Onan MicroLite 2800 Service Manual

w

MicroLite'"

2800

Series

Printed in

U.S.A.

981

-0506

3-91

(Spec

A

&

B)

Safety

Precautions

Before operating tho generator

set,

read

the

Operator's

Manual and become familiar with it and the ui ment.

Safe

proper1 operatad and malntalned. Many accidents are

The

following symbols. found throughout this manual, alert you

to potentiall dangerousconditions to the operator, service per-

and etnclent opontlon can

be

achieved on

77

y

f

the

unlt

Is

caused

?I

y

failure to follow fundamental rules and precautions.

sonnel. or

t

x

e equipment.

Thls

symbol

warns

of

lmmedlate

haz-

anis

whlch

wlll

result

In seven?

personal

lnjuty

or

death.

A+W-AFINING~

Thls symbol

refers

to

a

hazard

or

unsafe

practlce

whlch can result

In

severe personal

lnjqf

or death.

&CAUTION?

-

_.__

Thls

symbol

refers

to a hazard

or

unsafe

-

.

practice which

can

result In personal InjuIy or prod-

uct or property damage.

FUEL AND FUMES ARE FLAMMABLE.

Fire,

explosion,

and

personal injury

can

resutt from improper practices.

DO

NOT fill

fuel

tanks while engine is running. Fuel contact

with

hot

engine

of

exhaust is a potential fire hazard.

DO

NOT SMOKE

OR

USE AN

OPEN

FLAME nearthe gen-

orator set or fuel

thank

Fuel lines must be adequately secured and free of leaks. Fuel connection at

the

engine should be made with

an

ap-

proved flexible,

nor~~nductive

line.

Do

not

use

copper

pip-

ing

on

flexible lines

as

copper will work harden and

become

bnttle.

Be

sure all fuel supplies have a

positive

shutoff valve.

GASOLINE AND

LPG

FUEL MAY BE ACCIDENTAUY

IG

NmED BY ELECTRICALSPARKS,

rumntlngthr huardof

Jury

or

death.

Whon lnrtalllng tho generator

set:

fln

or

explosion,

whkh

an

rosu

P

t

In

savere pond

In-

Do

not

tie

electrical

wiring

to fuel

lines.

Do

not

run

electrical

lines

and

fuel lines through

the

same

compartment openings. Keep

electrical

and

fuel lines

as

far

apart

as

possible.

Place a physical barrier between fuel lines

and

electrical

lines

wherever

possible.

If

electrical

and

fuel

lines

must

pass

through the same

com-

partment opening,

make

certain that they are physically

ssparated

by

ruming them thrwgh

individual

channels,

or

by passing each line

through

a separate piece of

tubing.

DO

NOT

SMOKE

while

servicing

batteries.

Lead acid

bat-

teries emit a highly explosive hydrogen gas that

can

be

ig-

nited

by eiectricai

arcing

or by smoking.

EXHAUST

GASES

ARE

DEADLY

0

Never sleep

in

the

vehicle with the generator set running

un-

less

vehicle

is

equipped

with

an operating

carbon

monoxide

detector.

Provide

an

adequate exhaust system

to

properly

expel

dis-

charged gases.

Inspect

exhaust system daily for leaks per the maintenance schedule. Ensure that exhaust manifokls are secure

and

not warped.

Do

not

use

exhaust gases to

heat a compartment.

Be

sure

the

unit

is

well

ventilated.

MOVING

PARTS

CAN CAUSE SEVERE PERSONAL

IN-

JURY

OR

DEATH

Before starting work on

the

generator set. disconnect batter-

ies.

This

will prevent accidental arcing.

Keep your hands away from moving parts.

0

Make sure that fasteners

on

the generator set are secure. Tighten supports and clamps. keep guards in position over fans, drive belts, etc.

0

Do

not wear loose clothing or jewelry while working on generator sets. Loose clothing and jewelry can become caught in moving parts. Jewelry can

short

out electrical contacts

and

cause

shock or burning.

0

If

adjustment must be made while the unit is running,

use

ex-

treme caution around hot manifolds, moving parts, etc.

ELECTRICAL SHOCK CAN CAUSE SEVERE PERSONAL INJURY

OR

DEATH

I

Disconnect starting battery before removing protective

shields

or touching electrical equipment. Use rubber insula-

tive

mats placed on dry wood platforms over

floors

that are

metal or concrete when

around

electrical

equipment.

Do

not

wear darnpclothing (particularlywet

shoes)

orallawskin sur-

faces to

be

damp when handling electrical equipment.

Use extreme caution when working on electrical compo-

nents. High voltages can cause

injury

or death.

FoUowall

state

and

local

electrical

codes.

Have all electrical installations performed by a qualified licensed electrician. Tag open switches to avoid accidental closure.

DO

NOT CONNECT GENERATOR

SE3

DIRECTLY

TO

ages

can

flow

from

the

generator set into the

utility

line.

This

croates a potential for

electrocution

or

property damage.

Connect onlythrough an approved

device

and

after building

main switch is open. Consult

an

electriaan

in

regard to

emergency power

use.

ANY

BUILDING ELECTRICAL SYSTEM. Hazardous volt-

GENERAL

SAFETY

PRECALmONS

Have afire extinguisher nearby. Maintain extinguisher prop-

erly

and

become familiar

with

its

use.

Extinguishers

rated

ABC

by

the

NFPA are appropriate for all applications. Con-

dt

the

local

fire department

for

the

meet

type

of extin-

guisher

for

various

applications.

Hot

codants

under pressure

can

cause

severe

personal

in-

jury.

DO

NOTopen a radiator pressure cap

whii

th4

engine

b

running.

Stop

the

engine and carefully

Meed

the system

-e-

Benzene

and lead. fwnd

in

some

gasdine,

have

been

iden-

tified

by

some

state

and

federal

agencies

as

causing

cancer

orreproductive toxicity. When checking, draining or adding gasoline.

take

care

not

to

ingest,

breathe

the

fumes,

or

con-

tact

gasdine.

Used

engine oils have been identified by some

state

or

fed-

eral

agencies

as

causing cancer or reproductive toxicity.

When chec#ng or changing engine oil.

take

care not to

in-

gest,

breathe the fumes. or

contact

used

oil.

Remove all unnecessary grease

and

oil from the

unit.

Accu-

mulated grease

and

oil can cause overheating and engine

damage, which presents a potential fire

hazard.

DO

NOTstore anything in

the

generator compartment

such

as

oil or gas cans, oily rags, chains, wooden blocks, portable

propane

cylinders, etc. A fire could resuH

or

the

generatoi

set operation

(cooling,

noise

and

vibration)

may

be

ad.

versely affected.

Keep

the compartment floor clean and dry.

Do

not

work on this equipment when mentally or physically fatigued, or after consuming any alcohol or drugthat makes the operation

of

equipment unsafe.

RV-8

Table

of

Contents

SECTION

1

.

2

.

3

.

4

.

5

.

6

.

7

.

8

.

9

.

TITLE

PAGE

SAFETY PRECAUTIONS

..........................

Inside Front Cover

INTRODUCTION

............................................

1-1

About this Manual

.........................................

1-1

Model Identification

........................................

1-1

SPECIFICATIONS

...........................................

2-1

DIMENSIONS AND CLEARANCES

...............................

3-1

TORQUE SPECIFICATIONS

...................................

4-1

PREPARING

TO

SERVICE

.....................................

5-1

Troubleshooting

...........................................

5-1

SpecialTools

.............................................

5-1

Safety Considerations

.......................................

5-1

Set Removal

..............................................

5-2

ENGINE-PRIMARY SYSTEMS

..................................

6-1

Introduction

..............................................

6-1

Troubleshooting Engine Primary Systems

........................

6-1

Exhaust System

...........................................

6-5

Cooling System

...........................................

6-8

ignition System

............................................

6-8

Crankcase Ventilation System

................................

6-10

Governor

...............................................

6-10

Gasoline Fuel System

......................................

6-11

LPG Fuel System

.........................................

6-18

Electric Starter

...........................................

6-21

CONTROL

.................................................

7-1

Introduction

..............................................

7-1

Control Description

........................................

7-1

Control Operation

-

Gasoline Fueled

............................

7-1

Control Operation

-

LPG Fueled

...............................

7-3

Control Troubleshooting

.....................................

7-6

GENERATOR

...............................................

8-1

Introduction

..............................................

8-1

Generator Description

......................................

8-1

Generator Operation

........................................

8-2

Generator Troubleshooting

...................................

8-2

Generator Service

.........................................

8-8

Brushes and Slip Rings

.....................................

8-10

Voltage Regulator (VR1) Test

................................

8-11

Generator Testing

.........................................

8-11

Rotor

Bearing Replacement

.................................

8-15

ENGINE-BLOCK ASSEMBLY

..................................

-9-1

introduction

..............................................

9-1

Oil

Pan and Oil Level Switch

..................................

9-1

Head Cover

..............................................

9-2

Cylinder Head

............................................

9-2

Valve System

.............................................

9-2

Crankcase Cover

..........................................

9-5

Camshaft and Tappet Removal

................................

9-5

Governor

................................................

9-6

Piston Assembly Removal and Service

..........................

9-6

Crankshaft

..............................................

9-10

Cylinder Block

...........................................

9-10

Timing Gears

............................................

9-12

Bearings

...............................................

9-12

OilSeal

................................................

9-12

Table

of

Contents

SECTION

TITLE

PAGE

10 .

SERVICE

CHECKLIST

...........................................................

10-1

General

.........................................................................

10-1

Mounting

.......................................................................

10-1

Lubrication

.....................................................................

10-1

Wiring

..........................................................................

10-1

Initial Start Adjustments

........................................................

10-1

Output Checks

.................................................................

10-1

Exhaust System

................................................................

10-1

Fuel System

....................................................................

10-2

Control

.........................................................................

10-2

Mechanical

.....................................................................

10-2

ii

Section

1

Introduction

I

ABOUT THIS MANUAL

This manual provides service information for the Onan

KV

generator set.

It

is intended for the experienced serviceperson. This manual covers troubleshooting, disassembly, repair, reassembly, and adjustments for the engine, generator, and control. The serviceperson should be thoroughly familiar with the principles of gasoline engine operation and have a basic knowledge

of

electrical fundamentals. Other Onan publications such as Electrical/Mechanical Fundamentals (932-0408), Onan Generator Training Manual (932-0404), and

KV

Operator’s Manual

(981

-01

29) and Installation Manual

(981

-0626) are recommended as additional sources of

information.

I

MODEL IDENTIFICATION

When contacting an Onan dealer or distributor, always supply the complete Model number and Serial number as shown on the Onan nameplate. This information is necessary to identify the set when ordering replacement parts. See Figure

1.

Always use genuine Onan replacement parts obtained from an authorized Onan dealer or distributor. Universal replacement type parts (usually intended for automotive use) often look similar but do not Derform to Onan specifications. Only genuine Onan ieptacement designed and tested for the application.

parts are

Read all service procedures completely before beginning any repair work and observe all cautions and warnings. It is extremely important that the generator set installation maintain compliance with the applicable codes and standards for

RV

installations (see Installation Manual). The most critical areas of concern include the exhaust system, fuel system, electrical wiring, compartment construction, and ventilation system. Improper service can create an unsafe installation that can result in damage

to

the vehicle and equipment and can cause

severe personal injury or death to the user.

l

AWARNING

I

H

Serial

NO.

I

PF

Amps

Hz

FIGURE

1.

ONAN NAMEPLATE

INCORRECTSERVICE

OR

REPLACEMENT OF PARTS CAN RESULTIN SEVERE PERSONAL INJURY, DEATH, AND/OR EQUIPMENT DAMAGE. SERVICE PERSONNEL MUSTBE QUALIFIED TO PERFORM ELECTRICAL AND/OR MECHANICAL SERVICE.

1-1

.

Section

2.

Specifications

GENERAL

.

Engine Design.

...............................................

4-Cycle, Single Cylinder, Overhead Valve

Generator Design

..........................................

Onan, Revolving Field, 2-Pole, Brushless AC

Starting System

...............................................................

.12-V0lt Electric Starter

Engine Speed

............................................

.60

Hertz

.

3600

r/min,

50

Hertz

-

3000

r/min

Weight..

..............................................................................

110

Ib

(50

kg)

\

ENGINE

DETAILS

Displacement..

......................................................................

12 ins (197 cm3)

Compression Ratio..

...........................................................................

8.51

Bore..

..............................................................................

.2.64 in

(67

mm)

Stroke

...............................................................................

.2.2 in (56 mm)

Oil Capacity..

.........................................................................

1.0

qt

(0.95

L)

Ventilation (Free Area).

.............................................................

.24

in2 (154.8 cm2)

Fuel

.........................................................................

Gasoline/Gasohol/LPG

TUNE-UP SPECS

Spark Plug Gap..

..................................................................

0.025 in (0.64 mm)

Timing..

..................................................................................

.25" BTC

Valve

Lash

(Intake and Exhaust)

.....................................................

0.002

in

(0.05

mm)

GENERATOR DETAILS

Gasoline Models

....

1.7 KV 2.0 KV 2.2 KV 2.8 KV

Power (Watts)

.......

1700 2000

2200 2800

Voltage

.............

240

220

120 120

Amps..

.............

7.1

9.1 18.3 23.3

Frequency (Hertz)

...

50 50

60 60

Phase

..............

10

10 10

Wires

..............

2

Battery Charge..

....

1

Amp

1

Amp

1

Amp

1

Amp

LPG

Models

........

Power (Watts)

.......

Voltage

.............

Amps.

..............

Frequency (Hertz)

.

,

Phase

..............

Wires

..............

Battery Charge

......

2.0 KV 2000 220

9.1

50

10

2

1

Amp

2.5 KV 2500 120

20.8 60

10

2

1

Amp

2-1

ITEM

CYLINDER HEAD

Cylinder Head Deformation Limit

Section

3.

Dimensions

and

Clearances

INCHES MILLIMETERS

0.00394/3.39370 0.1001100.0

Allowable Limit

Intake

Exhaust

Valve Clearance

Torque

I

(18-24 ftolb) (25-33 Nom)

0.0039

0.1

0

0.00079-0.0031 0.02-0.080

Intake 44.5"-45'

44.5" -45"

VALVE

Valve Face Angle

0.0591 1.5

0.2153-0.21 57 5.468-5.480

Exhaust 0.2142-0.21 50 5.440-5.460

Valve Stem Diameter

Valve Guide Inside Diameter

I

0.21 65-0.21

70

5.500-5.51 2

Valve and Guide Stem

Clearance Between

Reference Valve

Intake 0.00079-0.001 73 0.020-0.044

0.001

57-0.00283 0.040-0.072

Intake

Opening

Valve Opening Closing

Closing Timing

(when cool) Exhaust

Opening

Closing

78' (58'-70' before top dead center)

118' (98"-110° after bottom dead center)

118' (98'-110°after bottom dead center)

78" (58"-70' before

top

dead center)

Reference Value 1.299-1.31 9 33.0-33.5

i

Allowable Limit 1.287 32.7

Valve

Spring

Free Height

Reference Value 12.94

Ibf

0.8858 in 5.87

kgff

22.5 m

11.64 lb/0.8858 in 5.28 kgfl22.5 m

Load and Height

0.0591 1.5

I

Allowable Squareness Limit

Valve Seat

Intake

Exhaust

Valve Seat Angle

45" 45"

Reference Valve

I

0.0394-0.051

2

1.0-1.3

3-1

Section

3.

Dimensions and Clearances - Continued

ITEM

Valve Lifter

Outer Diameter

Reference Value Clearance Between Valve Lifter Allowable Limit And Guide

Camshaft

Standard Journal Diameter

Clearance Between Camshaft

Journal Bearing (Flywheel Side)

Intake

Value Exhaust

Intake

Limit Exhaust

Reference

Cam Height

Allowable

Allowable Side Clearance Limit

Bending Limit

Timing Gear

Backlash

Reference Value

Allowable Limit

Reference Value

Allowable Limit

Cylinder Inner Diameter

Minimum Clearance Between Cylinder and Piston

Piston

Outer Diameter (Skirt Diameter)

Piston

Ring

Reference Value

Allowable Limit

Gap

Clearance Reference Limit Between Ring And Ring Allowable Limit Groove

INCHES MILLIMETERS

-:

0.001

4-0.0030 0.035-0.075

I

0.0039 0.1

0.5892-0.5899 14.966-1 4.984

0.0006-0.0020

0.01

6-0.052

0.9705 24.65

1

0.9665 24.55

0.0079

0.0020

0.0036-0.0056 0.092-0.1 41

0.0079

2.6378-2.6386 67.00-67.02

0.0039

0.1

0

I

0.001

6

0.04

2.6354-2.6362 66.94-66.96

0.0079-0.01 57 0.20-0.40

0.0354

0.90

I

0.0008-0.0024 0.02-0.06

I

0.0039

0.1

0

.

3-2

Section

3.

Dimensions and Clearances - Continued

Clearance Reference Value between small end

And Piston Pin Allowable Limit

Bending Limit Torsion Limit Bolt Tightening Torque

Connecting Rod

ITEM

0.0004-0.001

0

0.01

0-0.025

0.0039

0.1

0

0.001

6 0.04

0.001

6 0.04

(10.1-14.5 ftolb)

(1

3.7-1 9.6 Nom)

INCHES MILLIMETERS

Crankshaft

Reference Value

Pin Diameter

Wear Limit

Reference Value Crank pin oil Clearance Allowable Limit

Piston Pin Outer Diameter

I

0.5906-0.5907

1

5.000-1

5.005

1.1798-1.1804 29.967-29.982

1.1

780 29.92

0.0007

-

0.002 1

0.01

8-0.054

0.0039 0.1

0

Connecting Rod

(Small

End)

Inner Diameter Reference Value

Bending Limit

Reference Value

Allowable Limit

Axial Play

1

0.591 1-0.591

5

0.0008 0.02

0-0.0039

0-0.1

0

0.0079 0.20

15.01 5-1

5.025

Reference Value

I

0.9835-0.9840

24.980-24.993

0.9803 24.9

Journal Dia.

~~ ~ ~

Reference Value

0.0008-0.0039 0.02-0.1

0

Allowable Limit 0.0079

0.20

Side Clearance

Ignition Plug Standard Gap

I

0.0236-0.0276

0.6-0.7

3-3

Section

4.

Torque

Specifications

TORQUE

SPECIFICATIONS

FOOT-POUNDS NEWTON-METERS

Connecting Rod Head Cover

10-14 14-20

3.3-6

4.4-8

Generator Housing

to

Engine Mounting Nuts

Cylinder Head (Cold) Endbell

to

Stator

Housing Mounting Screws Engine Cooling Shrouds Fan Mounting Screws

Gearcase Cover

6-7 8-9

18-24 25-33

6-9 8-1

2

6-9 8-1 2 6-9 8-1 2

11-14 14-19

Intake Manifold

8-1

5

11

-20

I

Carburetor Mounting Nut

6-8 7-1

1

Muffler Bkt to Engine

5-9

7-12

I

Muffler Flange to Engine

10-1

4 14-20

____

~~

Oil Base and Generator

Housing to Mounting Stud

Oil

Base to Engine

22-27

6-9 8-1 2

30-37

Oil Drain Plug Oil Watch bolt

Rotor Through-bolt Spark Plug Starter Bkt.

to

Engine

18-24 25-33

6-9 8-12

40-50 54-68

8-1 8 10-24

6-9 8-1

3

Speed Adjust Lever Nut Vibration Isolators

Starter Bkt. to Starter

8-1

5

11

-20

4-6 5.5-8.0

2.5-3.3 3.4-4.5

~~

Starter Flange to

Endbell Mounting Screws

16-24 22-33

~~ ~

Governor Lever Nut

6-8

7-1

1

4-1

Section

5.

Preparing

to

Service

TROUBLESHOOTING

.

Before starting

to

service the generator set, follow a

systematic troubleshooting procedure to locate and iso-

late the problem. For servicing purposes, the generator

set can be divided into the following:

0

Engine - Primary Systems

0

Control

0

Generator Engine - Block Assembly

This manual contains separate sections that cover each area.

Several troubleshooting guides are included in this manual to help the serviceperson locate the cause of various malfunctions. Note that some malfunctions might have several possible causes. Forthis reason, the serviceperson may have to investigate several likely problem areas in order to isolate the source of the malfunction. Because of the complexity of the product, a troubleshooting chart cannot list every malfunction and the cause. In some situations, the serviceperson will have

to

rely on experience and a knowledge of the

product

to

locate the problem and service as required.

SPECIAL

TOOLS

The following special tools may be required

to

service

the generator set. Some

of

these

tools

may be purchased from Onan whileothers may be purchased from outside suppliers.

A

complete listing of the tools availa-

ble from Onan is contained in the Tool Catalog

(900-

0019)

which is available from Onan Dealers or

Distributors. Engine

Tools

Torque wrench

(0-50

Ft-Lbs

or

0-70

Nom) Feeler gauge Pressure gauge Spark plug gap gauge Flywheel puller Gear separator Cylinder ridge reamer Piston ring compressor Piston ring spreader Cylinder hone

Wire brush

Piston groove cleaner Outside micrometer set

(0

to

4

in.)

Telescoping gauge set

(1

/2

in.

to

6

in.)

Hole gauge

(0.300

in. to

0.400

in.)

Valve Seal Replacement

Tool

4

Valve seat cutter

Generator and Control

Tools

Lead or dead-blow hammer Battery hydrometer VOM multi-tester

Frequency meter Armature growler

Load test panel Jumper wires Fan hub assembly holding

tool

SAFETY

CONSIDERATIONS

Always consider the safety aspects of any service procedure. Generator sets present several hazards that the serviceperson must be aware of to safely complete the job. Read through the safety precautions listed on the inside cover and familiarize yourself with the various hazards shown in Table

5-1.

