Kohler l654 Service Manual

RV GENERATOR

SERVICE MANUAL

3.5KW-7.5KW

(with relay controller)

KOHLER -

GENERATORS ,.’

Table of Contents

Page

Safety Precautions . . . . . . . . . . . . . . . . . . . . . . .

i

Section 1. Introduction and Specifications

l-l.
l-2.
l-3.
l-4.
l-5.
1-6.
l-7.
1-8.
1-9.

Introduction

............................. l-l

Model 3.5 CM21-RV

...................... l-l

Model 4.5 CM21-RV (single)

.............. l-l

Model 4.5CKM21-RV (twin)

............... 1-I

Model 5.5 CM21-RV

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

l-l

Model 7 CM21-RV

........................ l-l

Model 7.5 C21-RV

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

1-2

Oil Specifications

........................ l-4

Fuel Specifications

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

l-5

Section 2. Operation

2-1. General.

......................... 2-1

2-2. Prestart Checklist

................... 2-1

2-3.

Operation

........................ 2-l

Section 3. Scheduled Maintenance

Governor

3-1.

General.

......................... 3-1

3-2.

Scheduled Maintenance

............... 3-I

Section 4. Troubleshooting

4-l. General.

........................ .4-l

4-2.

RV Systems Check

.................. 4-1

4-3. Troubleshooting

.................... 4-2

Section 5. Relay Controller

5-l.
5-2.

5-3.
5-4.
5-5.

Description

....................... 5-1

Sequence of Operation

............... 5-l

Fuses

........................... 5-4

REl Diode

....................... 5-5

Relays

.......................... 5-5

Page

Section 6. Generator

6-l. General

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

6-1

6-2. Troubleshooting .................... 6-1

6-3. Generator Disassembly ............... 6-l

6-4. Build-up Circuit

.................... 6-7

6-5. Brushes .......................... 6-8

6-6. Slip Rings

........................ 6-9

6-7. Exciter / Voltage Regulator ............ 6-9

6-8. Stator .......................... 6-I 1

6-9. Rotor. ......................... 6-11

6-10. Separate Field Excitation ............. 6-11

6-11. Voltage Sensing Relay ............... 6-12

6-l 2. Generator Reassembly ............... 6-12

Section 7. Choke, Shutdown Control and

7-1.

7-2.

7-3.
7-4.
7-5.
7-6
7-7.
7-8.
7-9.

Choke Testing and Adjustments

(3.5kW,4.5kW). . . . . . . . . . . . . . . . . . . . 7-1

Choke Testing and Adjustments

(4.5 twin, 5.5,7, 7.5kW) . . . . . . . . . . . . . 7-3

Positive Shutdown Control (3.5kW-7kW) . . . . 7-3

Crankcase Breather (3.5kW, 4.5kW) . . . . . . . 7-4

Governor (3.5kW, 4.5kW single). . . . . . . . . . 7-4

Governor Hunting Checks (4.5kW Only) . . . . 7-5

Governor (4.5kW twin). . . . . . . . . . . . . . . . 7-6

Governor (5.5kW, 7kW) . . . . . . . . . . . . . . . 7-6

Governor (7.5kW) . . . . . . . . . . . . . . . . . . . 7-7

Section 8. Wiring Diagrams

Appendix

Radio Frequency Interference Kit.. . . . . . . . . A-l

Safety Precautions

A Generator Set, like any other electro-mechanical device
can pose potential dangers to life and limb if improperly
maintained or imprudently operated. The best safeguards
against accident are to be ever mindful of the potential
dangers and to always use good common sense. In the
interest of safety, some general precautions relating to
operating of a Generator Set are presented below. Keep

these in mind.

A

WARNING

LETHAL EXHAUST GAS! An engine discharges deadly

carbon monoxide as part of the exhaust when operating.

