE INTERVAL

SERVICE THESE ITEMS

EACH

USE

FIRST

MONTH OR

20 HOURS

EVERY 3

MONTHS OR

50 HOURS

EVERY

MONTH

EVERY 6

MONTHS OR

100 HOURS

EVERY

YEAR OR

300 HOURS

General Inspection ×1

Check Oil Level ×

Test GFCI ×

Change Engine Oil × ×

Clean Air Cleaner ×2

Clean Cylinder Cooling Fins ×2

Clean Spark Plug ×

Clean the Spark Arrestor x

Clean Fuel Sediment Cup ×3

Clean Fuel Tank ×3

Adjust Valve Clearance ×

3

Check fuel line Every 2 years(Replace if necessary) 3

SECTION 3. MAINTENANCE

- 8 -

3-2 Engine Oil

NOTE: Drain the oil while the engine is still warm to assure rapid and complete draining.

1) Remove the oil filler cap and drain plug.

2) Drain the oil from the crankcase.

3) Reinstall the drain plug securely.

4) Add new oil up to the bottom edge of the oil filler hole with the engine stopped and in a level position.

5) Reinstall the oil filler cap and tighten it securely.

Used motor oil may cause skin

cancer if repeatedly left in contact with the skin for prolonged periods. Thoroughly wash your hands with soap and water as soon as possible after handling used oil.

Engine Oil Capacity 1.16 US qt (1.1 L)

Oil filler cap

Oil drain bolt (M10)

Lower level

RECOMMENDED ENGINE OIL:

SAE 10W-30 is recommended for general, all temperature use: service classification

SG·SF/CC·CD.

20W-40

10W-30

10W-40

20W-50

SECTION 3. MAINTENANCE

- 9 -

3-3 Air Cleaner

A dirty air cleaner will restrict air flow to the carburetor. To prevent carburetor malfunction, service the air cleaner regularly. Service more frequently when operating the generator in extremely dusty areas.

Using gasoline or flammable

solvent to clean the filter element can cause a fire or explosion. Use only soapy water or nonflammable solvent.

Never run the generator without the air cleaner. Rapid engine wear will result.

1) Remove the cleaner cover by unsnapping the

two spring clips. Clean more often in dusty environments

2) Remove the two foam filter elements and

thoroughly wash them with soap and water. Let them dry thoroughly.

3) Knead in 1 teaspoon (5 cm

3

) of clean engine oil into each foam filter element. The oil should be distributed evenly throughout each filter elements.

4) Reinstall the filter elements, the gray filter first (finer pores) and then the black filter (larger pores).

5) Secure the cover with the spring clips.

AIR CLEANER ELEMENT

SOAP & WATER

DRY

ENGINE OIL

S

Q

UEEZE

AIR CLEANER COVER

CLIP

SECTION 3. MAINTENANCE

- 10 -

3-4 Fuel Sediment Cup Cleaning

The sediment cup prevents dirt or water which may be in the fuel tank from entering the carburetor. If the engine has not been run for a long time, the sediment cup should be cleaned.

1) Turn the fuel valve to the OFF position. Remove the sediment cup, and o-ring.

2) Clean the sediment cup, and o-ring, in nonflammable or high flash point solvent.

3) Reinstall o-ring, and sediment cup.

4) Turn the fuel valve ON and check for leaks.

Gasoline is extremely flammable and is explosive. Do not smoke or allow flames or sparks in the area.

After reassembly, check for leaks, and make sure the area is dry before starting the engine.

3-5 Spark Arrester

A hot muffler can cause severe burns. Allow the generator set to cool before servicing the muffler.

Refer to MAINTENANCE SCHEDULE for scheduled spark arrester cleaning. After letting the generator set cool down, remove the spark arrester screen. Inspect for damage, and replace if defective. Clean any deposits on the screen with a wire brush. Reinstall the spark arrester, and tighten the screw securely.

FUEL FILTER

SEDIMENT CUP (10 mm)

FUEL VALVE

O-RING

SEDIMENT CUP

SECTION 3. MAINTENANCE

- 11 -

3-6 Spark Plug

To ensure proper engine operation, the spark plug must be properly gapped and free of deposits.

If the engine has been running, the spark plug and muffler will be very hot. Be careful not to touch the muffler or spark plug.

1) Turn off generator.

2) Remove the spark plug cap.

3) Clean any dirt from around the spark plug base.

4) Use the wrench supplied in the tool kit to remove the spark plug.

5) Visually inspect the spark plug. Discard it if the insulator is cracked or chipped. Clean the spark plug with a wire brush if it is to be reused.

6) Measure the plug gap with a feeler gauge. Correct as necessary by carefully bending the side electrode.

The gap should be: 0.70-0.80 mm (0.028-0.031 in).

7) Check that the spark plug washer is in good condition, and thread the spark plug in by hand to prevent cross-threading.

8) After the spark plug is seated, tighten with a spark plug wrench to compress the washer.

If installing a new spark plug, tighten l/2 turn after the spark plug seats to compress the washer. If reinstalling a used spark plug, tighten l/8 - l/4 turn after the spark plug seats to compress the washer.