Once the hazards are known, approach the job with a safety conscious attitude. Being safety conscious

is

the most effective way to

avoid injury

to

yourself or others. Reduce the chance that an accident will occur by adopting the following safeguards.

Safeguards

to

Avoid

Hazards

0

Use Personal Protection

-

Protect your body by

wearing the appropriate safety equipment. Protective clothing includes safety shoes, gloves, safety glasses, and hard hats. Leave rings and jewelry off and do not wear loose clothing that might get caught on equipment.

0

Work to Reduce the Hazard

-

The workshop area

and all pieces of equipment used can contribute

to

reducing the hazard potential. Keep guards and shields in place on machinery and maintain equip-

ment in good working condition. Store flammable

liquids in approved containers away from open flame, spark, pilot light, cigarette, or other ignition

source. Keep the workshop clean and well-lighted, and provide adequate ventilation. Keep fire extinguishers and safety equipment nearby and be pre-

pared

to

respond

lo

an emergency.

5-1

TABLE

5-1

HAZARDS

AND

THEIR SOURCE

Fire and Explosions

-Leaking or spilled fuel

-Hydrogen gas from battery

-Oily rags improperly stored

-Flammable liquids improperly stored

-Hot exhaust pipes

-Hot engine and generator surfaces

-Electrical short in

DC

wiring system

-Carbon monoxide from faulty exhaust pipes, joints, or hangers

-Operating generator set where exhaust gases can accumulate

Burns

0

Poisonous Gases

0

Electrical Shock

(AC)

-Improper generator set load connections

-Faulty

RV

wiring

-Faulty electrical appliance

-Faulty generator set wiring

-Working in damp conditions

-Jewelry touching electrical components

-Jewelry or loose clothing catching

0

Rotating Machinery

in moving parts

Slippery Surfaces

Heavy Objects

-Leaking or spilled oil

-Removing generator set from

RV

-Removing heavy components

0

Develop Safe

Work

Habits - Unsafe actions are

identified as the cause of most accidents involving

the use of

tools

and machines. Be familiar with the

equipment and know how to use

it

safely. Use the

correct

tool

for the job and check its condition before starting. Observe the warnings and cautions in this manual and take special precautions when working around electrical equipment.

Do

not work

alone if possible and do not take risks.

Be prepared

if

an accident does occur. Numerous agencies such as the Red Cross and your local police and fire departments offer basic courses in first aid, mouth-to-mouth resuscitation, and fire control. Take advantage

of

these offerings

so

you are ready to

respond when an accident happens. Learn

to

be safety conscious and make safe practices a part of your work routine.

Do

not work when tired or after consuming any

alcohol or drug that makes the operation of equipment

unsafe.

SET

REMOVAL

Some service procedures will require removing the generator set from the coach. While there are many variations, generator set installations are generally classified as either conventional compartment mount

or

under-the-floor mount. In a compartment mount installation, a special compartment (see Figure

5-1)

is built

into the coach

to

house the generator set. The compartment is constructed with a vapor tight barrier that seals

off

the generator set from the coach interior. The generator set is usually fastened to the floor of the compartment which must be able to support the weight

of

the set. Access

to

the compartment is through a door

located in the exterior of the coach. With the under-the-floor mount installation (see Figure

5-2),

special brackets are used to suspend the genera-

tor

set under the floor

of

the vehicle. The mounting

brackets bolt to special support members that are built into the vehicle framework. The generator set is mounted near the exterior

of

the vehicle. Access

is

provided

through a door located in the exterior of the vehicle.

Because of the wide variety

of

generator set installa-

tions,

it

is not possible to specify the exact removal

procedures for each generator set.

If,

after examining

the installation, a satisfactory method for removing the

set cannot be determined, contact the

RV

coach manu-

facturer to obtain their recommendations before

attempting

to

remove the set from the coach.

~WARN~NG

Generafor sets are heavy and can

m

result in severe personal injury if

dropped during removal.

Use

adequate lining devices

to

provide sufficienf support for the set. Keep hands

and feet clear while lining.

Special fuel handling procedures are required when removing an LP gas (propane) powered set. The fuel system must be purged of

LP

gas before the set can be

safely removed from the coach. Follow the purging

procedure before attempting to remove an LP gas powered set

If

the generator set is powered bygasoline,

proceed to the appropriate set removal section.

AWARN~NG

LP-Gas (Propane) is exfremely flam-

m

mable and poisonous, and can result

in severe personal injury or deafh

if

accidentally ignited or inhaled. Eliminate all possible sources of ignition such as open flame, sparks, pilot lights, cigarettes, and arc-producing machinery

or

switches before purging LP-gas from the fuel system. Provide adequate uenfilafion to dissipate LP-gas as

it

is

released. (Propane gas will sink to the ground and is not easi/y detected.)

b

5-2

-

FLOOR

FIGURE

5-1.

TYPICAL COMPARTMENT MOUNT INSTALLATION

M-1723

5

-3

Disconnecting Set from

RV

Systems

Disconnect the following items from the generator set. Refer

to

Figures

5-1

and

5-2

for component locations in

typical generator set installations. Some installations may require partial removal of the set

to gain access

to

the battery cable, fuel line, and other connections. Read this section before starting set removal.

1.

Disconnect the vehicle negative

(-)

battery cable at

the battery terminal.

2.

Disconnect the generator set negative

(-)

battery

cable at the battery terminal.

3.

Disconnect the generator set positive

(+)

battery

cable from the wire harness.

4.

Disconnect the remote control wire plug from the

generator set housing.

5.

Disconnect the generator load wiresatthe RVelec-

trical system junction box. Tag the

RV

circuit wires

for positive identification when reconnecting.

6.

Loosen the conduit connector and pull the load

wires and flexible conduit free of the junction box.

7.

Disconnect the tailpipe from the muffler or discon-

nect any support brackets or hangers attached

to

the tailpipe to allow set removal.

8.

Disconnect the fuel line at the generator set housing. Securely plug the end of the fuel line to prevent fuel leakage or an accumulation of explosive gasoline vapor.

Gasoline vapor is extremely flam-

mable and can result in severe personalinjury or deathifignited. Make certain all fuelline openings are plugged to prevent gasoline vapor from accumulating. Before disconnecting the fuel line, be

certain there are no ignition sources such

as

flame, spark, pilot light, cigarette, etc., near the generator set. Keep an

AEC

type fire extinguisher nearby.

LP-Gas (Propane) Purging Procedure

To

purge the LP-gas from the set fuel system, close the shut-off valve at the fuel tank and then start the generator set. Allow the generator set to operate until it runs out of fuel. Crank the set a few times after it stops to make sure the fuel system

is

completely purged of all LP-gas

fuel.

If

the generator set cannot be operated, move the

RV

coach to an outdoor location that is well-ventilated and is away from fire or flame. Disconnect both the vehicle negative

(-)

battery cableand the generator set negative

(-)

battery cable from their respective battery terminals. Close the fuel shutoff valves at the fuel tank for both the generator set fuel supply system and the appliance (stove, heater, etc.) fuel supply system. In addition, close

the fuel shutoff valves at each appliance.

L

P-Gas (Propane) is extremely ilam-

@@!@%I

mable and poisonous, and can result in severe personal injury or death if accidentally ignited or inhaled. Eliminate all possible sources of ignition such as open ilame, sparks, pilot lights, cigarettes, and arc-producing machinery or switches before purging

L

P-gas from the fuel system. Provide adequate ventilation to dissipate LP-gas as it is released. (Propane gas will sink

to

the ground and is

not easily detected.)

Slightly open the fuel line where it connects

to

the

generator set just enough to allow the LP-gas

to

slowly

escape. Don’t open the fitting

too

much ora large quan-

tity of gas will be released.

Disconnect the fuel supply hose from the carburetor

and hold it clear

of

the set. Press in and hold the primer

button on the regulator to release LP gas from the set

fuel system. When

no

more gas can be heard escaping

from the open end of the fuel supply hose, reconnect the

hose

to

the carburetor and proceed to the appropriate

set removal section.

Removing Conventional Compartment Mounted Set from

RV

When the generator set has been disconnected from the

electrical, exhaust, and fuel systems, examine the set mounting and support system. Locate all mounting bolts and support members for the set. In most installations,

the generator set housing will be bolted

to

the coach

framework. Depending on the installation, the set may

be removable from the side, back, or bottom. Verify that the generator set is adequately supported

before loosening any of the mounting bolts or support members. The most satisfactory way to lift or move the generator set is

to

use a forklift truck.

The generafor set is heavy and can

liGZi%l

result in severe personal injury if

dropped during removal. Use the recommended remo-

val techniques and keep hands and

feet

clear while

removing mounting bolts.

Removing Underfloor Mounted Set From

RV

When the generator set has been disconnected from the electrical, exhaust, and fuel systems, the set may be

removed for major service work. The generator set is mounted on support brackets that are bolted

to

the

underside

of

the floor on the vehicle or trailer and to the

generator set housing. The generator set is completely suspended underneath

the floor

of

the

RV

by

the support brackets. To avoid dropping the set during removal, follow the recommended set removal procedures.

.

5-4

The generator set

is

heavy and can

ljiEiSl

result in severe personal injury if

dropped during removal. Use fhe recommended remo-

val techniques and keep hands and feet clear while removing mounting bolts.

Park the recreational vehicle on as level a surface as possible. Then follow these steps very carefully.

1.

Put the vehicle in its park position, lock the brakes,

and remove the keys (if applicable). Make sure no

one moves the vehicle while performing this procedure.

Dropping the generator set can

lAWARNlNGI

result

in

severe personal injury

or

death. Make sure no one moves the vehicle

during this procedure and that the procedure

is

performed very carefully and only as instructed.

2.

3.

4.

5.

6.

Use aforklifttruckto supportthe weightof thegener-

ator set at the points shown in Figure

5-3.

Raise the forklift just

so

it

makes contact with the

bottom

of

the generator set housing, then put a little upward pressure under the set. Verify that the weight of the generator set

is

supported by the forks before

proceeding.

Remove the bolts that secure the generator set to

the side mounting brackets and rear mounting

braces. Slowly lower the generator set until it clears all

obstructions and can be safely

moved

out from

under the vehicle.

When reinstalling the generator set, be sure that all bolts, brackets, and electrical, exhaust, and fuel system components are connected exactly as they were before removal.

M-1725

5-5

Section

6.

Engine

=

Primary

Systems

INTRODUCTION

The engine primary systems include the following:

The engine primary systems can often be serviced without removing the generator set from the recreational

vehicle and without major disassembly of the set. Use the following troubleshooting guide

to

help locate prob-

lems related

to

the engine primary systems. Refer

to

Troubleshooting Generator Set Control for problems related to starting the generator set.

0

Exhaust System

0

Cooling System Ignition System

0

Crankcase Ventilation System

0

Governor

0

Fuel System

0

Electric Starter

TROUBLESHOOTING ENGINE PRIMARY SYSTEMS

1-1

Many troubleshooting procedures present hazards which can result in severe

personal

injury

or

deafh. Only qualified service personnel with knowledge of fuels, electricity, andmachinery hazards

should perform service procedures. Review safefy precaufions

on

inside cover page.

TROUBLE

Engine Misfires

~~ ~

Engine Backfires

POSSIBLE

CAUSE

-

1.

Faulty ignition due

to:

a. worn or fouled spark plug b. faulty magneto assembly c. faulty ignition coil d. faulty plug wire e. incorrect ignition timing

2. Lean fuel mixture due

to:

a. incorrectly adjusted

fuel mixture screws

*b. incorrect float level

c. dirt in carburetor d. vacuum leak

3.

Contaminated fuel

4.*Carburetor icing

5.

Incorrect timing due

to:

a. defective magneto b. incorrect flywheel or

generator mounting

*Gasoline sets only

1. Faulty ignition due

to:

a. incorrect spark plug gap

b. incorrect ignition timing

2. Lean fuel mixture due to: a. incorrectly adjusted

fuel mixture screws

*b. incorrect float level

c. dirt in carburetor d. vacuum leak

3.

Mechanical damage

to

engine

*Gasoline sets only

CORRECTIVE ACTION

la. Replace spark plug

1

b. Replace magneto assembly

1

c. Test coil and replace

if

necessary

1 d. Check spark plug wire and replace le. Rotor or fan hub improperly installed

coil assembly

if

necessary

2a. Adjust carburetor main

and idle adjustment screws 2b. Adjust carburetor float level 2c. Disassemble carburetor and clean

all passages 2d. Locate leak and correct as required

3.

Drain fuel tank and refill with

fresh fuel

4.

In cold weather, place air preheater

in winter position

5a. Replace magneto assembly

5b.

Check for proper installation, see

Generator Service section

1

a. Reset spark plug gap

1

b. Replace magneto assembly

2a. Adjust carburetor main

and idle adjustment screws

2b.

Adjust carburetor float level

2c. Disassemble carburetor and clean

all internal passages

2d. Locate leak and correct as required

3.

See Engine Block Assembly section

6-1

TROUBLESHOOTING ENGINE PRIMARY SYSTEMS

Many troubleshooting procedures present hazards which can result in severe personal injury

or

laWAR"Gl

death. Only qualifiedservice personnel with knowledge

of

fuels, electricity, andmachinery hazards

should perform service procedures. Review safety precautions

on

inside cover page.

Engine Lacks Power

POSSIBLE

CAUSE

1.

Faulty ignition due

to:

a. incorrect spark plug gap b. incorrect ignition timing

2.

Dirty air cleaner

3. Restricted fuel flow due

to:

*a. Plugged fuel filter or *b. faulty fuel pump

dirty or defective.

4.

Incorrect fuel mixture due

to:

a. incorrectly adjusted

fuel mixture screws

*b. incorrect float level or

c. dirt in carburetor d. vacuum leak

c.

LPG

-

Regulator or fuel solenoid

5.

Exhaust system blocked or restricted

6.

Incorrect valve lifter

7.

No

load speed set

too

low

8.

Excessive engine wear or

damage to engine

9.

Carburetor air preheater set incorrectly

*Gasoline sets only

1.

Restricted air flow due

to

dirt or debris blocking air inlet or outlet

clearance or defective valve(s)

2.

Dirt or oil covering engine

3. Incorrect ignition timing

4.

Cooling fan plugged or broken

cooling fins

5.

Lean fuel mixture due to:

a. incorrectly adjusted

fuel mixture screws

*b. incorrect float level

c. dirt in carburetor

*Gasoline sets only

CORRECTIVE

ACTION

1

a. Reset spark plug gap

1

b. Replace magneto assembly

2.

Replace air cleaner

3a. Replace fuel filter 3b. Test fuel pump and replace if faulty 3c. Refer

to

LPG

Fuel section.

4a. Adjust carburetor main

and idle adjustment screws 4b. Adjust carburetor float level 4c. Disassemble carburetor and clean

all internal passages 4d. Repair vacuum leak.

5.

Locate and remove cause of blockage, remove and clean spark arresting

screen

6.

Adjust valve lifters/inspect valves

(see Engine Block Assembly section)

7.

Adjust governor setting

8.

See Engine Block Assembly section

9.

In hot weather, place air preheater

in summer position

1.

Clear away any debris that may restrict airflow to set and do not

use compartment for storage area

2.

Clean away all dirt and oil from engine cooling

fins

3.

Replace magneto assembly

4.

Inspect cooling fan, see Generator Service section

5a. Adjust carburetor main

and idle adjustment screws

5b.

Adjust

carburetor float level

5c. Disassemble carburetor and clean

all internal passages

TROUBLESHOOTING ENGINE PRIMARY SYSTEMS

.

Many troubleshooting procedures present hazards which can result in severe personal injury

or

lAWAR"Gl

death. Only qualified service personnel with knowledge

of

fuels, electricity, andmachinery hazards

should perform service procedures. Review safety precautions

on

inside cover page.

I

TROUBLE

I

Black Exhaust Smoke

I

White or Blue

Exhaust Smoke

Engine Hunts or Surges

POSSIBLE CAUSE

1.

Rich fuel mixture due to:

a. dirty air cleaner

*b. choke sticking

c.

incorrectly adjusted fuel mixture screws

d. dirt in carburetor

*Gasoline sets only

1.

Lean fuel mixture due

to:

*a. incorrect float level

b. incorrectly adjusted fuel

mixture screws

c.

dirt in the carburetor

2.

Contaminated fuel

3.

Excessive engine wear

*Gasoline sets only

1.

Sticking or binding governor linkage

2.

Incorrect governor adjustment

3.

Faulty governor spring

4. Incorrect fuel mixture due

to:

a. incorrectly adjusted

fuel mixture screws

*b. incorrect float level or

c. dirt in carburetor

5.

Governor mechanism worn excessively or motion spring

faulty

6. Fuel supply problem caused by: *a. Faulty fuel pump

b. Contaminated fuel supply

c. Vapor locking

d. Plugged fuel filter

7.

Carburetor icing

*Gasoline sets only

CORRECTIVE ACTION

1

a. Replace air cleaner

1

b. Clean choke and adjust or replace

I

i

n

kag e

1

c.

Adjust carburetor idle and main adjustment screws

Id. Disassemble carburetor and clean

all internal passages

1

a. Adjust carburetor float level

1

b. Adjust carburetor idle and

main adjustment screws

1

c.

Disassemble carburetor and clean all internal passages

2.

Drain and replace fuel

3.

See Engine Block Assembly section

1.

Check linkage alignment and straighten or replace. Clean and lubricate governor linkage

sensitivity

2.

Adjust governor speed and

3.

Replace governor spring

4a. Adjust carburetor main

and idle adjustment screws

4b. Adjust carburetor float level

4c. Disassemble carburetor and clean

all internal passages

5.

See Engine Block Assembly section

6a. Check fuel pump and replace

6b. Drain and refill fuel supply

6c. Check for cause of overheating 6d. Replace fuel filter

if

defective

*7.

In cold weather, place air preheater in winter position

6-3

TROUBLESHOOTING

ENGINE

PRIMARY

SYSTEMS

Many troubleshooting procedures present hazards which can result in severe personal injury or

death. Only qualified service personnel with knowledge of fuels, electricity, and machinery hazards

should perform service procedures. Review safety precautions on inside cover page.

TROUBLE

High Oil Consumption

[Note: New engines sometimes have high oil consumption during break4 n)

Engine Shuts Down and Will

Not

Restart

~ ~ ~ ~~

POSSIBLE CAUSE

1.

Oil viscosity is too light

2.

Crankcase breather valve is

or oil is diluted

dirty or defective

3.

Oil leaks

4.

Excessive engine wear

5.

Intake valve seal worn or defective.

6.

Light loading

~

~~

1.

Low oil level

2.

Low oil level switch defective

3.

Worn spark plug

4.

Faulty fuel system

CORRECTIVE ACTION

1.

Drain oil and refill with correct

viscosity oil

if

defective

2.

Clean crankcase breather and replace

3.

Locate source

of

leak and repair as

4.

See Engine Block Assembly section

required

5.

See Engine Block Assembly section

6.

Do not run set at no load for long periods

of

time

1.

Add oil as required

2.

Replace oil level switch (see

3.

Clean or replace spark plug

4.

Refer to Fuel System section for

test and service procedures

Engine Block Assembly section)

.

6- 4

EXHAUST

SYSTEM

The

condition

of

the exhaust

system

is

critical

on

RV

generator sets because

of

the possibility

of

exhaust

gases entering the vehicle. The exhaust system consists

of

the muffler and muffler support brackets, exhaust pipe, clamps, and hangers needed for installation

of

the exhaust pipe. Figure

6-1

shows a typical exhaust system for a compartment mount generator set. The following section covers the service procedures for the exhaust system.

The generator must be shut down and the exhaust system serviced immediately

if

inspection reveals leaking joints

or

connections, loose

fasteners,

or

broken, corroded,

or

damaged components.

Always replace worn components with new original equipment replacement parts.

Do

not attempt

to

repair a broken exhaust pipe or manifold by welding and do not replace worn out components with parts that

do

not meet factory specifications. The muffler isa sparkarrester type muffler that is Forest Service Approved and meets code requirements. Failure

to

provide and maintain a spark arrester muffler can be in violation of the law. Contact an Onan distributor for approved replacement exhaust parts.

rn

Inhalation

of

exhaust gases can

llEEE4

result in severe personal injury

or

death. Modifying the exhaust system can allow poisonous exhaust gases to enter the coach. Use only original equipment replacement parts when servicing fhe exhaust system. Unauthorized modifications will also void the warranty and cancel the UL ListingKSA Certification. Liability

for

injury

or

damages due to unauthorized modifications becomes the responsibility

of

the person making the change.

3-

TYPICAL SIDE EXHAUST

K:

W

TYPICAL

A

REAR

EXHAUST

TAILPIPE NOT

FURNISHED

BY

ONAN

WS-1170-3

FIGURE

6-1.

COMPARTMENT MOUNT EXHAUST SYSTEM

Disassembly:

1.

2.

3.

4.

5.

6.

Allow the exhaust system

to

cool down before

servicing. Loosen the exhaust pipe clamp securing the

exhaust pipe to the muffler. Remove exhaust pipe hanger(s) and lower exhaust

pipe. The generator set must be removed from the vehicle

and the outer housing removed

to

access the

muffler for servicing. See Set Removal, section

5.

Remove the mounting nuts securing the muffler flange

to

the engine and remove theexhaust gasket.

Remove the

bolts

securing the mounting brackets to

the muffler.

Assembly:

Obtain the required replacement parts then

proceed as indicated.

Exhaust gas can cause severe per-

-

sonal injury

or

death.

To

prevent exhaust leaks, install gaskets, clamps, straps, and hardware as specified. Inspect all components even

if

not replaced or worked on.

1.

Install a new exhaust gasket. Mount the muffler

flange

to

the engine and tighten mounting nuts to

the specified torque.