Carbon monoxide is particularly dangerous in that it is an
odorless, tasteless, and nonirritating gas, but be ever
mindful that it can cause death if inhaled for even a short
period of time. Have only qualified specialists install and
replace exhaust system components and have the system
inspected frequently. Be careful when parking your coach
to avoid obstructing the exhaust outlet. The exhaust
gasses must discharge freely, otherwise carbon monoxide
may deflect under and into the vehicle or enter through
open doors, windows, or vents. Also make sure that your
exhaust cannot be discharged toward neighboring RV’s,
campers, or any occupied building. Be especially watchful

for exhaust accumulation under calm, windless condi­tions.

A

WARNING

ELECTRICAL SHOCK! Battery can cause electrical burns

and shocks. Exercise reasonable care when working near
the battery to avoid electrical connections through tools.
Remove wristwatch, rings, and any other jewelry.

A

WARNING

HIGH VOLTAGE! Remember that the function of a genera-

tor set is to produce electricity and that wherever electric­ity is present, there is the potential danger of electrocu­tion. Take the same precautions with electrical appliances
in your coach that you would observe in your home. Keep
away from electrical circuits and wiring while the set is
running and have electrical service performed only by
qualified electricians. Make sure unqualified persons,
especially children, cannot gain access to your set - keep
the compartment door locked or securely latched at all
times. Be sure that generator is properly grounded. Never
touch electrical leads or appliances with wet hands, when
standing in water, or on wet ground as the chance of
electrocution is especially prevalent under such con­ditions.

A

WARNING

UNIT STARTS WITHOUT NOTICE! To prevent accidental

starting on units with a remote start/stop switch, always
disconnect battery (remove negative lead first and recon­nect it last) to disable generator set before working on any
equipment connected to generator.

A

WARNING

DANGEROUS ACID! Avoid contact with battery electro-

lyte. It contains acid which can eat holes in clothing, burn
skin, and cause permanent damage to eyes. Always wear
splash-proof safety goggles when working around the
battery. If battery electrolyte is splashed in the eyes or on
skin, immediately flush the affected area for 15 minutes
with large quantities of clean water. In the case of eye
contact, seek immediate medical aid. Never add acid to a
battery once the battery has been placed in service. Doing
so may result in dangerous spattering of electrolyte.

.A WARNING

EXPLOSIVE t3ATTERY GASES! The gases generated by a
battery being charged are highly explosive. Do not smoke

or permit flame or spark to occur near a battery at any
time, particularly when it is being charged. Avoid contact­ing terminals with tools, etc., to prevent burns and to
prevent sparks that could cause an explosion. Remove
wristwatch, rings, and any other jewelry before handling
battery. Any compartment containing batteries should be

...

well ventilated to prevent accumulation of explosive gases.
To avoid sparks, do not disturb battery charger connec­tions while battery is being charged and always turn
charger off before disconnecting battery connections.
Turn automotive test equipment off when connecting or
removing battery clips. When removing or reconnecting
battery cables, make sure ignition switch and all accesso­ries are turned off.

A

WARNING

EXCESSIVE NOISE! Never operate without adequate

muffler or with faulty exhaust system - exposure to
excessive noise is not only tiring but can lead to impair­ment of hearing.

A

WARNING

HOT PIPING! An engine gets hot while running and

exhaust system components get extremely hot. Do not
work on generator set until unit is allowed to cool.

A

WARNING

DANGEROUS FUELS! Use extreme caution when hand-

ling, storing, and using fuels - all fuels are highly
explosive in a vapor state. Store fuel in a well-ventilated
area away from spark producing equipment and out of the
reach of children. Never add fuel to the tank while the
engine is running to prevent spilled fuel from igniting on
contact with hot parts or from ignition spark. Keep fuel
lines and connections tight and in good condition - don’t
replace flexible fuel lines with rigid lines. Flexiblesections

are used to avoid breakage due to vibration. Should any
fuel leakage, fuel accumulation, or electrical sparks be
noted, DO NOT OPERATE GENERATOR SET. Have sys-

terns repaired by qualified specialists before resuming
generator operation. Additional precautions should be
taken when using the following fuels:

Gasoline-Store gasoline only in approved red containers
clearly marked GASOLINE. Don’t store gasoline in .any
occupied building.