The spark plug must be securely tightened. An improperly tightened spark plug could damage the engine.

Never use spark plugs which have an improper heat range. Use only the recommended spark plugs or equivalent.

PLUG WRENCH

PLUG CAP

0.7-0.80mm

SIDE ELECTRODE

METAL BRUSH

SPARK PLUG TORQUE

(20N

•m-25N•m)

SECTION 3. MAINTENANCE

- 12 -

3-7 Valve Clearance

Valve clearance inspection and adjustment must be performed with the engine cold.

1) Remove the cylinder head cover, and set the

piston at top dead center of the compression stroke (both valves fully closed). Pull the starter until the piston is at top dead center of the compression or exhaust stroke.

2) Insert a feeler gauge between the rocker arm

and valve to measure valve clearance.

3) If adjustment is necessary, proceed as follows:

a) Hold the rocker arm pivot and loosen the

pivot lock nut.

b) Turn the rocker arm pivot to obtain the

specified clearance.

c) Retighten the lock nut while holding the

rocker arm pivot.

d) Recheck valve clearance after tightening

the lock nut.

3-8 Governor

1) Take down the fuel tank.

2) Loosen the nut on the governor arm pinch bolt.

3) Move the arm until the throttle is completely open, and hold it in that position.

4) Rotate the governor arm shaft as far as it will go in same direction it was just moved by the governor arm, and then tighten the governor arm pinch bolt.

5) Whether check the arm and throttle move smoothing.

6) Install the fuel tank.

7) Start the engine and adjust the limiting screw to produce the standard until the engine warm up to normal operating temperature.

IN.

0.10±0.02 mm (0.004±0.001 in)

Standard valve clearance

EX.

0.2±0.02 mm (0.008±0.001 in)

Idle speed

3600±150rpm

ROCKER ARM

PIV

O

T

LOCK NUT 10N

•m-140N•m

To increase valve clearance, screw lock nut out. To decrease valve clearance, screw lock nut in.

GOVERNOR SPRING

THROTTLE

GOVERNOR

A

RM SHAFT

GOVERNOR ARM

ANTI-SURGE SPRING

NUT

LIMITING SCREW

GOVERNOR ARM PINCH BOLT

nut

SECTION 4. DISASSEMBLY AND SERVICE

- 13 -

(TRY AGAIN AFTER A FEW MINUTES)

4-1 Troubleshooting 4-1-1 Hard Starting

(SEE 4-4-1)

(SEE 4-4-3)

(SEE 3-7)

(SEE 4-4-1)

(SEE 4-5-4)

(SEE 4-4-2)

(SEE 3-6)

(SEE 3-2)

HARD ST ARING

FUEL SYSTEM

IGNITION SYSTEM

COMPRESSION SYSTEM

(SEE 3-3)

(SEE 4-4-6)

(SEE 3-4)

(ADD FUEL INTO FUEL TANK)

FUEL low

FUEL FILTER clogged

CARBURETOR out o f adjustment

A

IR FILTER dirt

y

OIL low

SPARK PLUG GAP incorrect

SPARK PLUG CAP fault

y

IGNITION COIL GAP incorrect

IGNITION COIL fault

y

START SWITCH faulty

OIL ALERT SYSTEM faulty

V

ALVE LASH incorrect

CYLINDER HEAD GASK ET faulty

CYLINDER HEAD BOLT faulty

V

ALVE fault

y

CYLINDER / PISTON / PISTON RING worn

CAMSHAFT wore

ENGINE FLOODED too much fuel

SECTION 4. DISASSEMBLY AND SERVICE

- 14 -

(ADD CLEAN FRESH FUEL INTO TANK)

4-1-2 Low Power

(CLEAN)

(SEE 4-5-2)

(SEE 3-8)

(SEE 4-4-6)

(MOVE TO “RUN” POSITION)

(SEE 3-3)

(SEE 4-4-1)

(SEE 3-6)

(SEE 4-4-1)

(SEE 3-7)

(CLEAN)

(SEE 4-4-3)

(SEE 3-4)

Low Power

FUEL SYSTEM

IGNITION SYSTEM

COMPRESSION SYSTEM

CARBURETOR out of adjustment

FUEL FILTER clogged

CHOKE ROD not open

A

IR FILTER dirt

y

SPARK PLUG fault

y

CAMSHAFT worn

CYLINDER / PISTON / PISTON RING worn

V

ALVE LASH out of Spec

COOLING FAN dirt

y

V

ALVE SEAT worn or damaged

COOLING CYLINDER FINS dirty

MUFFLER clogged

GOVERNOR out of adjustment

OTHER

FUEL poo

r

(REMOVE EXTRA LOADS)

ELECTRICAL LOADS too high

SECTION 4. DISASSEMBLY AND SERVICE

- 15 -

4-1-3 Speed Unstable

(SEE 4-4-2)

(SEE 4-4-1)

(SEE 3-4)

(ADD NEW FUEL INTO FUEL TANK)

(SEE 4-4-6)

(SEE 3-8)

(REPLACE)