2.

Install muffler support bracket mounting bolts and secure

to

the specified torque.

3.

Install generator set housing and reinstall the generator set.

4.

If

replacing the original exhaust tailpipe, refer to the

Tailpipe Recommendations section.

6-5

5.

Attach the exhaust pipe to the outlet of the muffler using a U-bolt type automotive muffler clamp marked

1-1

/8 inch

I.D.

6.

Attach an automotive type tailpipe hanger every 2 to

3

feet

(0.6

to

0.9

meters). In addition, the exhaust system must be supported at or near the perimeter of the vehicle to prevent the tailpipe from being damaged and pushed up under the vehicle skirt.

Excessive vibration transfer and

@%!!@!I

exhaust pipe damage can be caused be angular mounting. Tailpipe hanger clamps must be mounted directly above the com-

ponent being supported and not at an angle.

7.

Run thegeneratorset for five minutesand checkthe

entire exhaust system (visually and audibly) for

leaks

or

excessive noise. Shut down the generator

set and correct any problems immediately.

Tailpipe Recommendations

Tailpipes must meet several design specifications

to

provide safe generator set operation. It is necessary to use an Onan-specified exhaust kit designed specifically for use with this generator set.

Kits are available in two exhaust lengths: 18

to 25

inches

(457-635 mm) and over

25

inches (635 mm).

Refer to the following guidelinesfor selecting and locating the tailpipe.

Inhalation of exhaust gases can

lawnRNlNGI

result in severe personal injury or death. Exhaust gases can enter the vehicle interior if the tailpipe is damaged, missing,

or

improperly installed. Use the appropriate Onan-specified exhaust kit and install according to the instructions provided

with the kit.

Use

1-1

/2

inch

O.D.,

18

gauge aluminized or stainless

steel tubing for tailpipe.

Do

not use flexible tailpipe since

it might break due to road shock and vibration.

Install exhaust tailpipe at least 3 inches

(76

mm)

away from any combustible material (wood felt, cotton, organic fibers, etc.),

or

be

so

located, insulated,

shielded, that it does not raise the temperature of any

cornbustiblematerial more than

1

17°F(650C)above the

ambient air inlet temperature. The exhaust system must extend a minimum of

1

inch

(25

mm) beyond the perimeter of the vehicle.

If

the

generator set tailpipe is on the same side

of

the vehicle as the air intake, terminate the tailpipe downward and aft of thegenerator set air intake to reduce the possibility of recirculating exhaust gases.

l

AWARNING

1

EXHAUST

GAS

IS

DEADLY!

Exhaust gases contain carbon monoxide, an odorless and colorless gas. Carbon

monoxide

is

poisonous and can cause unconsciousness and death. Symptoms of

carbon monoxide poisoning can include:

Dizziness

Nausea

0

Muscular Twitching

0

Headache

0

Vomiting

0

Weakness and Sleepiness

0

Throbbing

in

Temples

0

Inability to Think Coherently

IF

YOU

OR

ANYONE ELSE EXPERIENCE ANY

OF

THESE SYMPTOMS, GET OUT

INTO THE FRESH AIR IMMEDIATE1

Y.

If

symptoms persisf, seek medical atten-

tion. Shut

down

the unit and

do

not operate until

it

has been inspected and

repaired. Never sleep in vehicle with the generator set running unless the vehicle interior

is

equipped with an operating carbon monoxide detector. Protection against carbon monoxide inhalation also includes proper exhaust system installation and visual and audible inspection of the complete exhaust system at the start

of

each

generator set operation.

1

-RV

6-

6

Do

not terminate the exhaust tailpipe under the fuel tank

fill spout

to

prevent spilled fuel from being ignited by a

hot

tailpipe.

Do

not

terminate the exhaust tailpipe under

any door or operable window.

1

No

part

of

the exhaust system shall intrude into the

departure angle

or

approach angle unless it is adequately protected by a skid bar or other protection device. See Figure

6-2.

Use

a sufficient number

of

L

hangers to prevent damage or dislocation

of

the system.

Exhaust gases present the hazard

of

severe personalinjury or death.

Do

not terminate tailpipe

under

the vehicle. Direct exhaust

gases away from any vent, window, door,

or

any

open-

ing which can be opened and

is

not permanently

sealed from the vehicle living space.

Do

not mount any

protion

of

the exhaust system into the departure angle or approach angle unless it is adequately protected. Use suificient number

of

hangers toprevent damage

or

dislocation

of

the exhaust system.

[BCAUTION)

Excessive exhaust back pressure can cause engine damage.

If

tailpipe

deflector is used, make sure

it

is

large enough

io

pre-

vent back pressure.

DEPARTURE

ANGLE

CLEARANCE

(REAR

VIEW)

LINE

ANGLE

Y-1689-4

FIGURE

6-2.

TAILPIPE INSTALLATION

.

6-

7

COOLING

SYSTEM

A

constant airflow is critical for engine and generator

cooling to prevent excessive heat build-up.

A

centrifugal fan on the generator end of the set provides the required airflow. The fan draws cooling air in through the air inlet, into the generator and across the engine cooling fins, then discharges the heated air through the air outlet. See Figure

6-3.

Inhalation of exhaust gases can

EiEEEGI

result in severe personal injury

or

death. Never use discharged cooling air for heating the

vehicle interior since discharged cooling air can con-

tain poisonous exhaust gases.

The generator housing air inlet is sized to allow the required flow rate of cooling air. The air inlet opening must be kept free of any obstructions to avoid restricting airflow. Dirt, dust, or other debris that may clog the air duct openings should be removed during periodic maintenance. Dirt might also become lodged between the cooling fins on the engine block and cylinder head.

If

this happens, heat transfer is greatly reduced and over-

heating can occur

if

the fins are not cleaned.

The cooling system consists of the set housing and base assembly enclosure, insulation duct, scroll assembly, fan hub assembly, air duct, and air guide. The following section covers service procedures for the cooling system.

Disassembly:

Remove the generator set as described in

the Set Removal section.

1.

2.

3.

4.

Follow the generator set disassembly procedures

(section 8) through the scroll assembly removal.

Inspect and clean the fan hub assembly using a brush or low pressure (less than

30

psi) compressed

air.

If

the fan blades are damaged, remove the fan

hub assembly as described in section 8and replace

the fan.

Remove the top and bottom air guide housings (cowling) for access to’the engine cooling fins for cleaning.

Use a brush or low pressure compressed air

to

remove any dirt or debris that may be lodged on the

engine cooling fins.

?

1nspection:Remove

the spark plug boot and inspect the engine cooling fins by viewing the area around the spark plug.

If

the engine is clean in this area and the air inlet area is clean, disasembly for cleaning the engine will not be necessary.

If

debris is visible in the area of the

spark plug or at the air inlet area, proceed

to

the Disas-

sembly section.

Spark

Plug

(E2)

Remove the spark plug and inspect the electrode.

If

the

spark plug has carbon deposits, use a wire brush

to

clean

it.

If

the spark plug is badly fouled or deformed,

replace it. Measure and reset the spark plug gap

to

0.025

inches

(0.64

mm). An examination of the spark plug can often help diagnose an engine problem. Refer to the following spark plug conditions:

.

Assembly:

Cooling system assembly is in reverse order

of disassembly. Follow the generator assembly instruc-

tions (section 8) for installing the fan hub assembly, if

removed for cleaning or replacement.

Overheating can result in engine damage.

To

avoid overheating, never

operate the generator set with the access cover

or

any

of

the cooling system parts removed.

IGNITION

SYSTEM

The ignition system consists of the magneto assembly, ignition coil, spark plug and ignition wiring.

If

a problem with the ignition system issuspected, the spark plug can be inspected and an ignition spark check can be made without removing the genset from the vehicle. Perform the spark plug, ignition coil and ignition wiring checks before proceeding to the Magneto Assembly section.

Electrical shock can cause severe personal injury or death. Do not

touch electrical wiring

or

components during testing.

Disconnect electrical power by removing the starting

battery negative

(-1

cable before handling electrical

wiring

or

components. Do not connect meters while

circuit is energized.

>

-----

t

CS-1341-2

FIGURE

6-3.

COOLING

AIRFLOW

Carbon Fouled - Check for a poor high tension lead connection, faulty choke operation, rich fuel mixture or dirty air filter.

Oil Fouled

-

Check for low compression.

Burned or Overheated

-

Check for leaking intake

manifold gasket, lean fuel mixture or incorrect spark

Plug type-

6-

8

0

Splash Fouled - Check for accumulated combustion chamber deposits. See Cylinder Head section.

0

Light Tan or Gray Deposits - Normal plug color.

If

the spark

plug

is in good condition,

proceed

to

the Ignition

Coil section.

SPARK

PLUG

GAP

-(SEE

SPECIFICATIONS)

ES-1462

FIGURE

6-4.

MEASURING PLUG GAP

Ignition Coil

(TI)

The ignition coil is a transformer that steps up the mag-

neto output voltage to about

20,000

volts for spark plug firing. The coil consists of a primary and a secondary winding. Perform the following checks:

Ignition

Spark Check:

1.

Make sure the engine oil level is adequate and that

the genset

is

level.

2.

Remove the spark plug, reconnect the spark plug lead and ground the plug side electrode to bare metal on the engine.

3.

Do

not touch the plug or plug wire during testing.

Crank the engine and observe the plug. A good

spark should be observed.

If

no spark is observed,

proceed to the coil winding check.

Coil

Winding

Check:The ignition coil is located below

the lower right corner

of

the access cover. Disconnect the coil ground lead, primary lead and spark plug lead from the spark plug. The coil can be removed from the set for testing. See Figure

6-5.

SPARK

rwti

BOOT

.

TERMINAL/

1

(PRIMARY)

1.

2.

3.

Inspect the terminal and leadsfor signs

of

corrosion

or

looseness and look for cracks, dents or other

damage. Look for evidence

of

electrical leakage

around

the high

tension

connection (indicated

by

carbon tracking). Replace a coil with any defects.

Measure the primary winding resistance. Connect

one ohmmeter lead

to

the primary terminal and the other lead to the ground lead ring terminal. The resistance should be approximately

0.5

ohms at 75OF (24°C). Replace the coil if a high or low reading

is

measured.

Measure the secondary winding resistance. Connect one ohmmeter lead to the spark plug connector, inside the boot,and the other lead to the ground lead ring terminal. The resistance should be approximately 1,1000hmsat75°F(240C). Replacethecoil

if

a high or low reading is measured.

If

nospark

is

seen and the coil windings check good, proceed

to

the Ignition Wiring check.

ignition Wiring

It will be necessary to remove the genset from the vehicle and remove the housing to inspect some of the wiring. The ignition wiring consists of one ground wire

connected to the coil and one ground wire connected to the magneto assembly. One wire from the magneto to the ignition coil primary. One wire from the shut down

circuit (connected to

K3-30)

to the magneto. One high

tension lead from the ignition coil secondary to the

spark plug. Refer to Figure 7-1.

(Do

not disassemble the

set to check the wiring at the magneto at this time.) Thoroughly inspect the ignition wiring for loose connec-

tions and cuts or breaks in the insulation. Test suspect

leads for continuity with an ohmmeter. Use a megger

to

check for breaks in the spark plug lead. Also check

control wiring and relays K3 and

K5

for loose

or

grounded connections.

If

any problems are found, cor-

rect them and repeat the ignition spark check.

If

no problems are found proceed to the Magneto Assembly section.

Magneto Assembly

(G2)

The magneto asembly is a noncontact (breakerless) type that is mounted

to

the generator endbell. As the engine cranks, two permanent magnets on the fan hub assembly pass very close to the magneto inducing a voltage in the coil of the magneto. The voltage from the magneto (approximately

16

to

60

VAC when measured with a digital voltmeter) is supplied to the primary of the ignition coil.

If

no spark

was

seen in the Ignition Spark Check and all accessible ignition wiring checks good, perform the Magneto Assembly Check.

Magneto

Assembly Check: Use a known good (new)

ignition coil.

W

ES-1767

FIGURE

6-5.

IGNITION

COIL

1.

Make sure the cranking circuit and battery are in good condition.

6-9

2.

3.

4.

Disconnect the ignition shut down circuit by locating relay

K3

(Figure 7-3) and removing leads G2-1

and S2-1 from

K3-30.

Separate piggy backed leads

G2-1 and S2-1 and insulate them from each other

and from ground.

Remove the spark plug, reconnect the spark plug lead and ground the plug side electrode to bare metal on the engine.

Do

not touch the plug or plug wire during testing.

Crank the engine and observe the plug.

A

good

spark should be observed.

If

no spark is observed,

the magneto or wires connected

to

the magneto are

the most likely cause. Refer

to

the Generatorsection

for generator disassembly

to

access the magneto

assembly.

CRANKCASE

VENTILATION

SYSTEM

The crankcase breather prevents pressure from build-

ing up in the crankcase.

It

also prevents oil contamina-

tion by removing moisture or gasoline vapors and other

harmful blow-by materials from the crankcase. These vapors are routed

to

the carburetor where they are mixed with the incoming air and burned in the combustion chamber.

A

sticky breather valve can cause oil leaks, high oil consumption, rough idle, reduced engine power, and a rapid formation of sludge and varnish within the engine.

Crankcase Breather Service

If

the crankcase becomes pressurized, as

evidenced by

oil

leaks at the seals, use the following procedures to service.

Remove the breather tube and the head cover (see Engine Block Assembly, Section

9)

then remove the breather from the cylinder head and inspect it. The reed valve must be flat with no sign of creases or other damage.

If

the breather is defective, replace it.

If

the

breather is dirty, clean it in parts cleaning solvent.

Most parts cleaning solvents are flammable and can result in severe

personal injury

if

used improperly. Follow the manu-

facturer’s recommendations when cleaning parts.

Check breather tube and air passages for clogging and clean as required.

GOVERNOR

The governor controls engine speed which directly affects the voltage output and frequency

of

the genera-

tor. An increase in engine speed will cause a corres-

ponding increase in generator voltage and frequency. A decrease in engine speed will cause a corresponding decrease in generator voltage and frequency. The governor maintains a constant engine speed under chang-

ing load conditions

so

that generator voltage and fre-

quency do not vary.

Governor Adjustments

Contact with moving parts can cause severe personalinjury Keep clothing,

jewelry, bands, and fingers dear while adjusfing the

governor.

4

A hof generator set can cause severe burns. Always allow fhe generator

set to cool before touching any components

or

remov-

ing any parts.

Before making governor adjustments, run the unit about 15 minutes under 50percent load

to

reach normal oper-

ating temperature.

If

governor is completely out of adjustment, makea preliminary adjustment at no load to first attain a safe voltage and speed operating range.

An accurate voltmeter and frequency meter should be

connected to the generator in order to correctly adjust

the governor (accuracy

of

0.3%

on frequency and

0.5%

on voltage). A small speed drop not noticeable without instruments will cause an objectionable voltage drop.

A

binding in the governor shaft, governor linkage, or carburetor throttle will cause erratic governor action or alternate increase and decrease in the engine speed (hunting).

A

rich or lean carburetor adjustment can cause hunting and a fouled spark plug can cause missing and hunting. Springs tend

to

lose their calibrated tension through fatigue and after long usage and may require replacement.

If the governor action is erratic after adjustments are made, replace the spring.

If

this does not improve operation, the problem may be within the governor mechanism (see Engine Block Assembly, section

9).

Adjustments

to

the governor should be made in the

following sequence.

The carburetor fuel mixture screws must be cor-

rectly adjusted before governor adjustments are made.

If

the carburetor needs adjusting, refer

to

the Mixture Screw Adjustments in this section before making any adjustments to the governor.

Set the carburetor throttle stop screw as specified in Carburetor Mixture Screw Adjustments (step

5).

Check the governor linkage for binding or excessive looseness. Check the motion spring for bending or damage and straighten or replace as needed.

With unit operating at no-load, adjust the speed adjustment screw (see Figure 6-6) on the governor linkage

to

obtain 62.5

f

0.5

Hz, at between 120 and

126 volts on 60 hertz units. Set

50

hertz units to

obtain 52.0

k

0.5

Hz

at between 220 and 231 volts

for

220

volt units and

240

to

252

volts for

240

volt

units.

6-1

0

.

Voltage

Maximum No-Load Minimum Full-Load

(Typical No-Load) (Typical Full-Load)

60

Hz 50 Hz 50

Hz

(10,2-Wire) (10, 2-Wire) (10, &Wire

120

v

220

v

240

V

126 231 252 1

OB

205

(125) (228) (248)

224

(118) (21 5) (236)

Speed

/

Frequency

Maximum No-Load

Speed (rlmin) Frequency (Hz) (Typical Frequency)

Minimum Full-Load

Speed (rlmin) Frequency (Hz) (Typical Frequency)

3

p"

3780 3150 3150

63

52.5 52.5

(62.5) (52)

(52)

3570 2940 2940

59.5

49 49

(59.5-60.5) (49.5-50.5) (49.5-50.5)

*rp4c

.$f

GASOLINE MODEL

M.1877.1S

I.

SPEED

ADJUSTMENT

SCREW

SENSITIVITY

GASOLINE FUEL

SYSTEM

The fuel system must be in good condition and be prop-

erly

adjusted

for

efficient generator set operation. The

main components

of

the

fuel

system

are

the

air

filter assembly, carburetor, choke, intake manifold, fuel filter, fuel pump, and air preheater. When servicing, use the procedures in the following sections.

Air Filter and Preheater Assembly

The air filter and preheater assembly consists

of

the air filter cover, air filter, scroll assembly, preheat door, preheat linkage, preheat hose and intake air stove portion of the muffler assembly. See Figure

6-7.

The air filter, preheat linkage, preheat door, and preheat air hose can be checked without removing the generator set from the vehicle. Remove the access cover and the air filter cover. Remove the air filter retainer and pull out the air filter. Inspection of the air filter and preheater operation can be made at this point.

If

a problem exists with operation of the preheat door,

remove the generator set (see Set Removal, section

5)

and remove the enclosure assembly. Check preheater linkage and adjust as required.

If

the problem is within the scroll assembly, follow the Generator Removal procedures (Section

8)

through the scroll removal step

and repair or replace as required.

AIR

FILTER

PRE-HEATER

HOSE

/

ADJUSTMENT

:

SCREW

M-1677

/

LPG MODEL

&f

FIGURE

6-6.

GOVERNOR ADJUSTMENTS

6-1

1

\

FS-1757-3

COVER

FIGURE 6-7. AIR FILTER AND PREHEATER ASSEMBLY

Carburetor and Intake Manifold

Assembly

Fuel presents the hazard of fire

or

explosion which can cause severe

personalinjury

or

death. Plug fuel lines when servicing

the tuel system

to

prevent fuel leakage.

Do

not permit

any flame, spark, pilot light, cigarette,

or

other ignition source near the fuel system. Keep an ABC type fire extinguisher nearby.

The carburetor and intake manifold assembly consists of the intake manifold, carburetor, choke pulloff and governor control linkages. See Figure

6-8.

Disassembly:

Use the following procedures to remove and disassemble the carburetor and intake manifold assembly.

Remove the generator set from the vehicle (see Set Removal, section

5)

and remove the set enclosure.

Remove the choke assembly mounting bolts and disconnect the choke linkage from the carburetor. Remove the vacuum hose from the intake manifold.

Remove the governor control linkage and spring

attached

to

the carburetor.

CARBURETOR

ASSEMBLY

4.

Disconnect the fuel line and plug

to

prevent fuel

leakage.

5.

Remove the two bottom intake manifold mounting bolts that connect the intake manifold to the cylinder head.

6.

Remove the carburetor and intake manifold as an

assembly.

7.

Remove the intake manifold gaskets and plug the intake port to prevent loose parts from accidentally

entering the engine.

8.

Remove the two screws that secure the carburetor

to the intake manifold and carefully separate the

carburetor from the intake manifold.

,

Assembly:

Reverse order of disassembly. Use new gaskets between the intake manifold and engine and between the carburetor and the intake manifold. Tighten mounting screws to specified torque.

MOUNTING

BOLTS

FS-1758

FIGURE

6-8.

CARBURETOR

AND INTAKE MANIFOLD ASSEMBLY

6-1

2

Carburetor Mixture Screw Adjustments

The

most

common

cause

of

poor carburetion

is

unsatis-

factory adjustment

of

the

idle

or

main

mixture

adjust-

ment screws. Significant variation from the correct settings may result in serious engine trouble. An overly rich mixture not only wastes fuel, but can increase engine wear by washing the lubricant from the cylinder walls and diluting the crankcase

oil.

An overly lean mixture

results in a

loss

of

power, flat spots

in

acceleration,

and

a greater tendency

to

burn valves and spark plugs.

Mixture screw adjustment should be checked with every engine tune-up and whenever a carburetion problem is suspected. Before adjusting, be sure the ignition system

is

working properly and thegovernor is correctly set. The limiter cap on the main mixture screw should not be removed unless the carburetor is totally out of adjustment or has been overhauled. With the limiter cap removed, use the mixture settings in Table 6-2 for preliminary adjustments. Turn the mixture screws in until lightly seated, then turn out the specified number of

turns.

*

L

TABLE

6-2.

CARBURETOR ADJUSTMENT SPECIFICATIONS

MIXTURE SETTING FLOAT

LEVEL

9/16 i 1/16

in.

I

(14

*

Inm’

I

T

H

R

0

l-r

L

E

STOP

SCREW

ADJUSTMENT

Forcing the mixture adjustment

-1

screws fight will damage fhe needle

and seat. Turn in

on/y

mil

right

fension can be

felt.

AWARNING

Contact with moving parts can cause

severe personal injury. Keep

clothing, jewelry, hands, and fingers clear while adjusting the governor.