SPEED UNSTABLE

FUEL SYSTEM

GOVERNOR SYSTEM

COMPRESSION SYSTEM

FUEL low / poor quality / contaminated

FUEL FILTER clogged

CARBURETOR clogged

GOVERNOR out of adjustment

A

NTI-SURGE SPRING incorrect

SPARK PLUG spark plug wire fault

y

CAMSHAFT worn

(ADD NEW OIL)

OTHER

OIL low level

(REMOVE EXTRA LOADS)

ELECTRICAL LOADS too high

SECTION 4. DISASSEMBLY AND SERVICE

- 16 -

4-1-4 Low Speed / Voltage

(SEE 4-5-2)

(SEE 3-8)

(PUSH CHOKE ROD)

(SEE 4-4-6)

(SEE 3-3)

LOW SPEED / VOLTAGE

FUEL SYSTEM

GOVERNOR SYSTEM

CARBURETOR has wate

r

CHOKE LEVER not open

A

IR FILTER dirt

y

GOVERNOR out of adjustment

A

NTI-SURGE SPRING incorrect

MUFFLER clogged

A

LTERNATOR tem

p

erature is too high

OTHER

(REPLACE)

(SEE 4-5-3) (CLEAN ALTERNATOR FAN AND END COVER)

(REMOVE EXTRA LOADS)

ELECTRICAL LOADS too high

(ADD NEW FUEL)

FUEL poor / contaminated

SECTION 4. DISASSEMBLY AND SERVICE

- 17 -

4-1-5 Exhaust Color Abnormal

(SEE 3-2)

(SEE 4-4-1)

(CHANGE TO FRESH FUEL)

(ADD FRESH FUEL)

(NORMAL WHEN STARTING)

(REMOVE EXTRA LOAD)

(SEE 4-4-6)

(SEE3-3)

EXHAUST COLOR ABNORMAL

BLACK

WHITE

CARBURETOR fault

y

LOAD excessive

A

IR FILTER dirt

y

ENGINE temperature is too low

FUEL contaminated

FUEL contaminated with oil

CYLINDER / PISTON / PISTON RING worn

OIL too much

BLUE

(CLEAN BREATHER)

BREATHER icing issue

SECTION 4. DISASSEMBLY AND SERVICE

- 18 -

4-1-6 No AC Output Voltage

4-1-7 No DC Output Voltage

(SEE 4-5-3)

(CHECK IT AND ADJUST)

NO AC OUTPUT VOLTAGE

STATOR MAIN COIL defective

BRUSH defective

ENGINE SPEED abnormal

EXCIT ATION VOLTAGE too low

A

VR defective

(RESET BREAKERS)

BREAKER tripped

(RESET BREAKERS)

NO DC OUTPUT VOLTAGE

BREAKER tripped

OTHER REASON

SECTION 4. DISASSEMBLY AND SERVICE

- 19 -

4-2 Preparing to Service 4-2-1 Safety Considerations

There are hazards in servicing gensets. Study Safety precautions and become familiar with the hazards listed in table 4-1. Note the following safeguards and ways of avoiding hazards.

• Use personal protection: Wear appropriate

protective safety equipment, such as safety shoes and safety glasses.

• Do not wear rings or jewelry and do not wear loose or damp clothing that might get caught in equipment or conduct electricity.

• Reduce the hazard: A safety, order workshop

area and well-maintained reduce the hazard potential. Keep guards and shields in place on machinery and maintain equipment in good working condition. Store flammable liquids in approved containers; away form fire, flame, spark, pilot light, switches, arc-producing equipment and other ignition sources. Keep the workshop clean and well-lighted and provide adequate ventilation.

• Develop safe work habits: Unsafe actions cause

accidents with tools and machines. Be familiar with the equipment and know how to use them safely. Use the correct tool for the job and check its condition before starting. Comply with the warnings in this manual and take special precautions when working around electrical equipment. Do not work alone if possible and take no risks.

• Be prepared for an accident: Keep fire

extinguishers and safety equipment nearby. Agencies such as the Red Cross and public safety departments offer courses in first aid, CPR and fire control. Take advantage of this information to be ready to respond to an accident. Learn to be safety-conscious and make safety procedures part of the work routine.

TABLE 4-1 HAZARDS AND THEIR SOURCES

Fire and

Explosion

• Leaking or spilled fuel

• Hydrogen gas from battery

• Oily rag improperly stored

• Flammable liquids improperly

stored

Burns

• Hot exhaust pipes

• Hot engine and generator surfaces

Poisonous

Gas

• Operating genset where exhaust gases can accumulate

Electrical

Shock (AC)

• Improper generator connections

• Faulty wiring

• Working in damp conditions

• Jewelry touching electrical

components

Rotating

Machinery

• Fan guards not in place

Slippery

Surfaces

• Leaking or spilled oil

Heavy

Objects

• Removing genset form vehicle

• Removing heavy components

4-2-2 Special Tools

Engine

A complete set of standard and metric shop tools are required to service the engine.

Control and Generator

A complete set of standard and metric shop tools are required to service the control and generator. Also needed are:

 Lead or dead blow hammer  Battery hydrometer  Torque wrench  VOM millimeter  Frequency meter  Armature growler  Load bank  Jumper wires  Rotor Puller

SECTION 4. DISASSEMBLY AND SERVICE

- 20 -

4-3 Disassembly Chart

This chart is a quick-reference guide for disassembling the product. Be sure to follow the sequence shown here for better and safer work.

Example:To remove the frame. a) Remove the end cover. b) Remove the control box. c) Remove the fuel tank. d) Remove the muffler. e) Remove the frame.

GENERATOR DISASSEMBLY

FUEL TANK

MUFFLER

END COVER

CONTROL BOX

AVR

BRUSH

STATOR ROTOR

MOUNT RUBBER FRAME

ENGINE

REAR HOUSING

AIR CLEANER

CARBURATOR

RECOIL STARTER FAN COVER

FLYWHEEL STARTER MOTOR

SECTION 4. DISASSEMBLY AND SERVICE

- 21 -

4-4 Engine 4-4-1 Crankshaft / piston

a.DISASSEMBLY/ ASSEMBLY

REASSEMBLY: Install with the triangle mark toward the push rods.

DECOMPRESSOR WEIGHT

REASSEMBLY: Check that the decompressor weight moves smoothly, and the spring is not weak or worn.

REASSEMBLY: Install the tappets immediately before installing the camshaft.

REASSEMBLY: Push in until the bearing touches the crankcase. Be careful not to damage the oil seal.

REASSEMBLY: Install with the oil dipper toward the camshaft . The ribs on the cap and connecting rod must be aligned.

CRANKSHAFT

CONNECTING ROD CAP

OIL LEVER SWITCH

Crankshaft

VALVE LIFTER

PISTON

OIL ALERT UNIT

SECTION 4. DISASSEMBLY AND SERVICE

- 22 -

b.PISTON/ PISTON RING

MARKING

PISTON

PISTON PIN

REASSEMBLY: Install the connecting rod with the long end toward the triangle marked side of the

p

iston.

REASSEMBLY: Install by setting one end of the clip in the piston groove, holding the other end with long-nosed pliers, and rotating the clip in. Do not align the end gap of the clip with the cut-out in the piston pin bore.

PISTON PIN CLIP

REASSEMBLY:

1) Install all rings with the markings facing upward.

2) Be sure that the top (chrome plated) and second rings are not interchanged.

3) Check that the rings rotate smoothly after installation.

4) Space the piston ring end gaps 120 degrees apart, and do not align the gaps with the piston pin bore.

PISTON RING

TOP RING (CHROME PLATED)

OIL RING

SECOND RING

SECTION 4. DISASSEMBLY AND SERVICE

- 23 -

c.CAMSHAFT/ CRANKSHAFT

CRANKSHAFT

d.OIL LEVEL SWITCH

Ckeck continuity of the switch with an ohmmeter.

1) Hold the switch in its normal position. The ohmmeter should read zero resistance.

2) Hold the switch upside down. The ohmmeter should read infinity (∞) resistance.

3) Inspect the float by dipping the switch into a container of oil. The ohmmeter reading should go from zero to infinty as the switch is lowered.

REASSEMBLY: Align the index marks on the camshaft and timing gear.

CRANKSHAFT

CAMSHAFT

INDEX MARKS

(ON)

(OFF)

SECTION 4. DISASSEMBLY AND SERVICE

- 24 -

d.INSPECTION

CYLINDER ID(Inside Diameter)

Factory Specification Allowable limit

68.015 mm (2.6778 in)

68.165 mm (2.684 in)

PISTON SKIRT OD(Outside Diameter)

Factory Specification Allowable limit

67.985 mm (2.6766 in)

67.845 mm (2.6711 in)

PISTON-TO CYLINDER CLEARA NCE

Factory Specification Allowable limit

0.03-0.05 mm

(0.0012-0.002 in)

0.12 mm

(0.005 in)

PISTON RING SIDE CLEARANCE

Factory

Specification

Allowable limit

0.030-0.060 mm

(0.0012-0.0024 in)

0.15 mm

(0.006 in)

PISTON RING END GAP

Factory

Specification

Allowable limit

0.2-0.4 mm

(0.008-0.016 in)

1.0 mm

(0.04 in)

PISTON PIN OD

Factory

Specification

Allowable limit

17.998 mm (0.7086 in)

17.954 mm (0.7068 in)

SECTION 4. DISASSEMBLY AND SERVICE

- 25 -

PISTON PIN BORE ID

Factory

Specification

Allowable limit

18.002 mm (0.7087 in)

18.048 mm (0.7105 in)

PISTON-TO-PISTON PIN BORE CLEARANCE

Factory

Specification

Allowable limit

0.004.016 mm

(0.00016-0.0006 in)

0.08 mm

(0.0.003 in)

CONNECTING ROD SMALL END ID

Factory

Specification

Allowable limit

18.006 mm (0.7089 in)

18.07 mm (0.711 in)

CONNECTING ROD BIG END ID

Factory

Specification

Allowable limit

30.015 mm (1.1817 in)

30.066 mm (1.1837 in)

CRANKPIN OD

Factory

Specification

Allowable limit

29.985 mm (1.181 in)