A

hot generator set can cause severe

k!@@&l

burns. Always allow the generator

set

to

cool before touching any components or remov-

ing any parts.

Start the engine and allow it

to

run for about

10

minutes.

The location of the adjustment screws

is

shown in Fig-

ure 6-9. Use the following procedure

to

adjust:

1.

2.

3.

4.

5.

6.

7.

Stop the set and connect a voltmeter, frequency meter, and load bank

to

the generator output leads.

Start the generator set and apply a full load. Verify that the frequency is within

60.5

f

1

hertz

(50.0

f

1

hz on

50

hertz units) and adjust the governor speed

adjustment screw

if

necessary

to

obtain required

frequency. Turn the main adjustment screw inward until volt-

age or frequency drop and then outward until voltage or frequency drop again. Locate the point where the voltage and frequency are highest. From this setting turn the main adjustment screw

out

an

additional

1

/4

turn.

Remove the load and verify that frequency is within

62.5

-1:

0.5

hertz

(52.0

5

0.5

hz on

50

hertz units).

Adjust governor speed adjustment nut

if

necessary

to

obtain required frequency.

When the engine is warm, and the set is running at no load, turn the speed adjustment screw (Figure 6-6)

so

that the throttle lever on the carburetor is resting against the throttle stop screw. Adjust the stop screw

to

obtain a setting of

55

?

1

hertz

(45.0

-t

1

hz on

50

hertz units).

Turn the idle adjustment screw inward until voltage and frequency drop and engine begins

to

run rough or starts hunting. Back out idle adjustment screw as required for smoothest operation without hunting. Recheck setting in step

5.

Release the governor linkage and observe the stability

of

the set. Set the voltage and frequency and

adjust the sensitivity

of

the governor as specified in

Governorin this section. Add and remove a full load

several times

to

make certain the set does not bog

down or hunt.

-

FS-1759

FIGURE

6-9.

MIXTURE SCREW ADJUSTMENT

6-1

3

Carburetor Overhaul

Carburetion problems not corrected by mixture or float

adjustments are usually a result of gummed-up fuel

passages or worn internal parts. The most effective solution is a complete carburetor overhaul.

In general, overhauling a carburetor consists

of

complete disassembly, a thorough cleaning, and replacement of worn parts. Carburetor repair kits are available that supply new gaskets and replacements for those parts most subject to wear.

General instructionsfor overhauling a carburetor areas follows: Carefully note the position while removing all parts to ensure correct placement when reassembling. Read through all the instructions before beginning for a better understanding of the procedures involved. Carburetor components are shown in Figure 6-10.

Removaland Disassembly:

Remove the carburetor and intake manifold assembly asspecified in the Carburetor and Intake Manifold Assembly in this section. Remove the carburetor from the intake manifold and disassemble using the following procedure.

1.

2.

Remove the main and idle mixture screw

assemblies. Separate the lower section of the carburetor.

Remove the float chamber by removing the bolt from the bottom

of

the carburetor.

V

CHOKE

PLATE

PILOT

JET

SCREW

/

3.

Carefully note position of the float assembly parts, then slideout retaining pin and remove thefloat and needle valve.

4.

Unscrew and remove the main nozzle.

Do

not remove the choke

or

throttle plates, shafts, arms

or

governor

link bushing unless they are defective.

Clean

and

Repair:

When the carburetor

is

completely

disassembled, clean and repair using the following

procedure.

1.

2.

3.

4.

5.

6.

Soak all metal components not replaced by repair

kit in carburetor cleaner.

Do

not soak non-metal floats or other non-metal parts. Follow the cleaner manufacturer's recommendations.

Clean all carbon from the carburetor bore, especially where the throttle and choke plates seat. Be careful not to plug the idle or main fuel ports.

Blow

out all passages with compressed air. Avoid using wire or other objects for cleaning that might increase the size

of

critical passages.

Check the condition

of

any needle valve and

replace

if

damaged (Figure 6-1

1).

Replace float

if

loaded with fuel or damaged. Check the choke and throttle shafts for excessive

play in their bore and replace

if

necessary.

Replace old components with new parts included in repair kit.

THROTTLE

IDLE

SCREV-

SCREW

\?

FUEL BOWL GASKET

FUEL

4

BOWL

L-74

WASHER

-b@

O-RING

-ik

BOLT

/-

NT

THROTTLE

PLATE

FS-176D

CAP

SPRING

PLATE

FIGURE

6-10,

CARBURETOR OVERHAUL

6-1

4

.

Reassembly and Installation:

When the carburetor

parts are clean and dry, reassemble using the following

procedure.

1.

If

removed during overhaul, slide in thethrottle shaft and install the throttle plate using new screws, if necessary. Before tightening the screws, the throttle

plate must be centered in the bore.

To

do

so,

remove the throttle stop screw and completely close the throttle lever. Seat the plate by gently pressing with fingers into place, then tighten screws. Install the

choke shaft and plate in the same manor.

OCCUR

HERE

II

FS-1483.2

FIGURE

6-11.

MIXTURE NEEDLE INSPECTION

2.

Install idle mixture screw assembly. Turn in screw

until lightly seated and then out the number of turns

specified in Table

6-2.

Forcing the mixture adjustment

[BCAUTIONI

screws tight will damage the needle and seat. Turn in only until light tension is felt.

3.

Install needle valve and seat, fuel bowl gasket and

float

assembly. Make sure all clips and springs are properly placed and the float moves freely without binding (See Figure

6-1

2).

POSITION

HOOK

UNDER

TAB

ON

FLOAT

4.

Invert the float and needle valve assembly and check float level by measuring between the float

and

carburetor

at

the

point

shown

in

Figure

6-13.

The

full

weight

of

the float should

be

resting on the

needle valve and spring. The correct distance is

specified in Table

6-2.

If the setting is incorrect, remove float and bend tab to adjust. Bend the float only at the point indicated.

Attempting

adjustments

with

dhe

laCAUTlONI

float assembly instal/@

can

dam-

age the inlet needle and

seat

Remove float assembly

before

making

adjustments.

FS-17E-2

FIGURE 6-13. FLOAT LEVEL

5.

Install float bowl and main mixture screw assembly. Turn screw in until lightly seated and then turn out the number

of

turns specified in Table

6-2.

Forcing the mixture adjustment screws tight will damage the

needle and seat.

Turn

in

only until light tension can

be felt.

6.

When carburetor

is

installed on set, make final

adjustments

to

mixture screws as described in Car-

buretor Mixture Screw Adjustments section.

FS-1761

FIGURE

6-12.

FLOAT INSTALLATION

6-1

5

Choke

The choke consists of a bi-metal, spiral strip, electric heating element, and choke pulloff diaphragm. The bimetal coil is connected to the choke shaft and holds the

choke plate nearly closed when the engine is cold.

When the engine starts, vacuum from the intake mani-

fold causes the pulloff diaphragm to pull in and partially open the choke. As the engine continues to run, electric current is supplied

to

the heating element. Heatfrom the element causes the bi-metal strip to coil. The coiling action of the bi-metal strip turns the choke

shaft

and

gradually opens the choke plate. Heat from the element

keeps the choke open while the engine is running.

The choke gets very hot during nor-

-1

mal operation and can cause severe

burns if touched.

Do

not

touch the choke assembly

during

and

after set operation.

Allow

the set to cool

down

before working on the choke assembly.

If

the engine starts but runs roughly and blowsout black smoke after a minute or two of operation, the choke is set

too

rich.

If

the engine starts but sputters or stops

before it warms up, the choke is set

too

lean.

Choke Adjustment:

An adjustment screw

is

mounted on

the bottom

of

the choke assembly (see Figure

6-14)

for making choke setting adjustments. Turn the adjustment screw clockwise to lean the system and counterclockwise

to

increase richness.

If

the choke has been replaced

or

is way out of adjust-

ment, use the following procedures toestablish an initial

choke setting.

Allow the generator set

to

cool down (an ambient

temperature of approxi'mately

75°F

[24OC]

is

required) before making initial setting. Move the choke lever back and forth

to

check for

free movement. Verify that choke does not bind

or

stick. Slowly rotate the adjustment screw on the bottom of

the choke assembly

so

that the choke lever

is

held in

the center of its travel.

Move the choke lever back and forth to check for smooth operation. Choke lever should return automatically

to

the center position when released from

the open position without sticking

or

binding.

FS-1762

FIGURE

6-14. CHOKE ASSEMBLY

Choke Replacement:

If

the choke fails to open,

check

to

see

if

the heating element

is

working. The

heating element cover should become

hot

after a

few minutes of operation.

If

the element cover does not get hot, start the set and then use an AC voltmeter to check for voltage (approximately

20

VAC) at

the element cover terminals.

If

voltage is not pres-

ent, check for opens or shorts in the control wiring.

If

the voltage is presentat the heating element cover

terminals, stop the set and remove the heating ele-

ment cover. Inspect the heating element and replace

if

burned out or broken. Also inspect the bi-metal spiral strip and replace if damaged, deteriorated,

or

dragging in the housing.

When installing a new bi-metal strip, maintain the

original direction

of

spiral (see Figure

6-15).

The outer tab must point in a clockwise direction. Make sure the coil rests squarely in the housing and the

inner end of the coil engages the

slot

in the choke shaft. When installing the element cover, makesure the slotted tang on the cover engages the bi-metal strip.

CLOCKWISE

\

4

\.

,

OUTER

TAB

FS-1606-1

FIGURE

6-15. BI-METAL SPIRAL

STRIP

6-1

6

Choke Pulloft Diaphragm Adjustments:The choke pull-

off

diaphragm Partially opens the choke Plate following

engine

startup.

This

helps

prevent flooding and pro-

vides for smoother engine operation as the set

is

warm-

ing up. Use the following procedure to adjust.

Fuel

Pump

An electric fuel pump is used

to

supply fuel to the car-

buretor.

If

the

pump malfunctions

or

insufficient fuel

delivery is suspected, use the following procedures

to

test the fuel pump.

1.

2.

3.

4.

5.

Disconnect the diaphragm hose from the rear side

of the intake manifold and apply

1

to 2 inches (25.4

to

50.8

mm) Hg vacuum

to

the diaphragm. Diaphragm stem should pull in and remain in while vacuum is applied.

Apply finger pressure lightlyagainstthe choke lever

to

take up the free play

in

the pulloff linkage (see

Figure

6-16).

Check linkage alignment (as viewed from the top) of diaphragm stem, pulloff linkage, and choke linkage. Correct alignment

as

required

to

obtain one-half

travel

at

choke lever.

Move the choke lever back and forth

to

check for free movement. Verify that choke does not bind or stick.

Remove vacuum supply and reconnect the diaphragm hose

to

rear side of intake manifold.

DIAPHRAGC

HOSE

h

%

CHOKE

LINKAGE

LEVER

Do not subsfitute automotive type

@@@&I

electric fuel pumps for standard

Onan

supplied

electric fuel pumps. The output pres-

sure is much higher andcan cause carburetor flooding

or

fuel leakage, creating a fire hazard.

Fuel Pump Test: Test the fuel pump by checking the pump outlet pressure as follows:

1.

Remove fuel line from carburetor inlet and install a

pressure gauge.

2.

Press start switch and hold it for several seconds, until pressure reading is constant.

3. The pressure reading for a good pump should fall within

3-1

12 to 5 psi

(1

7.2

to 34.4 kPa). The pressure

should stay constant or drop

off

very slowly.

If

pressure reading is below

3

112

psi (17.2 kPa),

replace fuel pump.

If

pressure reading is at zero, stop engine cranking and check electrical connections. Press the Start switch and recheck pressure reading.

There are no serviceable components in the fuel pump. Replace complete fuel pump assembly

if

defective.

FSlW

FIGURE

6-16.

CHOKE

PULLOFF DIAPHRAGM

6-1

7

LPG

FUEL

SYSTEM

The LPG-fueled models use a low-pressure vapor withdrawal system that must be properly adjusted and

be in good working condition. Components unique

to

the fuel system are:

Demand Regulator with Automatic Priming

Solenoid

0

LPG Carburetor

0

Fuel Solenoid

Special precautions must be taken to avoid releasing large quantities of highly flammable

LP

gas when servic-

ing the fuel system. Use the LP gas purging procedure

described in the

Preparing

to

Service

section

to

purge the fuel system of LP gas before servicing any fuel system components.

The fuel supply line pressure to the demand regulator must be in the range

of

6

to

B

ounces per square inch

(10

to

14

inches

of

water

column).

The fuel supply line from the primary regulator to the generator set fuel system components must be dedi-

cated

to

the generator set only and not shared with any

appliances.

[-I

LP gas presents the hazard of fire

or

explosion and

it

is poisonous. These

hazards can result in severe personal injury

or

death. If flameout occurs with an unvented appliance, LP gas can accumulate inside the vehicle and create a safety hazard. If the generator set tuel supply line

is

shared

with any appliance, do not continue with any further

service procedures. Correct as necessary to comply

with applicable codes before continuing service

work.

Demand

Regulator with Automatic Priming

Solenoid

The demand regulator is designed for low pressure vaporized fuel. An automatic priming solenoid allows fuel to pass through the regulator during cranking. Ser-

vice

is

limited to replacing the complete assembly

if

it malfunctions. The regulator assembly is usually not the cause

of

engine performance problems.

All

other possi-

ble causes should be checked before replacing the

regulator assembly. Refer to Figure

6-17.

The regulator should be periodically inspected for fuel leakage past the valve seat and to make sure that the vent is clean.

The priming solenoid can be bench tested by connect-

ing battery positive

(B+)

to

the orange lead and battery

negative

(B-)

to the green lead. The solenoid should

energize and press in on the regulator diaphragm. The priming solenoid can be adjusted by manually hold-

ing in the plunger disk and then rotating the adjustment dial clockwise

to

increase fuel flow or counterclockwise

to decrease fuel flow. Refer

to

Figure

6-18.

OUTLET

D

I

AUTOMATIC

PRIMING

I

VENT

ADJUSTMENT

SCREW

Fs-1848

FIGURE

6-17.

DEMAND

REGULATOR

WITH

AUTOMATIC

PRIMING

SOLENOID

NOTCH ON PLUNGER

ZERO MARK

ON

DIAL

FS-1849

At this position there

is

no

iuel

flow

when

the

Aulo

Prime is energized.

To

start and increase

iuel flow.

turn

dial clockwise while manually

depressing plunger.

FIGURE

6-18.

AUTOMATIC

PRIMING

SOLENOID

6-1

8

.

Regulator

Lock-off

Adjustment

The

regulator

lock-off

setting

is

used

to

set the valve opening pressure. The lock-off can be checked and adjusted as follows:

1.

Connect the regulator inlet (Figure

2)

to a source

of

air pressure regulated to

6

02.

(1

1

inches of water

column).

2.

Connect

a“T”

in

the balance line hose and connect

one leg of the

“T”

to an incline monometer that

reads from

0

to2 inches

of

water column. Connect a

hose to the other side of the

“T”.

3.

Put a soap bubble over the outlet opening of the regulator. Lightly blow into the hose connected to

the

“T”

in the balance line. Slowly apply pressure until the soap bubble continues to grow because of air flowing through the regulator. Approximately

0.25

to

0.35

inchesof water column should causeair to flow through the regulator. (When air is first blown into the balance line the soap bubble may enlarge due

to

diaphragm movement, this is not an indica-

tion that air is flowing through the regulator.

4.

If

more than

0.35

inches of water column pressure is

required

to

induce flow, loosen the lock nut on the

1

/4-28

lock-off adjusting screw, back out the screw

until air will flow in the

0.25

to

0.35

water column

pressure range.

If

air flows through the regulator without any pressure being applied to the balance line, the lock off adjustment screw must be turned in

to

increase spring pressure. When the proper set-

ting

is

achieved, hold the lock

off

adjusting screw in

position and tighten the locking nut. If adjustments

do not resolve problems see step

5.

If

the inlet pressure is

too

high or

if

there is dirt on the

regulator inlet seat, the regulator will flow air even

though the adjusting screw is turned all the way in. The regulatorshould not bedisassembled or repairs attempted by anyone except the equipment manufacturer’s factory trained service technicians.

Fuel Solenoid Valve

The fuel solenoid valve (Figure

6-19)

provides a

positive fuel shutoff whenever the generator set

is

stopped. The solenoid must be energized before fuel will flow

to

the regulator. Service is limited to

replacing the complete valve assembly

if

it

does not operate properly. The fuel solenoid can be bench tested by connecting battery positive

(B+)

to

the top

terminal and battery negative

(B-)

to

the grounded terminal. The plunger assembly should withdraw and open the valve when the solenoid is energized.

Replace the solenoid valve if

it

does not operate

properly.

I

U

FS-1850

FIGURE

6-19.

FUEL

SOLENOID

VALVE

6-1

9

LPG

Carburetor

LP-gas carburetors have three adjustment screws that must be properly set for satisfactory operation. The

throttle stop screw controls how much the throttle plate

remains open when the throttle is pulled back

to

the closed position. The idle adjustment screw controls the fuel mixture when the set is operating at no load. The

main adjustment screw controls the fuel mixture when

the set is operating at full load.

No

other adjustments are

required with an LP-gas carburetor since there are no

float or choke adjustments.

Carburetor Mixture Screw Adjustments

Mixture screws should not be adjusted until the ignition system, governor, and other fuel system components have been checked for correct operation.

If

thecarbure-

tor is totally out of adjustment, turn the mixture screws in

until lightly seated. Fora preliminary adjustment turn the main adjustment screw out

4

to 5 turns and the idle

adjustment screw out 2 to

3

turns.

ACAUT~ON

Forcing the mixture adjustment

Ll.3

screws tight will damage the needle

and seat. Turn in only until light tension can be felt.

Start the engine and allow it to run for about

15

minutes at half load. Figure 6-20 shows the location of the adjustment screws. Use the following procedure to adjust:

1.

Stop the set and connect a voltmeter, frequency meter, and load bank

to

the generator output leads.

2.

Start the generator set and apply a full load. Verify that the frequency

is

within

60 f 0.5

Hz

(50

f

1

on

50

Hz

units) and adjust the governor speed adjustment

nut if necessary to obtain required frequency.

3.

Turn the main adjustment screw inward until voltage or frequency drops and then outward until voltage or frequency drops again. Set the main adjustment screw at the point where thevoltageand frequency are highest.

4.

Remove the load and verify that frequency

is

within

62.5

f

0.5

Hz (52

f

0.5

on

50

Hz

units). Adjust

governor speed adjustment nut

if

necessary

to

obtain required frequency.

THROllLE STOP

-

ADJUSTMENT

SCREW

M-1878

FIGURE

6-20.

LPG

CARBURETOR ADJUSTMENTS

5.

Turn the idle adjustment screw inward until voltage

and frequency drops and engine begins to run rough

or

starts hunting. Back out idle adjustment

screw until engine runs smoothly without hunting.

6. Pull the governor linkage toward the front of the set

so

that the throttle lever on the carburetor is resting against the throttle stop screw. Adjust the stop screw to obtain a setting of

55

f

1

Hz

(45

f

1

Hz

on

50

Hz

units).

7.

Release the governor linkage and observe the stability

of

the set. Set the voltage and frequency and

adjust the sensitivity of the governor as specified in

Governor

in this section. Add and remove a half load

several times

to

make certain the set does not bog

down or hunt.

Carburetor problems not corrected by mixture adjustments may be caused by dirt in fuel passages

or

worn internal parts. Under normal conditions, the carburetor should seldom require cleaning since LP-gas vaporizes completely before reaching the carburetor and leaves no residue. However, a bad fuel supply may allow dirt or oil to collect in the carburetor. This may require that the carburetor be cleaned

to

restore satisfactory operation.

Cleaning the carburetor includes complete disassem-

bly, thorough cleaning, and replacement

of

worn parts

and gaskets.

6-20

ELECTRIC STARTER

A

12-volt electric starter with negative ground

is

used

for cranking the generator set. When the starter is ener-

gized, an inertial engagement system causes thestarter pinion gear to engage the

ring

gear on the fan hub

assembly.

As

the starter spins, the starter pinion gear drives the ring gear causing the generator set to crank. Because the starter

is

an integral part

of

the set control system, check the complete control before servicing the starter. Use the following procedures to disassemble,

inspect, and assemble the starter.

b

It

is

necessary to remove the generator set from the

vehicle before the starter can be serviced. Refer

to

Set

Removal instructions in section

5.

Disassembly

1.

2.

3.

4.

5.

Verify that the generator set starting battery

has

been disconnected, negative

(-)

cable first, before

proceeding. Remove the generator set outer hous-

ing

and disconnect the positive

(+)

cable from the

starter lug.

Remove the starter mounting bolts. Remove the rear support mounting nut and loosen the rear starter support bracket mounting bolt.

Carefully disengage the starter from the end bell.

Use a

1

/8

to

5/32

inch nail set to remove the roll pin

from

the armature shaft. Remove the return spring, gear and clutch assembly as required. When reassembling always use a new roll pin. See Figure

Remove the starter through bolts and carefully separate the brush end cap housing and armature

assembly.

6-21.

THROUGH

BOLTS

w

STARTER

5/32"

TO

1

Is"

NAIL

SET

SUPPORT PLASflC

RETAINER WH

A

WSE

OR

OTHER

SOUD

SURFACE

,I

'I

USE CARE NOT

TO

HAVE

SPRING

RETURN

RETAINER 8 SUPPORT

WHEN

DRMNG

OUT

ROLL

'LEG-

BETWEEN

THE

Pmnc

I

I I

I

supwRTl

Es-1609-1

FIGURE

6-21.

DRIVING ROLL

OUT

6-21

TORQUETO

5-10

IN-LBS

(57

-

1.13

Nom)

RQUE TO

25-30

IN-LBS

(2.8

-

3.4

Nom)

IMPORTANTI THIS

INSULATED

SHUNT

MUST

BE

ROUTED

THRU

UNINSULATED

SHUNT

AS

SHOWN

TO

PRNENT

WITH

COMMUTATOR

IN

FINAL

A

NEGATIVE

BRUSH

__

TERM~NAC

ES-16ll.2

FIGURE

6-22.