29.92 mm (1.178 in)

CONNECTING ROD BIG END SIDE CLEARANCE

Factory

Specification

Allowable limit

0.1-0.7 mm

(0.0040.028 in)

1.1 mm

(0.043 in)

SECTION 4. DISASSEMBLY AND SERVICE

- 26 -

CAMSHAFT DIAMETER

Factory

Specification

Allowable limit

IN

27.7 mm (1.09in)

27.45 mm (1.081 in)

EX 27.75 mm

(1.093 in)

27.50mm (1.083 in)

CAMSHAFT CAM DIAMETER

Factory

Specification

Allowable limit

13.984 mm (0.5506 in)

13.916 mm (0.5479 in)

CAMSHAFT HOLDER ID

Factory

Specification

Allowable limit

14.00 mm (0.55 in)

16.048 mm (0.5531 in)

SECTION 4. DISASSEMBLY AND SERVICE

- 27 -

4-4-2 Flywheel

a.DISASSEMBLY/ ASSEMBLY

WOODRUFF KEY

REASSEMBLY: After installing the flywheel, check to be sure that the woodruff key is still in its slot on the crankshaft.

SPARK PLUG LEAD

REASSEMBLY: Check for cracked or damaged insulation; replace if necessary.

SPARK PLUG LEAD

REASSEMBLY: Clamp securely to the crankcase with the two clamps.

SECTION 4. DISASSEMBLY AND SERVICE

- 28 -

b. INSPECTION

AIR GAP (AT FLYWHEEL)

Measure the air gap between of the ignition and flywheel by thickness gauge.

A

ir gap

(at flywheel)

0.4±0.2 mm

(0.016±0.008 in)

IGNITION COIL RESISTANCE

1. Measure the resistance of the primary coil by attaching one ohm-meter lead to the ignition coil’s primary lead while touching the other test lead to the iron core.

2. Measure the resistance of the secondary side of the coil by removing the spark plug cap and touching one test lead to the spark plug lead wire while touching the other test lead to the iron core.

NOTE: A false reading will result if the spark plug

cap is not removed. If the resistance is not as specified, replace the

ignition coil.

SPARK PLUG CAP

Measure the resistance of the spark plug cap by attaching one ohm-meter.

If the resistance is not as specified, change the spark plug cap.

Spark Plug Cap 5K

Primary side resistance value 0.8-1.0 Ω

Secondary side resistance value 5.9-7.1 KΩ

0.4± 0.2 mm (0.016± 0.008 in)

IGNITION COIL

FLYWHEEL

SECTION 4. DISASSEMBLY AND SERVICE

- 29 -

4-4-3 Cylinder Head / Valves

a.DISASSEMBLY/ ASSEMBLY

CYLINDER HEAD GASKET

CYLINDER HEAD

CYLINDER HEAD BOLT

REASSEMBLY:

Before installation, remove carbon deposits from the combustion chamber and inspect the valve seats.

Measure the compression of the cylinder head after reassembly.

TORQUE:

26-28 N· m (260-280 kg· cm, 18.7-20.2 ft· lb)

REASSEMBLY/ DISASSEMBLY:

Tighten and untighten using a cross pattern.

CYLINDER HEAD COVER GASKET

CYLINDER HEAD COVER BOLT

CYLINDER HEAD COVER

CYLINDER HEAD COVER BOLT

TORQUE:

12-14 N· m (120-140 kg· cm, 8.7-17.4 ft· lb)

REASSEMBLY/ DISASSEMBLY:

Tighten and untighen using a cross pattern.

SECTION 4. DISASSEMBLY AND SERVICE

- 30 -

EXHAUST VALVE

SPARK PLUG

ROCKER ARM

VALVE ROTATOR

REASSEMBLY:

Do not interchange with the exhaust valve.

VALVE HEAD DIAMETER:

IN: 24 mm

(0.94 in)

EX: 22 mm

(0.87 in)

REASSEMBLY:

Before installation, remove carbon deposits and inspect the valve.

INTAKE VALVE

DISASSEMBLY:

Compress the value spring and slide the retainer out to the side, so the valve stem slips through the hole at the side of the retainer.

Do not remove the valve spring

retainers while the cylinder head is installed, or the valves will drop into the cylinder.

REASSEMBLY:

If the valve rotator is not installed, the valve may drop into the cylinder when starting the engine.

REASSEMBLY:

Check both ends for wear and check the rod for straightness.

Be sure the rod ends are firmly seated in the lifter.

PUSH ROD

REASSEMBLY:

Check the pivot bolt, push rod and rocker arm before installing.

REASSEMBLY:

Before installation, clean and adjust the spark plug.

SECTION 4. DISASSEMBLY AND SERVICE

- 31 -

b.INSPECTION

CYLINDER HEAD

Remove carbon deposits from the combustion chamber. Clean off any gasket material from the cylinder head surface.

Check the spark plug hole and valve areas for cracks.

Check the cylinder head for warpage with a straight edge and a feeler gauge.

VALVE SEAT WIDTH

Measure the valve seat width.

If the valve seat width is under the factory section,

or over the service limit, recondition the valve seat.

VALVE GUIDE ID NOTE: Ream the valve guides to remove any

carbon deposits before measuring. Measure and record each valve guide I. D.

Factory Specification Allowable limit

5.50 mm (0.217 in) 5.572 mm (0.2193 in)

Replace the cylinder header if they are over the allowable limit.

GUIDE TO STEM CLEARANCE

Subtract each valve stem O.D. from the corresponding guide I.D. to the stem to guide clearance.

Factory

Specification

Allowable limit

IN

0.02-0.044 mm

(0.0008-0.0016 in)

0.10 mm

(0.004 in)

EX

0.06-0.087 mm

(0.0002-0.0034 in)

0.12 mm

(0.005 in)

If the stem to guide clearance exceeds the Allowable limit, determine if the new guide with standard dimensions would bring the clearance within tolerance. If so, replace any guide as necessary and ream to fit. If the stem to guide clearance exceeds the allowable limit with new guides, replace the valves as well.

NOTE: Recondition the valve seats whenever the

valve guides are replaced.

Allowable limit 0.1 mm (0.004 in)

Factory

Specification

Allowable limit

0.8 mm (0.03 in) 2.0 mm (0.08 in)

STRAIGHT EDGE

FEELER GAUGE

SECTION 4. DISASSEMBLY AND SERVICE

- 32 -

VALVE STEM OD

Inspect each valve for face irregularities, bending or abnormal stem wear. Replace the valve if necessary. Measure and record each valve stem O.D.

Factory

Specification

Allowable limit

IN

5.48 mm (0.216 in)

5.318 mm

(0.2093 in)

EX

5.44 mm (0.214 in)

5.275 mm

(0.2077 in)

Replace the valves if their O.D. is smaller than the allowable limit.

VALVE SPRING FREE LENGTH

Measure the free length of the valve springs.

Replace the springs if they are shorter than the allowable limit.

Factory

Specification

Allowable limit

30.0 mm (1.18 in) 28.5 mm (1.122 in)

SECTION 4. DISASSEMBLY AND SERVICE

- 33 -

4-4-4 Recoil Starter / Fan Cover

a.DISASSEMBLY/ ASSEMBLY

FLANGE NUT 16mm

REASSEMBLY:

Install by aligning the three lugs on the rear side of the fan with the small hole in the flywheel.

When disassembling and assembling, take care not to damage the fan blades.

COOLING FAN

RECOIL ST A RTER ASSY

REASSEMBLY:

Install with the starter grip position as shown.

DISASSEMBLY/ REASSEMBLY:

Remove and install with the recoil starter ASSY.

FAN COVER

DISASSEMBLY/ REASSEMBLY:

Hold the flywheel by placing a screwdriver into the pulley.

STARTER PULLEY

REASSEMBLY:

Install by aligning the hole in the pulley with the lug on the cooling fan.

SECTION 4. DISASSEMBLY AND SERVICE

- 34 -

b.DISASSEMBLY (RECOIL STARTER ASSY)

The recoil starter can cause personal injury, Wear safety glasses. Do not let the recoil spring

snap.

ST ARTER ROE

REASSEMBLY:

Install with the starter grip position as shown.

REEL COVER

REASSEMBLY:

Align the ratchet with the reel cover notch.

REASSEMBLY:

Install on the starter case after installing the return spring.

STA RTER REEL

REASSEMBLY:

Check for wear or damage.

Note the installation direction.

RATCHET

REASSEMBLY:

Hook the outer hook in the groove of the starter reel and inner hook on the starter case tab.

RETURN SPRING

SECTION 4. DISASSEMBLY AND SERVICE

- 35 -

c.RECOIL STARTER ASSEMBLY

Wear gloves and eye wear to protect

your hands and eyes.

Do not let the return spring jump.

a) Hook the spring outer hook in the reel groove,

and install the reel on the starter case, so that the spring inner hook is hooked to the starter case tab by turning the reel counterclockwise.

b) Feed the end of the rope through the hole in

the starter reel, and tie the rope end. Wind the rope onto the direction shown, and wedge the rope end in the notch on the edge of the reel.

c) With a short length of the rope extending from

the starter reel notch, pull the end of the rope out of the case, feed it through the starter grip, and tie a knot in the end of the rope.

d) Install the friction plates, friction spring, ratchet

pin, guide plate, and reel cover. Tighten the reel cover bolt.

e) Rotate the reel three full turns in the direction of

the arrow.

f) Check the operation of the ratchet by pulling

the starter rope out several times.

SECTION 4. DISASSEMBLY AND SERVICE

- 36 -

4-4-5 Air Cleaner

DISASSEMBLLY/ REASSEMBLY

BREAT HER TUBE

AIR CLEANER GASKET

REASSEMBLY:

Make sure the gasket is not damaged, broken or bent. Install correctly as shown.

AIR CLEANER COVER

REASSEMBLY:

Make sure to seat the gasket in the groove on the edge of the case all the way around properly.

REASSEMBLY:

Connect between the air cleaner case and tappet cover.