BRUSH

ENDCAP

Assembly

6.

Make sure all brush wires are clear

of

commutator

1.

2.

3.

4.

5.

Wipe

off

all dirt and oil from starter components

using a clean cloth or blow

off

dirt with filtered, low

pressure compressed air.

71

Oil

on

armature will damage

*CAUT’oN

starter.

Do

not immerse bearings in cleaning fluid. Use a brush dipped in clean engine oil

for

removing dirt from bearings. Avoid

getting oil on brushes

or

commutator.

Push negative brush terminals over through-bolt holes on brush endcap. See Figure 6-22.

Insert positive brush stud into hole and torque to 25-30 in-lb (2.8

-

3.4 Nom).

Place brush springs into brush holders. Insert brush tabs into spring ends and slide brushes into brush holders in endcap. Be sure all brush wires are facing up.

Place washer on commutator end

of

shaft and put

armature into brush endcap. Push the four brushes

toward commutator, making sure springs are prop-

erly positioned on brushes.

Replacement brushes are supplied preassernbled in the endcap. Remove brush retainers alter installing armatures.

and that uninsulated portions of insulated wires do not touch inside diameter

of

housing. Uninsulated portions of wires must also not touch adjacent brush boxes.

7.

Place magnetic housing over armature. Use a nut driver over the end of shaft

to

hold down armature

and endcap.

8.

Place spring washer and flat washer on shaft as shown in Figure 6-26.

9.

Place mounting bracket on motor with through-bolt “lead-ins” to the inside of motor.The “flat” near one mounting hole should line up with the positive stud on end cap

so

through-bolt will line up.

10.

Insert the through-bolts and torque to 35-45 in-lb (3.4-5 Nom).

11.

Wipedustfrom

helixandgearandapplyalight

coat

of

GE

Versilube 322-L on outside diameter of helix, inside diameter of gear and unchamfered end of gear. Place clutch and helix assembly on motor shaft with flats engaged in clutch hole.

Testing Armature

for

Grounds:

Touch one ohmmeter

lead to a commutator bar and then touch the other lead

to

armature shaft and core laminations. A low resistance reading indicates a grounded armature. Replace grounded armature with a new part. See Figure

6-23.

ES-1614

FIGURE

6-23.

TESTING

ARMATURE

FOR

GROUNDS

Testing for

Shorts:Use a growler (Figure

6-24)for

locat-

ing shorts in the armature. Place armature in growler

and hold a thin steel blade (e.g. hacksaw blade) parallel

to

the core and just above the armature while slowly

rotating armature in growler.

A

shorted armature will cause the blade to vibrate and be attracted to the core. Replace a shorted armature with a new part.

.

ES-1615

FIGURE

6-24.

TESTING

ARMATURE

FOR

SHORTS

Testing for Opens:

Touch one ohmmeter lead to a

commutator bar and then systematically touch the other lead

to

each

of

the remaining commutator bars. A high resistance reading indicates an open circuit between the commutator bars and armature windings. Replace an

open

armature with a new part.

Brush Inspection:

Measure brushes (Figure

6-25)

and

replace

if

worn less than

0.425

(1 1

mm).

0.315

INCH

NEW

0.472

INCH

ES-1768

FIGURE

6-25.

BRUSH

INSPECTION

6-23

WASHER

METAL

\

SPRING

RETAINER

CLUTCH

&

FIATWASHER

1

ASSEMBLY

1

ES-1613-1

FIGURE

6-26.

STARTER

ASSEMBLY

12.

If

Return Spring

is

Unassembled:

A.

Place

1-1

/16

inch

O.D.

washer over end

of

shaft. See Figure

6-26.

8.

With chamfered sideof shaft hole up, place plastic retainer on shaft and line up hole with hole in shaft.

C. Support the plastic retainer with a vise

or

other

solid surface. Using a

5/32

to

118

inch nail set

and hammer, drive in a new roll pin. The pin

should

be driven in about 1/10th

of

an inch

(2.5

mm)

from the edge

of

the plastic retainer or

so

it

is

evenly spaced from each side.

D.

Place spring cover over top

of

plastic retainer,

then the return spring on top of the retainer.

E.

With washer placed over point

of

plastic

retainer, push metal retainer into hole of plastic

retainer as far as

it

will go.

13.

Carefully mount the starter on the end bell and tighten the mounting bolts and rear support bracket mounting

bolt

and nut

to

the specified torque.

14.

Connect the positive

(+)

cable

to

the starter lug

terminal.

15. Mount outer housing on the generator set and install set into vehicle.

16. Reconnect generator set starting battery, negative

(-)

cable last.

6-24

Section

7.

Control

INTRODUCTION

The control system includes all functions that relate to starting, monitoring

for

fault conditions, instrumentation, battery charging, and stopping. This section covers how the control operates, where the components are located, and basic troubleshooting procedures.

CONTROL DESCRIPTION

The generator set control consists

of

the following

components:

0

Panel mounted Start/Stop Switch (Sl)

0

Start Solenoid

(Kl)

0

Start Disconnect Relay (K2)

0

Control Fuses (F1 & F2)

0

Battery Charge Resistor (Rl) Shutdown Circuit (K3, K4, K5)*

0

Optional Remote Start Control

Start/Stop Switch

The startlstop switch (Sl) isasingle pole, double throw

(SPDT), rocker-typeswitch used for starting or stopping

the generator set. Placing the switch in either the start or

stop position will initiate the appropriate control func-

tion. The switch will automatically return to the center

(Run) position when released.The switch is mounted on the control panel and is removable for service replacement.

Start Solenoid

The start solenoid (Kl) is used for opening and closing the circuit between the starter motor and the battery.

The start solenoid is used because of the high current

load imposed during starting.The solenoid is made with

heavy duty contacts to withstand high current draw during start-up. The start solenoid is located on the left side of the unit near the base and is not serviceable through the removable access cover.

Start Disconnect Relay

The start disconnect relay

(K2)

energizes once the

generator set output reaches

70

volts AC. This opens the circuit between the start solenoid (Kl) and the battery and causes the starter motor

(Bl)

to stop cranking.

The start disconnect relay also closes the circuit between

the battery and the fuel pump (E2)** and the K3* relay during generator set operation. The start disconnect relay is located on the control panel and is removable for service replacement.

Control

Fuses

Provide protection for the control

box

wiring and remote

wiring from short circuit or other overload. The cranking

fuse provides protection during start-up, and the run-

ning fuse provides protection while the generator set is running. The control fuses are mounted on the front of

the control panel and are removable for service

replacement.

Battery Charge Resistor

The battery charge resistor limits the battery charge rate

to

no more than 1 ampere. The resistor mounts on top of

the generator and is removable for service replacement.

Shutdown Circuit*

The shutdown circuit consists of two relays (K3,

K5)

and

a solenoid

(K4).

These components work together to prevent the generator set from running once the start/ stop switch is placed in the stop position.

Both relays are mounted

to

the back side of the set on the generator end. The solenoid is mounted on top the engine. These components are removable for service

replacement.

Optional Remote Start/Stop Control

The remote start/stop control is an optional accessory that allows the generator set

to

be started, monitored,

and stopped from a remote location. The deluxe control

includes a running time meter and a battery condition meter. Remote control panels are usually mounted inside the vehicle.

CONTROL OPERATION

-

GASOLINE FUELED

The following section covers the control operation. The

schematic diagram shown in Figure 7-1 can be used to help follow the circuit description. Always refer

to

the

specific wiring diagram that corresponds

to

the model and spec number of the generator set when troubleshooting.

"Gasoline sets only

**E2 is the fuel pump on gasoline sets and the fuel

solenoid on LPG sets.

7-1

Starting

Placing the start/stop switch (Sl) in the start position connects battery negative (B-) to the start relay coil (Kl).

This energizes the start relay, which closes the K1-

1

/K1-2 relay contacts that connect battery positive (B+)

to the starter motor (Bl).

It

also connects B+ to the fuel pump (E2) and the K3 relay, through fuse F2 and diode CR1. (The fuel pump is energized through diode

CR3,

used to bypass ballast resistor

R2,

on initial production

sets. CR3 and

R2

may not be used on later production sets. Battery positive (B+) is also supplied to the voltage regulator (pin

7),

for the generator field winding, through

the start disconnect relay (K2) normally closed contacts

(K2-2/ K2-6).

Connecting battery positive (B+)

as

described produces

the following control responses:

0

Flashes the generator field winding to ensure that there is adequate residual magnetism to inducevoltage buildup.

0

Energizes the starter motor

(81).

0

Energizes the fuel pump (E2) which begins pumping

0

Energizes relay K3.

fuel to the carburetor.

Closing the start solenoid (Kl) contacts connects the battery positive

(B+)

to the starter motor, which begins to

crank the engine to initiate starting.

Starter Lockout-Run

As the engine comes up to speed, the power output from

the generator is applied to the start disconnect relay (K2)

and causes it to energize. Engergizing the K2 relay opens the K2-1/K2-5 and K2-2/K2-6 contacts and closes the K2-3/K2-5 contacts. This produces the following control responses:

0

Opening the K2-1 /K2-5 contacts disconnects

B+

from the start solenoid (Kl) de-energizing it and

causing the

K1-1

/K1-2 contacts to open. This dis-

connects B+ from the start motor (Bl).

0

Opening the K2-2/K2-6 contacts disconnects

B+

from the voltage regulator

0

Closing the K2-3/K2-5 contacts applies B+ to the

fuel pump

(E2)

and to the K3 relay, through fuse

F1,

providing fuel flow to the carburetor and ignition

voltage from the magneto assembly

(G2)

to the

spark plug (El).

As the engine begins to run, the start/stop switch should be released. The switch will automatically return to the center (Run) position and the engine will continue to run. The start disconnect relay (K2) will remain energized and the start solenoid (Kl) remains de-energized.

Charging Circuit

The charging circuit supplies voltage to the choke

heater element (Hl), which activates the heating element and opens the choke. The charging circuit also supplies generator battery charge voltage (20

f

2 volts)

that is rectified to DC by diode (CR2) and supplied

to

the

battery through the charge resistor

(Rl).

This charges

the battery at a variable rate

(1

ampere maximum) during set operation. The charge rate varies with the generator load and battery condition.

Stopping

Placing the start/stop switch

(SI)

in the stop position

energizes the K5 relay, which opens K5-301K5-87A

relay contacts.This removes B+from the fuel pump

(E2),

stopping fuel flow to the carburetor. B+ is also removed from relay K3, which causes the K3-30IK3-87A contacts

to

close and ground the output from the magneto

assembly

(G2).

Placing the start/stop switch in the stop position also energizes solenoid K4, which pushes against the governor arm causing it to close the throttle. Each

of

these actions work together to shut down the

generator set. As the generator output voltage drops, the start discon-

nect relay (K2) de-energizes, opening contacts K2-3/K2-5.

Diode CR2 prevents the battery from discharging through the generator windings when the set is not running.

7-2

CONTROL OPERATION

-

LPG

FUELED

Starting

Placing the start/stop switch (Sl) in the start position

connects battery negative

(B-)

to the start relay coil

(KI).

This energizes the start relay, which closes the

K1-

1

/K1-2 relay contacts that connect battery positive

(B+)

to

the starter motor

(61).

It

also connects

B+

to the K4

priming solenoid and

E2

fuel solenoid, through fuse

F2

and diode CRl. Battery positive (B+) is also supplied

to

the voltage regulator (pin

7),

for the generator field wind-

ing, through the start disconnect relay

(K2)

normally

closed contacts (K2-2/K2-6). Connecting battery positive

(B+)

as described produces

the following control responses:

Flashes the generator field winding

to

ensure that there is adequate residual magnetism to inducevoltage buildup.

0

Energizes the starter motor (Bl). Energizes the priming solenoid (E4) and the fuel

solenoid

(E2)

allowing fuel to flow

to

the carburetor.

Closing the start solenoid (Kl) contacts connects the battery positive (B+) to the starter motor, which begins to crank the engine to initiate starting.

Starter Lockout-Run

As

theengine comesup tospeed, the power outputfrom the generator is applied to the start disconnect relay (K2) and causes it to energize. Engergizing the K2 relay opens the K2-1/K2-5 and K2-2/K2-6 contacts and

closes

the K2-3/K2-5 contacts. This produces the

fol-

lowing control responses:

0

Opening the K2-2/K2-6 contacts disconnects

B+

from

the voltage regulator

0

Closing the

K2-3/K2-5

contacts applies

B+

to

the fuel solenoid (E2) through fuse F1, providing fuel flow

to

the carburetor.

As

the engine begins

to

run, the startlstop switch

should be released.Theswitch will automatically return

to

the center (Run) position and theengine will continue to run. The start disconnect relay (K2) will remain energized and the start solenoid (Kl) remains de-energized.

Charging Circuit

The charging circuit supplies generator battery charge voltage (20

f

2 volts) that is rectified to

DC

by diode (CR2) and supplied to the battery through the charge resistor

(Rl).

This charges the battery at a variable rate (1 ampere maximum) during set operation. The charge rate varies with the generator load and battery condition.

Stopping

Placing the start/stop switch (Sl) in the stop position energizes the K3 relay, which causes the K3-30/K3-87 contacts

to

close and ground the output from the mag-

neto assembly (G2) and stops the engine.

As

the generator output voltage drops, the start disconnect relay (K2) de-energizes, opening contacts K2-3/K2-5. This causes the E2 fuel solenoid

to

open

and stop fuel flow

to

the regulator.

Diode CR2 prevents the battery from discharging

through the generator windings when the set is not

running.

Opening the K2-1/K2-5 contacts disconnects

B+

from the start solenoid (Kl) de-energizing

it

and

causing the K1-1 /K1-2 contacts

to

open. This dis-

connects

B+

from the start motor (Bl) and the K4

priming solenoid.

7-3

BT

I

--p11-

RI

I

I__-

P2

-<

3

t----,

I----

K5

K4

K3

R2

Z

T1 s3 s2 s1

R1

P2 P1 M2 M1

K2

K1 H1 G2

G1

F1,FZ E2

El

DSl

CR3 CR2 CR1 CB1

c1

ET1 E1

A2

A1

Relay Solenoid Relay Resistor

-

Ballast

Splice

Ignition Coil Switch-Start/Stop Remote Switch-Low

Oil

Level Switch-Start/Stop Resistor-C harging Plug-Remote Plug-Voltage Regulator Meter-Total

Run

Time Meter-Battery Condition Start Disconnect Relay Start Solenoid Choke Magneto-Ignition Generator Fuse-SA Fuel Pump

Spark Plug Lamp-Remote Diode Diode

Diode

Circuit Breaker Capacitor

Battery

Starter

Motor

Deluxe Remote Control Standard Remote Control

*R2

and CR3 may not be used in

later production sets.

FIGURE 7-1.

SCHEMATIC

-

60

HERTZ

7-4

BTI

K3 K4

z

T1 s3

s2

s1 R1 P2

P1

M2

M1

K2

K1

G2

G1 Fl.F2

E2 El

DSl CR2 CR1 C

Bl

c1

BT1

B1 A2 A1

t

RELAY-IGNITION STOP

SOLENOID-PRIMING Splice

Ignition Coil Switch-StaWStop Remote Switch Low Oil Level

Switch-StarVStop Resistor-Charging

Plug-Remote Plug-Voltage Regulator Meter Total Run Time

Meter Battery Condition

Start

Disconnect Relay

Start

Solenoid

Magneto Ignition

Generator

Fuse FUEL SOLENOID

Spark Plug

Lamp Remote Diode Diode

Circuit Breaker Capacitor

Battery

Starter Motor

Deluxe Remote Control

Standard Remote Control

CR.?

R

II

KZ

G2

--

II

I

FIGURE

7-2.

LPG GENERATOR SET

SCHEMATIC

-

60

HERTZ

7-5

The troubleshooting guide is divided into six sections. After identifying the problem, refer to the guide for the possible

and

the

recommended

corrective

action.

CONTROL TROUBLESHOOTING

Use the following troubleshooting guide

to

help locate problems related to the control. Figure 7-2 shows the location of most of the control components. Refer

to

the

wiring diagram in Figures

8-1

or 8-2

for

location of wiring terminals.

TROUBLESHOOTING

THE

CONTROL

Many troubleshooting procedures present hazards which can result in severe personal injury

or

death. On/y qualifiedservice personnel with knowledge of fuels, electricity, andmachinery hazards

should perform service procedures. Review safety precautions on inside cover page.

TROUBLE

Engine Does Not Crank

POSSIBLE CAUSE

~~ ~~ ~

1.

If

engine cranks at set but not at

remote control panel, fault is

due

to:

a. open circuit in remote

b.

faulty remote start/stop switch

2.

If engine cranks at remote control panel but no at set, fault

is

due

to:

a. open circuit in set control b. faulty set control start/stop

control wiring

panel wiring

switch (Sl)

3.

Insufficient voltage for cranking due to:

a. battery not charged,

or

b.

terminal connections loose

or

c. insufficient battery cable size

dirty

4.

Control fuse

F1

is open.

5.

Start disconnect relay K2 defective.

6. Start solenoid K1 not energizing due

to:

a. Open circuit between K1

and K2

or

K1 and ground

b. defective

K1

relay

c. defective start/stop switch

7.

Defective starter (Bl)

CORRECTIVE ACTION

1

a. Check for continuity and correct

1

b. Replace remote control start/stop

if

circuit is open.

switch (S3).

2a. Check for continuity and correct

if

2b. Replace set control start/stop switch.

circuit is open.

3a. Check condition of battery and 3b. Clean and tighten all connections

3c. Increase cable size.

recharge or replace. at start solenoid (Kl), starter motor

(Bl),

and ground connections.

4.

Locate cause of overload and correct as required. Replace fuse.

5.

Check for continuity at normally closed contacts K2-1 /K2-5 and replace

if

defective.

6a. Check for continuity and correct

if

circuit is open. 6b. Replace K1 relay. 6c. Check start/stop switch and replace

if defective.

7.

Refer to electric starter section

for test and service procedures.

7-6

TROUBLESHOOTING THE CONTROL

(Continued)

*

Many troubleshooting procedures present hazards which can result in severe personal injury or

IBWAR"G/

death. Only qualified service personnel with knowledge

of

fuels, electricity, and machinery hazards

should perform service procedures. Review safely precautions on inside cover page.

TROUBLE

Engine Cranks But Does Not

Start

Engine Starts But Stops When Switch is Released

POSSIBLE

CAUSE

1.

Faulty ignition due to worn

or

fouled

spark plug or faulty plug wire.

Faulty magneto or ignition coil.

2.

Control fuse F2 is open.

3.

Faulty CR1 diode, (open).

4.

Faulty fuel system due to sticking

choke, faulty fuel pump

-

gasoline sets (faulty priming solenoid, fuel solenoid, or regulator

-

LPG sets) or carburetor mixture screws incorrectly adjusted.

due to:

a. low oil level b. faulty low oil level switch

5.

Low oil level switch (S2) is not open

6.*Defective K5 relay contacts

7.*K3 relay not energizing due to: a. open circuit to K3 relay coil

b.

faulty

K3

relay.

8.

Governor linkage or

*K4

solenoid

stuck or binding.

*Gasoline sets only

1.

Output voltage from generator not being supplied to control due to:

a. open circuit in wiring between

b.

no output voltage from generator

generator and control

2.

Start disconnect relay K2 not energizing due to:

a. open circuit to

K2

relay coil

b. faulty K2 relay

3.*Fuel pump not energized due to

faulty ballast resistor R2 (if used).

4.

Corroded slip rings.

5.

Defective voltage regulator.

"Gasoline sets only

CORRECTIVE ACTION

1.

Refer

to

Ignition System section for

test and service procedures.

2.

Locate cause

of

overload and correct as

required. Replace fuse.

3. Test

CRl

diode and replace if

defective.

4.

Refer to Fuel System section for test and service procedures.

5a. Check oil level and add oil

if

low.

5b. Replace oil level switch.

6.

Check normally-closed contacts K5-30/ K5-87A, replace relay if defective.

7a. Check for continuity and correct

if

circuit is open.

7b. Check

K3

relay coil

(85

f5

ohms) and

contacts, replace

if

defective.

8.

Check for free movement of governor arm and solenoid. Repair as necessary.

la. Check for continuity and correct

if

circuit is open.

1

b.

Refer to Generator section for test and service procedures.

2a. Check for continuity and correct

if

circuit

is

open

2b.

Test K2 relay and replace

if

defective.

3. Check resistance of ballast resistor R2 for approximately 1.2 ohms and replace

if

defective. (R2

is

not used in

later production sets.)

4.

Refer to

Generator

section for

slip ring service.

5.

Refer to

Generator

section for voltage

regulator test.

7-7

TROUBLESHOOTING THE CONTROL

(Continued)

Many troubleshooting procedures present hazards which can result in severe personal injury or

k%@@%l

death. Only qualifiedservice personnel with knowledge of fuels, electricity, andmachinery hazards

should perform service procedures. Review safety precautions on inside cover page.

I

TROUBLE

Engine Starts and Runs, Then

Stops,

Set Restarts Immediately or Set Restarts After Cooling Down

Low Battery

POSSIBLE

CAUSE

I.

Fuel level is low or oil level is low.

!.*Faulty choke operation due

to

sticking choke linkage, incorrect choke adjustment, open circuit in wiring between

choke heater and generator, or

defective choke heater.

3.*Vapor lock due

to:

a.high ambient air temperature b.faulty fuel pump

4.

Contaminated or incorrect fuel.

*Gasoline sets only

1.