ELEMENT

SEP ARATOR

SEAL

AIR CLEANER CAS E

SECTION 4. DISASSEMBLY AND SERVICE

- 37 -

4-4-6 Carburetor

DISASSEMBLLY/ REASSEMBLY

Gasoline is flammable and explosive. Close the fuel shut off valve, and drain the carburetor

before servicing the carburetor.

CARBURETOR BODY

REASSEMBLY:

Clean internal passages and orifices with compressed air before installing.

REASSEMBLY:

Check for correct installation.

O-RING

REASSEMBLY:

Check for smooth movement after installing.

FLOAT

REASSEMBLY:

Clean thoroughly with

compressed air before

installation.

MAIN NOZZLE

MAIN JET

REASSEMBLY:

Clean thoroughly with

compressed air before

installation.

FLOAT VALVE

REASSEMBLY:

Check for worn valve or weak spring before installation.

REASSEMBLY:

Check the screw head for wear or damage before installing. INITIAL OPENING: 1-5/8 turns out.

PILOT SCREW

REASSEMBLY:

After assembly, check for any sign of fuel leakage.

SET BOLT

DRAIN SCREW

REASSEMBLY:

Clean thoroughly with compressed air and check for leaks after installation.

SECTION 4. DISASSEMBLY AND SERVICE

- 38 -

4-5 Generator 4-5-1 Fuel Tank

DISASSEMBLLY/ REASSEMBLY

Gasoline is flammable and explosive. Drain the fuel tank and fuel line before disassembly.

Wipe up spilled fuel immediately.

REASSEMBLY:

After reassembly, check the operation of the float.

FUEL METER

REASSEMBLY:

Make sure the passages are not clogged.

Check for fuel leakage after installation.

FUEL VALVE

REASSEMBLY:

Wash to remove sediment. and dry thoroughly before installation.

SEDIMENT CUP

REASSEMBLY:

Make sure that the air vent hole is clean and unclogged. Blow with compressed air if necessary.

FUEL TANK CAP

REASSEMBLY:

Check to be sure the strainer is clean and undamaged before installation.

FUEL STRAINER

REASSEMBLY:

Wash the tank to

FUEL TANK

REASSEMBLY:

Check to be sure the filter is clean and undamaged.

FUEL FILTER

SECTION 4. DISASSEMBLY AND SERVICE

- 39 -

4-5-2 Muffler

DISASSEMBLLY/ REASSEMBLY

EXHAUST PIPE

REASSEMBLY:

Install after removing the carbon deposits from the muffler using a plastic hammer.

MUFFLER

REASSEMBLY:

Install after removing the carbon deposits from the exhaust pipe.

EXHAUST PIPE

REASSEMBLY:

Attach after removing the carbon from the screen with a wire brush.

SECTION 4. DISASSEMBLY AND SERVICE

- 40 -

4-5-3 Generator

a. DISASSEMBLLY/ REASSEMBLY

GENERAT OR ASSY

CRANKCASE GROMMET

REASSEMBLY:

Wipe dirt or oil off the tapered portion of the rotor and crankshaft before installing.

REASSEMBLY:

Check to be sure the grommet

REASSEMBLY:

43-47 N·m (430-470 kg·cm,

31.0-33.9 ft·lb)

ROTOR BOLT

DISASSEMBLY:

Remove the brush holder

BRUSH HOLDER ASSY

REASSEMBLY:

Tighten in crisscross pattern in 2-3 steps.

After tightening, make sure there is no clearance between the crankcase cover and stator cover.

8-12 N·m (80-120 kg·cm,

5.8-8.7 ft·lb)

STATOR BOLT

REASSEMBLY:

Insert the alignment tabs onto the holes.

Make sure the rubber is not chipped, hard or worn.

Note the installation direction.

RUBBER MOUNT

SECTION 4. DISASSEMBLY AND SERVICE

- 41 -

REAR HOUSING

ROTOR

DISASSEMBLY:

Install the appropriate rotor puller (special tool), hold the flywheel and torque the puller to 6.9 Kg-cm (50 ft-lb).

To avoid damaging the rotor, place a wooden

block and a shop rag under the rotor for support.

NOTE:

If torquing the rotor puller does not free the rotor from the crankshaft, tap the end of the puller with a brass hammer to help loosen the rotor.

To prevent eye injury, always wear safety

glasses or goggles when striking the end of the rotor puller.

STATOR

STATOR COVER

GENERA TOR COOLING FAN

GENERATOR END COVER

AC OUTPUT TERMINAL

AV R ASSY

BRUSH HOLDER ASSY REAR HOUSING

SECTION 4. DISASSEMBLY AND SERVICE

- 42 -

b. INSPECTION

CARBON BRUSH/ SLIP RING

Remove the carbon brushes from the brush holder.

Check the brush for length, wearing condition or any other defect. Replace if the length is less than 5 mm (0.20in).

NOTE:

z Connect the Blue wire lead to the positive (+)

side of the brush holder.

z Avoid damaging the brushes when removing

and installing the brush holder.

Visually inspect the slip rings for dust, rust or other damage. If necessary, wipe them with a clean lint-free cloth. If they are rusted or damaged, remove the rotor and rub with fine emery cloth.