Weak or discharged battery.

Generator set charger will not recharge a battery that is in a very low state of charge.

2. Load connected to battery while set is turned

off.

3. Disconnect the negative

(-)

battery cable at the battery and remove lead marked F1-1

to

CR2-C from control fuse

F1

terminal

1.

Connect a DC

ammeter and

a

5-ampere fuse

in series between control fuse

F1,

terminal 1, and the disconnected

lead marked F1-1

to

CR2-C.

Reconnect battery negative

(-)

cable. With set running, the ammeter should read between

0

to 1 ampere.

If

meter shows battery is discharging,

fault is due

to:

a. defective generator charge

winding

b.

defective diode CR2

c. defective resistor

R1

~

CORRECTIVE ACTION

1.

Check fuel and oil level and refill as necessary.

2.

Refer to Fuel System section for

testing and service procedures.

3a. Remove any objects or debris that

may restrict airflow.

3b.

Refer

to

Fuel System section for

testing and service procedures.

4.

Refill tank with fresh fuel.

1.

Connect a separate battery charger to bring battery up to full charge.

2.

Turn

off

load.

3a. Refer to Generator section

for

3b. Test CR2 diode and replace

if

3c. Test resistor

R1

and replace

if

testing and service.

defective. defective.

7-8

TROUBLESHOOTING THE CONTROL (Continued)

Many troubleshooting procedures present hazards which can result in severe personal injury or

-1

death. Only qualified service personnel with knowledge of fuels, electricity, andmachineryhazards

should perform service procedures. Review

safety

precautions

on

inside cover page.

1

TROUBLE

Run Lamp, Time Meter,

or

Battery Condition Meter Inoperative

Generator Set Does Not Stop After Start/Stop Switch

Is

Pushed to

Off

Position

(Note:

Always

remove

load

a

few minutes

before stopping

to

allow set

to

cool

down.)

POSSIBLE CAUSE

1.

Open circuit between terminal

6

on remote connector plug and terminal

6

on remote start/stop

switch.

2.

Open circuit between ground terminals on lamp

or

meters

and terminal

1

on remote start/ stop switch and remote connector terminal

1.

3. If battery condition meter works but time meter does not operate, time meter is defective.

4. If time meter works but battery condition meter does not operate verify that jumper wire is connected between terminals

5

and 6 on remote start/stop switch. If jumper is in place, connect a voltmeter between the positive terminal on battery charge meter and ground. Use the following

to

determine

fault:

a.

If

reading equals battery

voltage minus

10

volts,

battery meter is defective

b.

if

reading does not equal

battery voltage minus

10

volts, zener diode in remote control is defective.

1.

Faulty set control start/stop switch

(SI)

2.*K5 relay not energizing due

to:

a. open circuit

to

K5 relay coil

b. faulty K5 relay

3.*K4 solenoid not energizing due a. open circuit

to

K4 solenoid

a. faulty K4 solenoid

to:

4.*K4 solenoid

out

of adjustment.

5.

Defective K3 relay contacts

*Gasoline sets only

CORRECTIVE ACTION

~~

1.

Check for continuity and correct if circuit is open.

2.

Check for continuity and correct if

circuit

is

open.

3. Replace time meter.

4a. Replace battery condition meter. 4b. Replace zener diode.

1.

Check start/stop switch and replace if defective.

2a. Check for continuity and correct

if

circuit is open.

2b. Check K5 relay coil

(85

rt5ohms) and

contacts, replace

if

defective.

3a. Check for continuity and correct

if

3b. Replace K4 solenoid.

circuit is open.

4. Adjust K4 solenoid mounting bracket

sc

solenoid causes governor arm to completely close throttle when energizr

5.

Gasoline-fueled sets: Check normallyclosed contacts K3-30/K3-87A, replacc relay

if

defective.

LPG fueled sets: Check K3 relay coil ai K3 normally-open contacts K3-30/K3-I replace relay if defective.

Nole:

A

ballast resistor

(R2)

is

used inline with the fuel pump to reduce the voltage toapproximately9volts. to increase pump life. During cranking,

the ballast resistor is bypassed through diode

CR3

for

low

voltage operation

of

the pump. Resistor

R2

and diode

CR3

are not used in later

production sets.

7-9

CONTROL

STARTISTOP

FUSES

SWITCH

5AMP

STOP

START

FIGURE

7-3.

CONTROL

COMPONENT LOCATIONS

7-1

0

Section

8.

Generator

b

INTRODUCTION

The

KV

generator set uses a 2-pole, revolving field,

generator design and an electronic voltage regulator.

All AC

load connections are made through generator

lead wires that connect directly to a customer supplied

junction box.

A

circuit breaker provides overcurrent

protection for the generator and also functions as an

on/off switch in the load circuit.

GENERATOR DESCRIPTION

The generator consists of the following major

components:

0

Stator and housing

0

Rotor

0

Electronic Voltage Regulator

0

Brushes Wiring Harness

The stator consists of a number

of

steel laminations stacked together, with three separate windings wound onto it in a torroidal fashion. Winding T1 -T2 is the main power winding that provides the voltage and current to operate the connected loads. Winding B1-62 is for battery charging and internal low voltage loads. Winding Q1 -Q2 is an excitation winding that provides power to

the voltage regulator. The stator mounts inside the

generator.

Rotor

The rotor consists of a number of laminations stacked together,

a

field winding wrapped around the lamina-

tions, a shaft through the laminations, molded slip rings

on the shaft and a bearing pressed on the shaft. The entire assembly is connected directly to the tapered engine crankshaft by means of a throughbolt. The rotor is supported

on

the other end by the endbell, which is

placed over the bearing and secured to the housing. The rotor field winding provides the rotating magnetic

field which in turn generates the voltage and current in the stator windings

to

power the connected loads. The

from the brushes through the slip rings and the field winding.

t

magnetic field is established by a

DC

current flowing

Generator

Cooling

Cooling airflow for the generator is provided by a centrifugal fan mounted on the shaft behind the bearing.

A

portion

of

the airflow from the fan is directed into the generator. Part of this air flows down the rotor cooling the rotor winding, and the rest flows over the stator windings cooling them.

Electronic Voltage Regulator

The electronic voltage regulator controls the output

of

the generator

so

that the voltage remains constant under any load condition.The electronic voltage regulator takes power from the excitation winding, rectifies it, and feeds it into the field winding through the brushes and slip rings. The regulator reads the output of the power winding and its circuitry decides how much current should be fed into the field winding to maintain the proper output at various load levels.

Brushes and Brush Block

The brush block isaone piece molded partthat mounts inside the endbell. There are two carbon brushes in the brush block which ride

on

the slip rings and provide the

means by which the controlled

DC

current from the regulator is conducted into and out of the rotor. Each brush is kept in contact with its slip ring by a spring mounted inside the brush block behind the brush. The spring exerts just the right amount of pressure to provide good contact and long brush life.

Wiring Harness

A

separate wiring harness is provided for connecting

the generator set to the

RV

electrical system. All lead wires are stranded copper wire to withstand vibration. The lead wires must be protected with flexible conduit which must be provided by the

RV

manufacturer or

generator set installer.

A

112

inch conduit elbow is provided to facilitate installation. The load wire conductor is black, the neutral conductor is white, and the ground conductor is green.

8-1

GENERATOR OPERATION

The schematic shown in Figure

8-1

is provided to help follow the generator operating descdplion. Always refer lo the specific schcmatic that correspondstothe modeland specnumberofthegenera-

lor

set when troubleshooting problems.

When the start/stop switch is placed in the start position, the rotor begins to turn and is momentarily connected to the battery.This providesa current in the rotor field winding which induces a voltage in thestator wind-

ings, in particular the excitation winding

Q1-Q2.

The regulator takes this voltage and rectifies it and feeds it back into the

rotor

which causes thevoltageto increase further. This process continues as the engine picks up speed. The voltage does not increase uncontrollably

because the regulator is connected to the power output leads

(L1

-E)

and constantly measures the output voltage and compares it to an internal reference voltage. When the output voltage exceeds the reference, the regulator causes the current in the rotor to decrease until the proper voltage is obtained.

During operation,

the

regulator is constantly monitoring

the output voltage. When additional load is applied

to

the generator, the output voltage starts to decrease. The regulator senses this decrease and increases the field current until the reference voltage and the output voltage match. Similarly, when the load is decreased the output voltage begins to increase, but is noticed by the regulator. In this case, the regulator decreases the amount of current to the field until the output voltage. again matches the reference voltage. In this manner the electronic voltage regulator keeps the voltage of the generator constant with varying load conditions.

1

GENERATOR TROUBLESHOOTING

Use the following troubleshooting guide to help locate problems related to the generator. Figure

8-3

shows the location of most of the generator components. Refer to the wiring diagram in Figures

8-1

and 8-2 for reference to the generator wiring. Always refer to the specific wiring diagram that corresponds to the model and spec number of the generator set when troubleshooting. The troubleshooting guide is divided into five sections. After

identifying the problem, refer to the guide for the possi-

ble cause and the recommended corrective action.

.

8-2

A2

AI

..

-.

Ir

'

--

Y

I

.'

'I

K5 K4 K3

R2

z

T1

s3

s2

s1

Rl P2

P1 M2 M1 K2

K1

H1 G2 G1 F1 ,F2

E2 El DS1 CR3 CR2 CR1 CB1

c1

BT1

B1

A2 A1

Relay Solenoid Relay Resistor

-

Ballast Splice Ignition Coil Switch-StartlStop Remote Switch-Low Oil Level Switch-StartIStop

Resistor-C harging Plug-Remote Plug-Voltage Regulator Meter-Total Run Time

Meter-Battery Condition Start Disconnect Relay Start Solenoid

Choke

Magneto-Ignition

Generator

Fuse-5A

Fuel Pump

Spark Plug

Lamp-Remote

Diode

Circuit Breaker

Capacitor

Battery

Starter Motor

Deluxe Remote Control Standard Remote Control

..

I

II

-.

-

I. I

+'

I

L-

4.

'R2

and

CR3

may

not

be used

in

later production sets

FIGURE

8-1.

GENERATOR

SET

WIRING DIAGRAM

-

60

HERTZ

8-3

K3 K4

z

T1 s3 52

s1

R1

P2 P1 M2

M1 K2 K1 G2

G1

F1,F2 E2

El DSl

CR2 CR1 CB1

c1

BT1

B1 A2 A1

,

I

FI-1

I

RELAY-IGNITION STOP SOLENOID-PRIMING

Splice Ignition Coil Switch-StartIStop Remote Switch

Low

Oil Level

Switch-StartlStop Resistor-Charging Plug-Remote Plug-Voltage Regulator Meter Total Run Time

Meter Battery Condition Start Disconnect Relay Start Solenoid Magneto Ignition

Generator Fuse

FUEL SOLENOID Spark Plug

Lamp Remote Diode Diode Circuit Breaker

Capacitor Battery Starter Motor Deluxe Remote Control Standard Remote Control

/

r,

I

'-

I I

I

FIGURE

8-2.

LPG

GENERATOR SET WIRING DIAGRAM

-

60

HERTZ

8-4

TROUBLESHOOTING THE GENERATOR

Many

troubleshooting procedures

present

hazards

which

can result

in

severe

personal

injury

or

death. Only qualified service personnel with knowledge

of

fuels, electricity, and machinery hazards

should perform service procedures. Review safety precautions on inside cover page.

TROUBLE

No AC Output

voltage

Note: This

condition may

cause the generator set

to

stop

when the start

switch

is

released.

AC Output Voltage

Too

Low

POSSIBLE CAUSE

1.

Open circuit breaker

2.

Open circuit between brush block and regulator or start disconnect relay contacts

K2-2/K2-6

and

the regulator

3.

Brushes stuck in holder or not making good contact with slip rings

4.

Capacitor (Cl) shorted

5.

Faulty start disconnect relay

(K2)

6.

Open, grounded, or shorted rotor or stator.

7.

Faulty electronic voltage regulator

1.

Engine governor incorrectly

2.

Brushes worn or not making

adjusted

good contact with slip rings

3.

Jumper lead not making contact on voltage regulator terminals

1

and

5

CORRECTIVE ACTION

1.

Locate cause

of

overload and correct as required. Reset breaker.

2.

Check for continuity and correct

if

circuit is open.

3.

Release brushes

if

jammed in holder. Clean slip rings if dirty.

4.

Check capacitor and replace

if

defective.

5.

Check start disconnect relay

(K2)

normally closed contacts

K2-2/K2-6.

Replace

if

defective.

6.

Test each component for open, grounded, or shorted windings and replace

if

defective.

7.

If

other possible causes check

good, replace voltage regulator.

1.

Refer to

Governor

section

2.

Check length

of

brushes and

replace

if

worn excessively.

Clean or replace slip rings.

3.

Check for jumper lead in regulator connector terminals

1

and 5 and

correct

if

not attached.

8-5

TROUBLESHOOTING THE GENERATOR

Many troubleshooting procedures present hazards which can result in severe personal injury or

k%!!!%l

death. Only qualified service personne! with knowledge of fuels, electricity, andmachinery hazards

should perform service procedures. Review safety precautions on inside cover page.

AC Output Voltage

Too

High

Noisy Generator

I

1

I

benerator

Overheats

I

--

POSSIBLE

CAUSE

1.

Engine governor incorrectly adjusted.

2.

Faulty electronic voltage regulator

1.

Loose brush holder

2.

Worn generator end bearing

3. Rotor and stator rubbing a. varnish lumps

b.

rotor misaligned with

cran kshaft

together due

to:

1.

Generator overloaded due

to

defective circuit

breaker

2.

Airflow restricted due

to

dirt

or

debris covering vent openings in stator housing

3. Stator windings covered with oil or dirt

4.

Open, grounded, or shorted circuit in rotor or

stator

CORRECTIVE ACTION

1.

Refer

to

Governor

section.

2. Check output voltage, if voltage is over 135 on

120

volt units,

242 on 220 volt units,

or

264

on

240

volt

units, and frequency is correct, replace

the electronic voltage regulator.

1.

Tighten brush holder.

2. Replace end bearing.

3a. Check for varnish lumps

between rotor and stator and remove as required.

3b.

Follow

specified assembly

procedures

to

correct

rotor to crankshaft alignment.

1.

Replace circuit breaker.

Do

Not exceed specified

load when operating set.

2.

Clean away all dirt

or

debris

as required.

3.

Clean stator windings

4.

Test each component

for

open,

grounded,

or

shorted

windings

and replace

if

defective.

c

.

8-6

G-1111

\

SCROLL

HOUSING

FIGURE

8-3.

GENERATOR

8-7

GENERATOR SERVICE

This section covers generator disassembly and assem-

bly procedures.

Refer

to

Figure 8-3

to

identify

the

various generator components described in each subsection.

Generator

Disassembly

Use the following procedures to disassemble the

generator:

1.

2.

3.

4.

5.

6.

7.

Drain the engine

oil

while the generator set

is

still

mounted in the vehicle.

Hot oil can cause severe burns if

k&@!%l

spilled or splashed on skin.

Keep hands clear when removing oil drain plug and

wear protective clothing.

Remove the generator set from the vehicle and place

it

on a sturdy workbench. Refer

to

Set Remo-

val (section

5)

for the recommended set removal

procedures.

The generator set is heavy and

lgWARNlNGl

can result in severe personal injury if dropped during removal. Use the recommended removal techniques and keep hands and

feet clear while removing mounting bolts.

Remove side mounting screws from enclosure

cover

and

lift

cover

off

set.

Disconnect the fuel line from the fuel pump. Plug

fuel lines

to

keep fuel from escaping.

Fuel presents the hazard

of

fire

or explosion which can cause

severe personal injury or death.

Do

not permit any flame, spark, pilot light, cigarette, or other ignition source near the generator set. Keep a type

ABC

fire

extinguisher nearby.

Remove the

K3

relay from the inlet baffle assembly

(Figure 7-2). Disconnect the

B+

lead from the start

solenoid.

Remove the control panel mounting screws and

lower the control panel.

Remove the two bottom mounting nutssecuring the

inlet baffle assembly. Lift the inlet baffle up and

move it to the right side.

,..a.

FAN

HUE

.

-1.

.

.-.

FIGURE

8-4.

SECURING FAN HUB

ASSEMBLY FOR REMOVAL

10.

Installa pulleron theendofthefan hubasshownin Figure

8-5.

Use two

1

/4

inch thread cutting cap-

screws

to

secure the puller

to

the fan hub. Place a

washer on the end

of

the rotor shaftto protect it from

the puller center

screws.

Tighten puller

center

screwagainst washer until fan hub pullsfreeof rotor shaft. Remove puller when complete.

ASSEMBLY

8. Remove the air filter cover, retainer, and filter (Figure 6-7). Remove the three boltssecuring the plastic fan

to

the fan hub assembly and remove the fan and

the scroll housing together (Figure

8-3).

9.

Attach a special

tool

to the fan hub to keep

it

from

rotating (Figure 8-4). Remove the rotor through-

bolt.

Be

careful not to lose thealignment key behind

the rotor through-bolt washer (Figure 8-3).

M-1727.1

FIGURE

8-5.

PULLING

THE

FAN

HUB ASSEMBLY

8-8

.

11.

Prepare the brushes for endbell removal. Discon-

stator laminations next to the alignment tabs(Figure

12.

13.

nect wire harness leads from brush block and pull

each

brush

outward from the holder

and

at

the

same

time insert a piece

of

wire into the small hole in the

endbell at bottom of brush block. See Figure

8-6.

Carefully guide the wire through the brush block and then release each brush. Verify that each brush is held off the slip rings by the wire.

The brushes will be damaged

(BCAUTIONI

during disassembly

if

not held

off

the slip rings. Make certain wire is in place

before removing the generator endbell.

BRUSH

BLOCK

M-l?ZE

FIGURE

8-6.

BRUSH

BLOCK

Remove the two starter mounting bolts that secure the starter

to

the endbell. Remove the choke assembly from the generator endbell and disconnect the leads attached to the resistor at the top of the endbell. Remove endbell mounting screws and remove the endbell. Secure springs for reinstallation.

Sharp edges can cause severe

(BWARNINGI

personal injury. Wear gloves

when handling components with sharp edges.

Careless handling of rotor or stator can damage the insulation

on the windings.

Do

not allow windings

to

be

brushed or scraped during removal.

Inspect stator housing for stator holding pins

(2)

used on some

early production unils produced before serial number

126644

(Figure

8-2).

Remove holding pins by gripping pin head with a locking pliers and pull outward with a slight counterclockwise twist. Stator holding pins are not required to reassemble the

generator and should be discarded.

Remove each

of

the wire connectors from the stator assembly. Wear gloves when handling the stator for protection from sharp edges. Insert two 6-inch

screw drivers into the holes

on

oppositesides of the

8-

8-3).

Squeeze screw driver handles togetherand

carefully

pull

stator straight

out

of

the

endbell.

If

stator will not slide out, tap on generator housing while pulling on stator to remove.

Do

not bend or

flex stator wire terminals or damage can occur.

Bending or flexing the stator terminals can cause breakage

of

the terminals. Use caution when removing the sta-

tor wires and when handling the stator.

14.

Place a wooden shim between the bottom

of

the stator housing and the base assembly to prevent movement between the generator and the base. Carefully tap on the rotor shaft with a lead hammer to free tapered rotor shaft from the crankshaft. Be careful to avoid striking the collector rings. Pull the rotor straight out and locate the Woodruff key used

to

align the rotor shaft with the crankshaft

The collector rings will

be

dam-

-

aged

If

struck during rotor re-

moval. Use caution to avoid hitting collector rings

when using lead hammer on rotor shaft.

Generator

Assembly

Use

the following procedures to assemble the

generator:

1.

Prepare the set for stator and rotor installation. The stator and rotor must be installed while the sei is standing vertically on the engine end for correct alignment of the rotor shaft to the crankshaft. Raise

the generator end

of

the set and allow it to rest on

the engine end. Place a wooden block under the

muffler

to

hold the set level. Support the set to pre-

vent it from falling during service.

AWARN~NG

The generator set

is

heavy and

I

can result in severe personal

Injury

it

dropped during service. Support the

generator set during service to prevent

it

from

falling.

2.

Check to see that Woodruff key is installed properly

on engine crankshaft.

3.

Check the generator housing for burrs in the aluminum

slots

that the stator slides into. Remove burrs

and clean housing if required.

4.

Position the stator

so

the output connector terminals face outward from generator housing and orient stator lamination alignment tabs with mounting grooves in housing, as shown in Figure

8-3.

Carefully lower stator into generator housing.

If

necessary the stator can be lightly tapped on the lamination mounting tabs until the stator seats into the housing.

Careless handling of the stator can

damage the insulation

on

the stator

windings.

Do

Not brush windings against the hous-

ing or strike windings during installation.

5.

Align slot in rotor shaft with Woodruff key on crankshaft and lower rotor onto crankshaft. Make sure that the rotor is seated.

Misalignment

of

the rotor shaft

and the crankshaft can cause

damage to the rotor and stator assembly.Use care

when installing the rotor shaft

to

align the crank-

shaft and rotor shaft with the Woodruff key in the

crankshaft.

6. Attach the stator wire harness connectors

to

the

stator. Be careful not

to

bend connector terminals or

damage may occur. Refer to Figures 8-1 and

8-2

for

wiring locations. Use wire ties

to

secure stator leads

away from rotor and fan hub

to

prevent rubbing.

7.

Prepare endbell for installation. Place springs on

studs and lubricate O-ring. Verify that brushes are

held in holder with piece of wire. See Figure 8-6. Install endbell onto rotor bearing and secure with

endbell mounting screws.

The brushes will be damaged

@@%@I

during assembly if not held

off

the slip rings. Make certain wire is in place before installing the generator endbell.