FIELD WINDING

Remove the brushes and measure resistance between the slip rings.

If the specified resistance is obtained at the slip rings, but not at the brush terminals, clean or replace the brushes.

If the specified resistance is not obtained at the slip rings, clean or replace the rotor.

2400 40-50 Ω

RESISTANCE

2500 35-45 Ω

SECTION 4. DISASSEMBLY AND SERVICE

- 43 -

MAIN WINDING

Using an ohmmeter, measure the resistance between the AC output terminals.

NOTE:

Set the voltage selector switch to 120 V only position.

If the resistance is zero or infinity, replace the stator.

EXCITER WINDING

Using an ohmmeter, measure the resistance between the Light green/ Red and Green wires in the 4P coupler.

If the resistance is zero or infinity, replace the stator.

DC WINDING

Using an ohmmeter, measure the resistance between the brown wire leads at the DC diode connecter.

If the resistance is out of specification, replace the stator.

2400 0.51-0.53 Ω

3500（Ⅰ）

0.76-0.79 Ω

RESISTANCE

3500（Ⅱ）

0.76-0.79Ω

2400 3.1-3.3 Ω

3500 1..5-1.7 Ω

RESISTANCE

Slip ring -

Ground

∝

RESISTANCE 0.4-0.6 Ω

Br W R Bu

AC OUTPUT TERMINALS

3500

Br (Ⅰ) W

R

(Ⅱ)

Bu

2400

AC OUTPUT TERMINALS

Br

W

Br

W

SECTION 4. DISASSEMBLY AND SERVICE

- 44 -

4-5-4 Control Panel

a. DISASSEMBLLY/ REASSEMBLY

GENERATOR END COVER

CONTROL PANEL

SECTION 4. DISASSEMBLY AND SERVICE

- 45 -

2400

PANEL END COVE R

VOLTMETER

AC BREAKER

RESET SWITCHES

DC BREAKER

RESET SWITCH

ON/STOP

SWITCH

12 Volt DC

Terminals

PANEL FRONT COVER

EARTH

GROUND

LUG

GFCI

SECTION 4. DISASSEMBLY AND SERVICE

- 46 -

3500

P ANEL END COVER

FUSE AND FUSE COVER

VOLTAGE SELECTOR WITCH

VOLTMETE R

AC BREAKER

RESET SWITCH

AC BREAKER

RESET SWITCHES

DC BREAKER

RESET SWITCH

START/ON/STOP

SWITCH

AC RECEPTACLE

(120/240VAC)

12 Volt DC

Terminals

PANEL FRONT COVER

EARTH

GROUND

LUG

GFCI

SECTION 4. DISASSEMBLY AND SERVICE

- 47 -

2400

EXCITER WINDING 4P COUPLER

1) Red (+)

2) Blue (-)

Blue (+

)

GROUND CABLE

AC OUTPUT

TERMINAL STRIP

3) Blue

4) Green

5) White

DC DIODE 4P COUPLER

AVR

Yellow (-)

Brown

White

Brown

White

SECTION 4. DISASSEMBLY AND SERVICE

- 48 -

3500

GROUND CABLE

Brown

White

Red

Blue

AC OUTPUT

TERMINAL STRIP

DC DIODE 4P COUPLER

AVR

Brown

White

Red

Blue

Yellow (-)

Blue (+)

Main Winding(Ⅰ)

Main Winding(Ⅱ)

1) Red (+)

2) Blue (-)

EXCITER WINDING 4P COUPLER

3) Blue

4) Green

5) White

SECTION 4. DISASSEMBLY AND SERVICE

- 49 -

b. INSPECTION ENGINE SWITCH

Check for continuity between the terminals with the

switch in each position.

Yello w/

Black

Green/

White

Green/

White

Red White

Wire

Position

IG E FS G

L L

OFF

ON

When switch to “OFF” position, IG is connecting to E. When switch to “ON” position, L is connecting to L.

DC BREAKER RESET SWITCH

Check continuity between the breaker terminals.

There should be continuity with the breaker button pushed in.

AC BREAKER RESET SWITCHES

Check continuity between the breaker terminals. There should be continuity with the breaker button pushed in.

VOLTMETER

Using an ohmmeter, check for continuity between the terminals.

Continuity should exist between them.

AC RECEPTACLE

Connect the terminals of the receptacles with a piece of wire.

Using an ohmmeter, check for continuity between the terminals.

If there is no continuity, the receptacle is defective, and must be replaced.

E L

BAT

L

FS

IG

G

ST

SECTION 5. WIRING DIAGRAMS

- 50 -

5-1 The Wiring Diagram of 2400

0

3 0 0

1 0 0

2 0 0

V

~

+

-

EIG

OFF

ON

Br

YLgBl

W

G

R

Bu

Light green

Brown

Yellow

Black

White

Green

Red

Blue

SECTION 5. WIRING DIAGRAMS

- 51 -

5-2 The Wiring Diagram of 3500

+

-

EIG

OFF

ON

Br

YLgBl

W

G

R

Bu

Light green

Brown

Yellow

Black

White

Green

Red

Blue

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