8. Remove the piece

of

wire holding the brushes

off

the slip rings. Connect the F- lead wire

to

the

out-

board brush terminal and the F+ lead wire to the inboard brush terminal.

9.

Install fan hub onto rotor shaft and align key slot on

fan hub with key slot in end

of

rotor shaft. Install alignment key. Insert washer on rotor through-bolt and install into rotor shaft. Verify alignment of rotor shaft and fan hub. Use special tool

to

secure fan hub

assembly (Figure

8-4)

and tighten the rotorthrough-

bolt

to

the specified torque.

Leaking fuel will create a fire hazard which can result in.

severe personal injury or death.

If

leaks are detected correct immediately. Replace worn fuel line components before leaks occur.

15.

Connect the

B+

lead to the start solenoid. Attach

K3

relay

to

the inlet baffle assembly (Figure

7-3).

16.

Install the control panel. Inspect assembly, check all electrical and mechanical connections for correct fit and location. Place enclosure cover on set and secure with side mounting screws.

17.

Install the generator set in the vehicle and securely

fasten all mounting screws and hardware. Connect the fuel line, exhaust system and electrical systems

in reverse order

of

disassembly. Refer

to

Set Remo-

val (section

5).

18.

Fill crankcase with oil of the recommended classifi-

cation and viscosity.

BRUSHES

AND

SLIP

RINGS

This section covers brush replacement and slip ring

service.

Brush

Replacement

Follow Generator Disassembly procedures (this section) through fan hub assembly removal. Inspect the brushes and brush block for burn marks or other damage.

If

the brushes appear

to

be in good condition, use a

piece

of

wire (modified as shown in Figure

8-7)

to check

for

excessive brush wear. Insert the painted end

of

the wire through the hole above each brush. Make sure the wire is resting on the brush and not on the spring.

If

the

painted part of the wire is not visible. The brush is excessively worn and must be replaced. Always replace

the brush springs when installing new brushes

to

maintain proper tension on the brushes. Clean carbon deposits from brushes and slip rings (see Slip Ring Service section). Use the following procedure

to

replace the

brushes:

10. Lower the generator end

of

the set and allow set to

rest on base.

11.

Attach choke assembly

to

endbell. Install two starter

mounting

bolts

through endbell and attach starter at

specified torque. Attach connectors

to

resistor on

endbell (Figure

8-1).

12.

Attach fan

to

fan hub with three bolts and install

scroll housing. Install air filter, retainer, and filter

cover.

13.

Install air inlet baffle assembly and tighten mounting

14.

Connect fuel line to fuel pump and inspect the fuel sure fuel supply line does not rub against anything

that

could cause breakage.

nuts

to

specified torque.

supply line for cuts cracks and abrasions. Make

M-1729

FIGURE

8-7.

BRUSH

WEAR

CHECK

8-1

0

1.

Remove the brush block mounting screws and

lift

2.

Remove

brushes

and

springs from holder and

out the brush block.

replace with new parts (see Figure 8-8).

SPRING

BRUSH

I

6-1179

FIGURE

8-8.

BRUSH

REPLACEMENT

3.

Pull each brush outward from brush holder and insert a stiff wire through the small hole in the base of the holder. See Figure

8-6.

The wire holds the

brushes

off

the slip rings during assembly.

Confact with rotating machinery

llEEE%l

can

result

in

severe

personal

injury.

Keep

hands,

cloihing,

jewelry

and

fingers

clear

while

servicing slip rings.

ACAUT~ON

Careless handling

of

rotor

can

D

damage the insulation on the

windings.

3.

Clean rotor and prepare for reinstallation. Follow Generator Assembly procedures (this section) to reinstall rotor and remaining generator components.

VOLTAGE REGULATOR

(VR1)

TEST

Confirm that voltage regulator VR1 is faulty before replacing it. Use a meter with adiodechecking function (Fluke Model

73,

or equivalent Multimeter) to perform

the following tests.

1. Disengage the wiring connector and remove the voltage regulator (Figure 8-9).

2.

With the meter on “Diode Check”, test between connector terminal pairs 5-9,7-9.10-9,11-9,12-9, 10-5,5-11 5-12 and

5-3.

(Figure8-9).

It

is important that the positive lead of the meter be connected to the first terminal of each pair.

3.

Replace the voltage regulator

if

any reading indi-

cates “short” or “open”. except for pair

10-5,

which

should indicate “open”.

,

Inspect slip rings before installing brush block.

See

Slip Ring

Service (this section).

4.

Install brush block in endbell but do not tighten mounting screws.

5.

Remove the wire holding the brushes

off

the slip

rings. Adjust the brush block

so

that the brushes are centered on the slip rings, then tighten mounting screws.

6.

Follow Generator Assembly procedures (this sec-

tion) to reinstall fan hub and remaining generator

components.

Slip

Ring

Service

Follow Generator Disassembly procedures (this sec-

tion) through fan hub assembly removal. Inspect the slip

rings for grooves, pits, or other damage. A Scotch Brite pad can be used

to

remove light wear and for surface

finishing.

If

the slip rings are in bad condition and there is no power build-up, refinish using a fine sandpaper. Use the following procedure

to

service:

“Short” is indicated by zero or a number very nearly zero. Meters

of

diflerent make indicate “open” differently. Read the

meter instructions.

If

in doubt, compare with readings

of

a regu-

lator

of

the same part number known to

be

good.

4.

If the regulator checks “good”, there is a small

chance that it may be”bad”. Recheck it on agenset.

Also

check that the connector pins are secure in

both connector ends.

GENERATOR TESTING

This section covers test procedures for the generator

rotor and stator windings. Follow the troubleshooting procedures in this section

to

locate the required correc-

tive action.

Perform the Field Voltage Test to confirm that field voltage is available to the rotor brushes through the voltage regulator for field flashing and voltage buildup.

Check all wire harness connectors and leads

for

continuity

prior

to

testing

or

generator disassembly. Refer to Figurer

8-2

and

8-3

wire

locations.

1.

2.

Field

Voltage Test

being supplied to the brushes from the voltage regulator

for voltaae builduD.

Follow Generator Disassembly (this section) to

A voltage check can be made to determine

if

voltage is

remove generator endbell and rotor. Place rotor in machine lathe and center. Turn rotor

I

Connect a DC voltmeter positive

(+)

test lead into the

voltage regulator plug

(Pl)

at pin 9 and connect the negative (-)test lead into the voltage regulator plug at pin

10.

The voltage regulator plug remains connected to

and use fine sandpaper against rotating slip rings to clean and true slip rings. Turn rotor until all grooves or roughness are smoothed out.

8-1

1

the voltage regulator and test prods should be secured

so

that they are not being held during testing. See Figure

8-9.

Start the generator set and allow it to stabilize. Measure the field voltage with no load applied and then with full load applied. Both readings should fall within a range of

18

to

60

volts DC.

If

the set cranks but will not run, check to see that battery voltage is being supplied to the voltage regulator pin

7

(positive lead) and ground (negative

lead) during

start

up.

If

battery voltage (approximately

12

volts) is being supplied to the voltage regulator at pin

7,

and no output voltage was measured, replace the voltage regulator and retest.

If

battery voltage

is

not supplied to the voltage regulator during starting, refer to Control section

(7)

for troubleshooting procedures.

Contact with rotating machinery can

result in severepersonalinjury. Keep hands, clothing,jewelry and fingers clear while servicing slip rings.

Electrical

shock

can cause severe

'AWARNINGI

persona/ injury

or

death. Use

extreme caution when working

on

electrical circuitry-

Attach and remove meter leads only when generator

set

is

not operating.

Do

not touch meter

or

meter leads

.

-.

--

---

--

---

---_

---

during testing.

.0---

.HR

6%

.t

I

\

ACCESS

COVER

VOLTAGE

REGULATOR

7

CONNECTOR PLUG

ES-1763

FIGURE

8-9.

VOLTAGE REGULATOR CONNECTOR PLUG

(Pl)

8-1

2

.

Rotor Test

The rotor

can

be tested for grounded, open, or shorted

windings using

an

ohmmeter. Figures 8-10

and

8-11

show the rotor removed from the generator set for test-

ing. The rotor can be tested without removing it from the generator. To gain access to the slip rings, follow the Generator Disassembly procedures (this section)

through the fan hubassembly removal procedure. Usea stiff wire to hold the brushes

off

the slip rings during testing. Refer to the Brushes and Slip Ring section for the procedures to use for inserting the wire.

If

available, it

is

recommended that a megger or insulation resistance

meter be used

for

ground tests.

Ground

Test:

To

test for grounds, set the ohmmeter for the highest

resistance scale. Touch one test prod to the rotor shaft

and hold

it

there. Touch the other test prod to one of the slip ringsasshown in Figure8-10.Areading of lessthan one megohm indicates the rotor isgrounded. Replacea grounded rotor with a new rotor.

ES1764

FIGURE

8-10.

GROUNDED ROTOR TEST

Open

or

Shorted

Test:To test for open windings, set the

ohmmeter on the highest resistance scale. Place test

prods

on

the

slip

rings

as

shown

in

Figure

8-1

1. The

ohmmeter should indicate continuity between the slip

rings.

A

high resistance reading indicates a poor connection or an open winding. Check the connection between the slip rings and rotor lead wires. Replace rotor

if

rotor winding is open.

To test for shorted winding, set the ohmmeter on the

lowest scale. Place the test prods on the slip rings as

shown in

Figure8-11.Areadingoflessthan16ohmsat

77°F

(25OC)

indicatesshorted windings. Replace rotor

if

winding

is

shorted.

If

rotor tests good proceed to stator

tests.

ES-1755

FIGURE

8-11.

OPEN

OR

SHORTED ROTOR TEST

.

8-1

3

Stator

Test

The stator can betested for grounded or open windings using an ohmmeter. Testing for shorted windings requires a digital type ohmmeter that can read to within

0.01 ohms. Figure 8-1

2

shows thestator removed from thegenera-

tor

for testing. The stator can be tested without removing

it from the generator.

If

generator is assembled, gain

access

to

the stator by following the Generator Disassembly procedures (this section) through the fan hub assembly removal procedure.

To perform stator tests, carefully remove all four con-

nector plugs from the stator.

Do

not bend or flex stator

wire

iermi-

ISEEEI

na/s

or

breakage can

occur.

If

available, it

is

recommended that a rnegger

or

insulation resistance

meter

be

used for ground tests.

Ground Test:

Set the ohmmeter for the highest resistance scale and then connect one test prod to the generator housing or stack

if

removed. Touch the other test

prod (see Figure 8-12)

to

the terminals specified in

Table 8-1. A reading

of

less than one megohm indicates

a ground. Replace a grounded stator with a new stator.

B1'

x3

\

X6

x4

a2

ES-1766

FIGURE

8-12.

STATOR ASSEMBLY

TABLE

8-1

STATOR GROUND TEST

OHMMETER

TEST LEAD LOCATION READING

T1

toGround Infinity

T2 to Ground Infinity

B1 to Ground Infinity

Infinity

B2

to Ground Q1 toGround Infinity Q2 to Ground Infinity

Open

or

Shorted Stator Windings Test:To

test for open windings, set the ohmmeter for the highest resistance scale and then connect the test prods (see Figure 8-12) to the terminals specified in Table 8-2. The ohmmeter should indicate continuity between terminals.

A

high

resistance reading indicates an open winding.

If

an

open circuit is measured replace the stator. To test for shorted windings, use a digital type ohmmeter

that reads to within 0.01 ohms. Connect the test prods to

the terminals specified in Table 8-2. A reading of less than the value shown in Table 8-2 at 77OF (25OC) indi-

cates a shorted winding.

If

stator tests indicatea shorted

winding, replace the stator.

If

stator tests good, check jumper leads

XI

-X2, X3-X4, and X5-X6 for continuity, and for good electrical connection with the stator terminals. Also check remaining stator wire connections for continuity and good electrical contact with stator. See Figures 8-1 and 8-2for wire locations.

TABLE

8-2

STATOR OPEN AND SHORTED

WINDING TEST

'EST LEAD LOCATION

T1 -X1 T2-X2 B1 -X3 B2-X4 Q1 -X5 Q2-X6

T1

-X1

T2-X2

B1 -X3 B2-X4 Q1 -X5 Q2-X6

OHMMETER READING

ACCEPTABLE RESISTANCE RANGE)

AT

77OF

[25'C])

60

HERTZ STATOR

0.191

to

0.233

0.191

to

0.233

0.024

to

0.030

0.024

to

0.030

0.61

5

to

0.751

0.615

to

0.751

50

HERTZ STATOR

1.01

3

to

1.238

1.01 3

to

1.238

0.090

to

0.1 10

0.090

to

0.1 10

0.738

to

0.902

0.738

to

0.902

.

8-1

4

ROTOR BEARING REPLACEMENT

The rotor bearing is pressed onto the rotor shaft. This bearing must

be

replaced very carefully

to

avoid damag-

ing the collector ring assembly and the rotor shaft. Use

the following procedures to replace the rotor bearing.

1.

2h.

28.

Measure and record the distance between the bearing and the collector ring assembly, (referenced later for reassembling). See Figure

8-1

3.

The bearing casing

is

made

of

k!@@&%l

hardened steel. When struck,

it

will shatter into smallpieces and can cause severe personal injury. Use protective eye wear and cloihing when replacing the rotor bearing.

ACAUT~ON

Heating the rotor bearing

for

D

removal or installation can

cause damage to the bearing and the collector ring housing.

Do

not heat the rotor bearing.

If

available, use a small puller with grips that will fit between the bearing and the collector ring assembly. Cover the end of the rotor shaft with a steel plate to prevent deformation of the shaft during removal.

If

a suitable puller is not available, wrap the collector

ring with a cloth for protection and cut off the outer race of the bearing using a small hand grinder with a

cutting wheel. Be careful to avoid cutting the collector ring assembly. Remove the bearings and make two cuts approximately halfway through the inner

race

180"

apart. See Figure

8-1

4.

Place rotor with one cut face down on a hard surface and center a cold chisel on the other cut and strike to split apart. Be careful not to damage the rotor shaft. The bearing casing is made of hardened steel that can shat-

ter into small pieces. Use protective eye wear and

clothing to protect yourself from injury when striking

the bearing casing.

Inspect the rotor shall for dirl

or

corrosion.

If

necessary, clean

with

emery

cloth before before installing new bearing.

MEASURE

SPACE BETWEEN

BEARING

AND

COLLECTOR RING

-

ASSEMBLY

11

3.

Place the rotor shaft, engine end down, onto a

1-

1/16

inch

(27

mm)

O.D.

steel shaft or use a plug

mated

to

the engine end of the rotor shaft to protect

the shaft taper from damage when pressing bearing

into place.

4.

Refer to measurement taken in step

1.

Press bearing

onto rotor shaft (press on inner race only) until

it

rests at the same distance from the collector ring

assembly as the original bearing.

Do

not place bear-

ing closer than

0.14

inches

(3.5

mm)

to the collector

ring or arcing can result. Check bearing seal for

damage after installation.

6-1215

FIGURE

8-14.

ROTOR

BEARING REMOVAL

ROTOR

BEARING

COLLECTOR RING ASSEMBLY

6-1216

FIGURE

8-13.

ROTOR

BEARING SPACING

8-1

5

Section

9.

Engine

-

Block

Assembly

INTRODUCTION

This section covers service procedures for the engine block assembly. This assembly includes the cylinder block, cylinder head, valve system, piston and connecting rod, crankshaft, camshaft, and oil pan. Performing any major service will require generator set removal from the vehicle (see Set Removal, section

5).

To

gain

access

to

the engine block assembly, the generator and primary engine systems must be removed. Refer to the previous sections for the disassembly procedures.

d

A

suggested order of disassembly for the engine block

assembly follows:

1.

oil pan and oil level switch

2.

head cover, breather and cowling

3.

rocker arms and push rods

4.

cylinder head, valve springs and valves

5.

crankcase cover and camshaft,

6.

connecting rod and piston

7.

crankshaft and governor lever shaft

OIL

PAN AND

OIL

LEVEL

SWITCH

Remove the oil plug and drain the crankcase oil (if not previously drained).

Remove the oil pan mounting bolts and remove pan (see Figure

9-1).

Remove oil level switch mounting bolts and remove

switch. Clean oil pan and use new gasket when reinstalling.

Torque all mounting bolts to the specified mounting torque (see Torque Specifications section).

'OIL

PLUG

FIGURE

9-1.

OIL

PAN

REMOVAL

9-1

HEAD COVER

Remove the head cover

to

gain access

to

the cylinder

head and valve system. Use the following procedure

to

service.

1.

Use a

10

mm socket wrench to remove head cover

mounting bolts and pull

off

head cover. See Figure

2.

Clean head cover. Be careful not to damage outer sealing edge where gasket fits.

3. Clean cylinder head cover and cylinder head thoroughly where gasket rests. Use new gasket when reinstalling and make sure breather assembly is correctly installed in cylinder head cavity.

4. Place head cover in position and torque until all bolts are tightened

to

the specified torque.

9-2.

BREATHER

ASSEMBLY

FIGURE

9-2.

HEAD COVER REMOVAL

CYLINDER HEAD

Remove the cylinder head for cleaning when poor engine performance is noticed or

to

inspect the valves.

Use the following procedures

to

service.

1.

Lift

breather out of cavity in cylinder head.

2.

Remove lock nut and adjusting bolts from rocker

arms, then remove rocker arms and push rods.

3. Removecowling mounting bolts and lift

off

cowling.

4. Use a

12

mm socket wrench to remove the cylinder

head mounting bolts and lift

off

the head.

5.

Clean out all carbon deposits. Be careful not

to damage outer sealing edge where gasket fits. The head

is

made of aluminum and can be damaged by

careless handling.

6.

Use new head gasket and clean both cylinder head and cylinder block thoroughly where gasket rests.

7.

Place head in position and follow head torque tightening sequence shown in Figure 9-3. Start out tightening all bolts to

11

ft-lb

(15

Nom), then tighten

to

the specified torque (see Torque Specification

section).

Vl-1036

FIGURE

9-3.

CYLINDER HEAD TIGHTENING

SEQUENCE

VALVE

SYSTEM

The engine in the

KV

generator set uses an overhead

valve design as shown in Figure 9-4.

A

properly functioning valve system is essential for good engine performance. Access

to

the valve system can be gained

by

removing the head cover and the cylinder head. Use the following procedures

to

inspect and service the valve

system.

.

Warping can occur

if

the head

is

-1

removed while

hot.

Waif

until

the

engine has cooled before removing cylinder head.

9-2

Inspection

Valve Face:

Check the valve face for evidence of burn-

ing, warping, out-of-round, and carbon

deposits

(see

Figure

9-6).

Burning and pitting are caused by the valve failing to

seat tightly. This condition is often caused by hard car-

bon particles on the seat.

It

may also be due

to

weak

valve springs, insufficient tappet clearance, warping,

Warping occurs mainly due to exposure to intense heat. Out-of-round wear follows when the seat is pounded by a valve whose head is not in line with the stem and

guide.

If

a valve face is burned or warped, or the stem

worn, install a new one.

Too

much clearance in the intake guide admits air and oil into the combustion chamber, affecting carburetion, increasing oil consumption, and making heavy carbon deposits. Clean metal is a good heat conductor but carbon insulates and retains the heat. This increases combustion chamber temperature which causes warping and burning.

.

and misalignment.

VALVE

SPRINGS

VT-1037

FIGURE

9-4.

OVERHEAD VALVE

SYSTEM

Unburned carbon residue gums valve stems and causes them

to

stick in the guide. Deposits of hard carbon with sharp points projecting become white hot and cause pre-ignition and pinging.

Valve Removal

The valves can be removed from the cylinder head

without the use

of

special tools. Depress the valve spring retainerusing a9/16inch crowsfootona6inch extension and remove keeper. See Figure 9-5. Remove spring retainer and spring, then remove valve.

FIGURE

9-5.

VALVE REMOVAL

VALVE FACE

VALVE

GUIDE

VALVE STEM

VT-1038

VT-1020-1

FIGURE

9-6.

VALVE FACE, VALVE STEM AND VALVE GUIDE

INSPECTION

9-3

Stems

and

Guides:Always check stems and guides for

wear as shown in Figure

9-6.

Use a hole gauge to measure the valve guide. When clearance with stem exceeds original clearance by

0.002

inch

(0.05

mm), replace the valve or cylinder head, which includes the valve guide, or both.

Springs:

Check valve springs for cracks, worn ends, and distortion. If spring ends are worn, check valve retainer for wear. Check for spring distortion by placing spring on aflat surface nextto a square. Measure height of spring and rotate it against a square to measure

distortion, see Figure

9-7.

Replace any valve spring that

is weak, cracked, worn, or distorted.

\'

VI-1039

FIGURE 9-7. VALVE SPRING CHECKS

Reconditioning

Valves

and

Valve Seats

Valves should not be hand lapped because the sharp contact made between thevalve face and valveseat will be destoryed. Valve faces must be finished in a machine at

44.5

to

45

degrees. Each valve must have a minimum

of 1/16inch

(1.6mm)margin,Figure9-8.Ifthevalvehas

less margin than this

it

will heat up during the compres-

sion stroke and pre-ignite the mixture, causing

loss

of

power and economy. This valve

is

also susceptible to

warping and breakage.

Not

all valves can be reconditioned. A badly warped valve must be replaced because the excessive grinding required to make

it

seat correctly removes the margin.

To

make a valve gas-tight, every trace of pitting must be

removed from the valve face and seat. Deeply pitted

or

cut valves must be replaced.

6

INCH

(1.6

rnm)

MINIMUM

REFER TO SPECIFICATIONS FOR

CORRECT DIAMETER

II

44.50 - 450

vT.1040

CHECK

FOR

BENT STEM

Valve seats should be ground with a

45'

degree stone to the specified width. Grind only enough to provide proper seating. See Figure

9-9.

Place each valve in its proper location. Check each

valve for a tight seat. Make several marks at regular

intervals across the valve face using machinists bluing.

Observe if the marks rub

off

uniformly when the valve is dropped against the seat. The valve seat should contact the valve face evenly at all points. The line of contact should be at the center of the valve face.

VI-1041

FIGURE

9-9.

VALVE SEAT

Intake Valve Seal Replacement

A

worn or cracked valve seal can cause high oil con-

sumption and spark plug fouling. Replace a defective

intake valve seal as follows:

1.

Pull the old valve seal out carefully to avoid damag-

2.

Coat the intake valve stem with engine oil and insert

3.

Press valve seal into valve guide by hand.

4.

After insertion, usea special tool made for installing the seal (Figure

9-1

0)

to press the seal into the valve guide until the shoulder of the seal restsagainst the cylinder head.

ing the valve guide.

it

into the valve guide.

VALVE

SEAL

INSTALLATION TOOL

\

VALVE SEAL

e'lL"E-GulDE

VT-1043

\

FIGURE

9-8.

VALVE MARGIN

FIGURE

9-10.

VALVE SEAL INSTALLATION

9-

4

Valve Seat and Valve Guide Replacement

Worn valve stem guides

or

valve seats that are loose,

cracked,

or

severely

pitted

should

be

replaced

by

replacing the cylinder head assembly. Both the valve stem guides and the valve seats are available only as part

of

the cylinder head assembly.

Valve

Lash

Adjustment

The engine is equipped with adjustable valve tappets. Adjust the valve clearance when the engine is at ambient temperature. Proceed as follows:

1.

2.

3.

4.

5.

6.

7.

Follow

head cover removal instructions (this section). Inspect valve stems for proper alignment with tappets.

Advance the engine until both

of

the valves are closed and there is no pressure on the valve lifters (piston at top dead center).

Clearances are shown in the Specifications section. For each valve, the gauge should just pass between

the top of the valve stem and the rocker arm. (see

Figure

9-1

1).

Check the cylinder head mounting bolt torque (see Cylinder Head, this section) before performing valve lash adjustment.

To correct the valve clearance, place a

14

mm

wrench on the adjusting nut and a

10

mm wrench on the outer locking nut. Loosen the outer locking nut and turn the adjusting nut as needed

to

obtain the

correct clearance. Tighten locking nut after adjust-

ment is made. Recheck the valve clearance after adjustment has

been made and also check the rocker arm bolts

to

see that they have not loosened asa result

of

adjust-

ing the valve lash. Reinstall the head cover and torque head cover

bolts

to

specified torque.

CRANKCASE COVER

Remove the crankcase cover mounting

bolts

and lightly

tap

cover

with plastic

faced

hammer

to

loosen.

Be

care-

ful not

to

lose crankshaft and camshaft shims. When installing the cover make sure the governor shaft is properly positioned.

Use

a new gasket and clean the crankcase cover and the engine block where the gasket rests. Place crankcase cover in position and torque until all bolts are tightened to the specified torque (see Torque Specifications section).

C-1113

FIGURE 9-12. CRANKCASE COVER

CAMSHAFT AND TAPPET REMOVAL

The camshaft gear is pressed onto the camshaft and

should be removed from the engine as a set. Check for matching mark with crankshaft before removing camshaft. The tappets can be removed after camshaft removal. See Figure

9-1

3.

TAPPETS

CAMSHAFT

GEAR

C-1114

FIGURE 9-11. VALVE

LASH

ADJUSTMENT

FIGURE 9-13. CAMSHAFT

AND

TAPPETS

9-5

GOVERNOR

With the crankcase cover removed, the governor can be

inspected or disassembled for service. The governor assembly must spin freely on the center pin without excessive looseness or wobble. Sleeve tip wear is the

most

common cause of governor failure.

If

governor sleeve, gear, or flyweights are worn or otherwise damaged replace them. To disassemble, remove the snap

ring from the governor center pin and slide governor

gear assembly

off

mounting shaft being careful not

to

lose outer washer. See Figure9-14. To install governor, assemble in reverse order of removal (see inset drawing, Figure 9-14, for position of flyweight and sleeve).

v

CT-1090

To remove the governor shaft, remove the retainer clip outside the block, then lower the governor shaft into the

crankcase.

FIGURE

9-15.

REMOVING

WEAR

RIDGE

1. Remove two bolts from connecting rod. Mark direction of assembly for connecting rod, cap, and splasher.

2.

Lift the rod cap from the rod and push the piston assembly out of the top

of

the cylinder with the

handle of a hammer. Be careful not

to

scratch the

crankpin or the cylinder wall when removing.

The piston

is

fitted with two compression rings and one oil control ring. Remove these rings from the piston using a piston ring expander as shown in Figure 9-16.

\

\\

CT-1089

FIGURE

9-14.

GOVERNOR

PISTON ASSEMBLY REMOVAL

AND SERVICE

The piston assembly consists of the piston, piston pin,

and connecting rod assembly. After piston removal, all parts must be carefully inspected for damage and wear before replacing. Remove the carbon from the top of the cylinder bore and check for a ridge. Remove ridge with a ridge reamer (see Figure 9-1

5)

before attempting piston

removal. Remove the piston as follows:

-1

Improper use

of

a

ridge reamer can

damage

fhe

cylinder bore. Follow

fool

manufacfurer's instructions and be careful when

using a ridge reamer.

CT-1059-1

FIGURE

9-16.

REMOVING PISTON

RINGS

9-6

Remove the piston pin retainer from each side and push

the piston pin out. Remove dirt and deposits

from

the

piston

surfaces

with

an

approved

cleaning solvent.

Clean the piston ring grooves with

a

groove cleaner

(Figure

9-17)

or the end

of

a piston ring filed to a sharp

point. Care must be taken not to remove metal from the

groove sides.

Using caustic cleaning solvent or

damage piston.Use only parts cleaning solvent. When cleaning the connecting rod in solvent, include the rod

bore. Blow

out

all passages with low pressure

com-

pressed air.

8

-1

wire brush for cleaning

pistons

will

Most

parts cleaning solvents are

flammable and can result in severe

personal injury

if

used improperly. Follow the manu-

facturer's recommendations when cleaning parts.

CT-1061

FIGURE

9-18.

CHECKING RING LAND

CT-1060

FIGURE

9-17.

CLEANING RING GROOVES

c

Inspection

The following covers inspection procedures

for

piston

.

and connecting rod.

Piston

InspectionAnspect

the piston

for

fractures at the ring lands, skirt, and pin bosses. Check for wear at the ring lands using a new ring and feeler gauge as shown in Figure

9-18.

Replace the piston when the side clear-

ance

of

the top compression ring reaches

0.0039

inch

(0.1

mm).

Improper width rings or excessive ring side clearance can result in ring breakage. New rings in worn ring grooves do not have good cylinder wall contact (Figure

9-19).

RING CONTAC

CYLINDER

WALL

CT-1062

FIGURE

9-19.

NEW RING

IN

WORN RING GROOVE

Replace piston showing signs of scuffing, scoring, worn ring lands, fractures

or

damage from pre-ignition.

Connecting Rod Inspection:

Replace connecting rod bolts and nuts with damaged threads. Replace connecting rod with deep nicks, signs of fractures, scored bores or bores out

of

round more than

0.002

inch

(0.05

mm).

9-7

Use a new piston pin to check connecting rod for wear.

A

push fit clearance is required and varies from engine

to engine.

If

a new piston pin falls through a dry rod pin bore as a result of its own weight, replace the rod or bushing as required.

Piston

Inspection:

Replace piston pin that is

cracked, scored, or out of round more than 0.002 inch

(0.05

mm).

Piston Clearance

Proper piston tolerances must be maintained for satis-

factory operation. Use a micrometer to measure the piston diameter at the pointshown in Figure9-20. When the cylinder bore is measured (see Cylinder

Blocksec-

lion),

subtract the piston diameter from the cylinder bore

diameter to obtain the piston pin

to

cylinder wall clearance. Refer to the Dimensions and Clearances section for the recommended piston clearance.

CT-1063

FIGURE

9-20.

PISTON

CLEARANCE

MEASUREMENT

Fitting Piston Rings

Before installing new rings on the piston, check the ring gap by placing each ring squarely in the cylinder, at a position corresponding to the bottom of its travel (Figure 9-21). The gap between the ends of the ring is given in

Dimensions and Clearances section.

The practice of filing ring ends to increase the end gap is

not recommended.

If

the ring end gap does not meet specifications, check for the correctness of ring and bore sizes.

Rings of the tapered type are usually marked

TOP

on

one side, or identified in some other manner. Install

these rings with the identification mark toward the

closed end

of

the piston.

FIGURE

9-21.

CHECKING RING

GAP

Piston Assembly Installation

Lubricate all parts with clean engine oil. Position the piston on the connecting rod. Install the piston pin. The piston pin isafull-floating type and must be kept in place (in the piston) with two lock rings, one at each side.

Install the lock rings and see that they are properly

in

place before installing the piston and connecting rod in the engine.

Install the rings on the piston beginning with the

oil

control ring. Use a piston ring spreader to prevent twist-

ing or excessive expansion

of

the ring. Compression rings are marked with a dot or the word "top" on one side

of

the ring to indicate which side faces the top

of

the piston. Unmarked piston rings can be installed either way.

Stagger ring gaps 120 degrees apart. Do not position ring gaps on thrust face of cylinder.

CONNECTING

-/

ROD

MARK

CT-1091

FIGURE

9-22.

ROD

CAP

ASSEMBLY

9-8

Installing Piston

in

Cylinder:

When installing the pis-

ton assembly, observe markings on the connecting rod,

cap,

and

splasher

and

assemble

in

correct position.

See

Figure

9-22.

3.

Tap piston down into bore with handle end of hammer until connecting rod is seated on crankpin.

Check

crankpin

clearance

before

proceeding

to

#4

step (see Crankpin Clearance section).

1.

2.

+

Turn Crankshaft

to

position crankpin at bottom

of

its

stroke. Lubricate piston assembly and inside

of

cylinder.

Compress rings with

a

ring compressor

as

shown

in

Figure

9-23.

4.

Lubricate the rod crankpin and install the connecting rod cap. Tighten connecting rod bolts to specified torque.

The bearing cap must be tapped several times

to

properly align it with the connecting rod. Clearance

varies on the crankpin

if

this

is

not done. Crank the

engine by hand

to

see that the crankshaft turns

freely without binding.

Crankpin Clearance

1.

Mark parts

so

they can be installed in their original

positions, and wipe all parts clean of any oil or

grease.

2.

Place a piece of the correct size Plasti-gageacross the full width

of

the rod cap about

1

/4

inch

(6

rnrn)

off

center.

3.

Install the rod cap and tighten to the specified

torque.

Do

not rotate the crankshaft after the cap is

in place.

4.

Remove the rod cap and leave the flattened Plastigage on the part to which it adheres. Compare the widest point of the flattened Plasti-gage with the graduations on the envelope (see Figure

9-24)

to

determine the crankpin clearance.

FIGURE

9-23.

INSTALLING PISTON

FIGURE

9-24.

MEASURING CRANKPIN CLEARANCE

9-9

CT-1092

CRANKSHAFT

Remove the crankshaft after the connecting rod and piston have been removed, carefully pull the crankshaft out of the oil seal and bearing.

Inspection

Check the crankpin

O.D.

and finish.

If

it is worn or scored

and cannot be smoothed out by polishing or

if

it exceeds

the allowable size limit, the crankshaft should be

replaced.

Installation

Lubricate the bearings with engine oil. Slide the crankshaft into the bearing. Install the crankcase cover and check

to

see that the crankshaft turns freely.

Checking Endplay

With the crankcase cover installed, check the crankshaft endplay at the point shown in Figure

9-25.

Refer

to

the Dimensions and Clearances section for the recommended crankshaft endplay.

If

necessary add or remove shims as required and recheck endplay. Verify that the crankshaft turns freely without binding.

FIGURE

9-25.

CHECKING ENDPLAY

CYLINDER

BLOCK

Cleaning

After removing the piston, crankshaft, cylinder head, etc., inspect the block for cracks and extreme wear.

If

block is still serviceable, prepare

it

for

cleaning as

follows:

1.

Scrape all old gasket material from block.

2.

3.

Remove grease and scale from cylinder block by agitating in a bath of commercial cleaning solution

or

hot soapy washing solution.

Rinse block in clean hot water to remove cleaning solution.

Inspection

c

When rebuilding the engine, thoroughly inspect block for any condition that would make it unfit for further use. This inspection must be made after all parts have been

removed and block has been thoroughly cleaned and dried.

Make a thorough check for cracks using anystand-

ard method of crack detection. One method

of

crack

detection follows: Minute cracks may be detected

by coating the suspected area with a mixture of

25

percent kerosene and

75

percent light motor oil. Wipe the part dry and immediately apply a coating of zinc oxide (white lead) dissolved in wood alcohol.

If

cracks are present, the white coating will become discolored at the defective area. Always replace a cracked cylinder block. Clean the block and proceed.

Inspect all machined surfaces and threaded holes. Carefully remove any nicks or burrs from machined surfaces. Clean out tapped holes and clean up any damaged threads.

Check cylinder head mounting area for flatness with a straight edge and a feeler gauge.

Cylinder Bore Inspection:

Inspect cylinder bore

for

scuffing, scratches, wear, and scoring. If cylinder bore is scuffed, scratched, scored,

or

worn, the block must be

replaced.

When the appearance of the cylinder bore is good and there are

no

scuff marks, check cylinder bore for wear or

out-of-round

as

follows:

1.

Check cylinder bore for taper, out-of-round, and wear with a dial bore gauge, telescope gauge, or

inside micrometer. These measurements should be taken at four places, top and bottom of piston ring travel and parallel and perpendicular to axis of

crankshaft.

2.

Record measurements taken at top and bottom

of

piston travel as follows (see Figure

9-26).

A.

Measure and record as

“A”

the cylinder bore

diameter (parallel

to

crankshaft) near the top

of

cylinder bore where greatest amount of wear occurs.

B.

Also measure and record as

“B’

cylinder bore

diameter (parallel to crankshaft) at the bottom

of

piston travel.

9-1

0

4

C. Measure and record as ”C” cylinder bore

diameter (perpendicular

to

crankshaft) near the

top

of

cylinder

bore

where

greatest amount

of

wear occurs.

D.

Also measure and record as

“D”

cylinder bore diameter (perpendicular to crankshaft) at the bottom

of

piston travel.

E.

Reading

“A”

subtracted from reading

“B’

and

reading

“C”

subtracted from reading

“D”

indi-

cates cylinder taper.

F.

Reading

“A”

compared to reading

“C”

and read-

ing

“B”

compared

to

reading

“D”

indicates

whether or not cylinder is out-of-round.

If

out-of-round exceeds

0.0039

inch

(0.1

0

mm)

the cylinder block must be replaced.

Deglazing Cylinder Bores

Deglaze the cylinder bores,

if

there are no scuff

marks

and

no

wear or

out

of

round

beyond

specifications, before installing new rings. Deglazing gives afinefinish but does not enlarge cylinder diameter,

so

the original

pistons with new rings may still be used.

The reason for deglazing a cylinder is to provide cavities to hold oil during piston ring break-in.

1.

Wipe cylinder bores with a clean cloth which has been dipped in clean, light engine oil.

2.

Use a brush type deglazing tool with coated bristle

tips to produce a crosshatch pattern in the cylinder

bore.

3.

The deglazing tool should be driven by a slow speed drill. Move deglazing tool up and down in

cylinder rapidly enough to obtain a a crosshatch pattern as shown in Figure

9-27.

AVOID

THIS

FINISH

PRODUCE CROSS HATCH SCRATCHES

FOR

FAST RING SEATING

c-1091

TOP

END

OF

CYLINDER

FIGURE

9-27.

CROSSHATCHING

Never use gasoline or commer-

1-1

cial cleaners to clean cylinder

bores after deglazing

or

honing. These solvents

will not remove abrasives from the walls. Abrasives not removed from engine will rapidly wear rings, cylinder walls, and bearing surfaces of all lubricated parts.

-

AREA

*

--

j..

-.

BOTTOM

OF

RING

TRAVEL

CT-1090-1

FIGURE

9-26.

METHODS

OF

MEASURING

THE

DIAMETER

OF

A

CYLINDER

BORE

4.

Clean cylinder bore thoroughly with soap, water, and clean rags. Continue cleaning until a clean white rag shows no discoloring when wiped through cylinder bore.

9-1

1

TIMING GEARS

If

replacement of either the crankshaft gear or the cam-

shaft gear becomes necessary,

it

is recommended that

both gears be replaced. Each

of

these gears are

pressed on. The crankshaft gear requires agear separator and puller to remove and the camshaft gear requires a press

to

remove. Both gears can be installed using a

press. These gears use a Woodruff key

to

provide cor-

rect positioning on the shaft.

Each timing gear is stamped with an

“0”

near the edge.

The gear teeth must mesh

so

that these marks exactly coincide when the gears are installed in theengine-See Figure

9-28.

rc\

..

VI-1042

FIGURE

9-28.

TIMING GEAR ALIGNMENT

BEARINGS

One bearing is pressed into the engine block and the other bearing

is

pressed into the crankcase cover. The bearing in the engine block can be pressed out after the oil seal is removed (following section). The bearing in the crankcase cover can be pulled out using a puller. Clean the bearing mounting surfaces and press new bearings back in.

OIL

SEAL

Use an oil seal remover to pry the oil seal out of the engine block. Clean the oil seal resting surface and lubricate surface before installing new oil seal. Press new oil seal into the engine block until

oil

seal

is flush

with cylinder block boss (see Figure

9-29).

Lubricate the

lips

of

the oil seal with a light coating of grease. This provides initial lubrication until engine oil reaches the seal.

c

\

OIL

SEAL

‘3-1093

FIGURE

9-29.

OIL

SEAL

9-1

2

Section

10.

Service

Checklist

IAWARNING

I

EXHAUST

GAS

IS

DEADLY!

Exhaust gases contain carbon monoxide, an odorless and colorless gas. Carbon monoxide is poisonous and can cause unconsciousness and death. Symptoms

of

carbon monoxide poisoning can include:

Dizziness Nausea Muscular Twitching Headache Vomiting

Weakness and Sleepiness

Throbbing in Temples

Inability to Think Coherently

IF

YOU

OR

ANYONE ELSE EXPERIENCE ANY OF

THESE

SYMPTOMS, GET OUT

INTO THE

FRESH

AIR IMMEDIATELY.

If

symptoms persist, seek medical atten-

tion. Shut down the unit and

do

not operate until it has been inspected and

repaired. Never sleep in vehicle with the generator set running unless the vehicle interior is

equipped with an operating carbon monoxide detector. Protection against carbon monoxide inhalation also includes proper exhaust system installation and visual and audible inspection of the complete exhaust system at the start of each generator set operation.

1-RV

GENERAL INITIAL START ADJUSTMENTS

After servicing, inspect and test the complete installation

to

confirm that the generator set will operate prop-

erly and will pull full rated load. Check each

of

the

following areas before putting the set into service.

Adjust the carburetor idle adjustment screw and main adjustment screw as specified in the Fuel System section

to

allow starting.

Start the set and immediately adjust the governor speed adjustment screw

to

obtain a safe no-load operating speed. With no load applied, listen for any unusual sounds or vibrations. When the choke is completely open, adjust the carburetor and governor as specified in the Fuel System section.

MOUNTING

Examine all mounting

bolts

and supporting mmbers

to

verify that the generator Set is Properly r".Jnted. All fasteners should be tightened securely to prevent them from working loose when subjected

to

vibration.

OUTPUT CHECK

ApplyafuII load

to

makesurethesetwill produceitsfull

LUBRICATION

If

theengineoil wasdrained,fill thecrankcase with oil

of

the recommended C~aSSifiCatiOn and

ViSCOSitY.

Refer

to

the appropriate Operator's manual for

the

specific

rated output. Use a load test panel

to

apply a progres-

sively greater load until

full

load is reached.

recommendations and procedures.

EXHAUST SYSTEM

With the generator set operating, inspect the entire exhaust system including the muffler and exhaust pipe. Visually and audibly check for leaks at all connections, welds, gaskets, and joints and also make sure exhaust pipes are not heating surrounding areas excessively. If leaks or corroded areas are detected, shut the genera-

tor

set down and correct immediately.

Inhalation

of

exhaust gases can

l23FEEl

result in severe personal injury or

death. Inspect exhaust system audibly and visually for

leaks daily. Repair leaks immediately.

WIRING

Verify that all wiring connections are tight and hooked up properly. Check each of the following:

@

Load Wires

0

Control Wires Ground Strap

Battery Cables

10-1

FUEL

SYSTEM

With the generator set operating, inspect the fuel supply line, filter, and fittings for leaks. Check any flexible sections for cuts, cracks and abrasions and make sure they are not rubbing against anything that could cause breakage.

Leaking fuel will create a fire hazard

-1

which can result

in

severe personal

injury or death if ignited by

a

spark. If leaks are detected, shut generator set down and correct leak immediately.

CONTROL

Stop and start the generator set several times at the set control and remote control (if equipped) to verify the control functions properly.

Y

MECHANICAL

Stop the generator set and inspect

for

leaking gaskets,

loose fasteners, damaged components, or interference problems. Repair as required. Inspect the generator set compartment and verify thereare no breaks or openings

in

the vapor-proof wall that separates the compartment

from the coach interior. Seal openings as required.

10-2

r

A

I

Onan Corporation

1400

73rd Avenue

N.E.

Minneapolis,

MN

55432

612-574-5000 International

Use

Telex: 275477

Fax: 612-574-8087

Onan is a registered trademark

of

Onan Corporation

1-800-888-ONAN