Propane (LP)-Adequate ventilation is mandatory. Pro-
pane is heavier than air; install gas detectors low in room.
Inspect detectors often.

A

WARNING

UNINTENTIONAL STARTING! To prevent accidental

starting when checking choke operation, remove spark
plug lead(s) at spark plug(s).

A

WARNING

FLASH FIRE! A sudden flash fire can cause serious burns.

To avoid the possibility of a flash fire, do not smoke or
permit flame or spark to occur near carburetor, fuel line,
fuel filter, fuel pump, or other potential sources of spilled
fuel or fuel vapors.

A

WARNING

ELECTROCUTION! Your RV generator set must not be

used to “backfeed” by connecting it to building/camp­ground electrical circuits. Doing so can cause serious
injury or death to utility personnel working on utility
transmission lines and may also seriously injure persons in
your household. Unauthorized connection may be unlawful
in some states and/or localities. A transfer switch must be
installed in the RV to prevent interconnection of generator
and outside source of power.

A

WARNING

BACKFIRE! A sudden backfire can cause serious burns.

Keep hands and face away from the carburetor when the
air cleaner is removed.

A

WARNING

FIRE HAZARD! Keep the compartment and generator set

clean and free of debris to minimize chances of fire. Also
remember that hot exhaust gases and exhaust system
parts could start grass fires. Keep away from hot engine
and generator parts’to avoid burning yourself.

A

WARNING

MOVING PARTS! Do not open generator set compartment

door when unit is running, except for servicing by quali­fied specialists. Replace guards, covers, and screens (if
used) before operating generator set.

A

WARNING

HIGH VOLTAGE! When the power cord is plugged in

during voltage regulator test, the AC pins become “hot”
and there is danger of electrocution.

A

WARNING

EXPLOSION! Use generator sets specified for RV use in RV

installations only.

Section 1.

Introduction and Specifications

l-l. INTRODUCTION

This manual covers operation, scheduled maintenance
troubleshooting and corrective maintenance for Kohler gen­erator sets designed and built for recreational vehicles. The

six standard models are the 3.5CM21 -RV, 4.5CM21-RV,

4.5CKM21 -RV, 5.5CM21 -RV, 7CM21 -RV and 7.5C21 -RV.
These models are referred to by their kilowatt output,

3.5kW, 4.5kW (single), 4.5kW (twin), 5.5kW, 7kW and

7.5kW. Differences between models are noted throughout

the manual. All models feature Kohler designed and built
4-cycle gasoline engines, rotating field generators and relay

controllers. See Table l-l for specifications and model vari­ations, Table 1-2 for dimensions and weight, and Table l-3

for engine specifications. Refer to the wiring diagrams in

the back of the manual.
I-2. MODEL 3.5CM21-RV
The 3500 watt generator set is powered by a single

cylinder model K181 QS engine. The set produces 120 volt,
29 amp alternating current. It has a rotor with two
magnetic poles and operates at 3600 R.P.M., producing 60
hertz or 3000 R.P.M., producing 50 hertz, 13 amp current.
A 30 amp circuit breaker protects the set from overload
damage. Due to its compact size and lightweight, it is
installed in RV’s with limited suspension support and
compartment space. See Figure l-l for major components.

1-3. MODEL 4.5CM21-RV

The 4500 watt generator set is powered by a single
cylinder Kohler Model K341QS engine. The set produces

Model

3.5CM21-RV

3.5CM61-RV

3.5CFM21-RV

3.5CFM61-RV

4.5CM21:RV

4.5CM61 -RV

4.5CFM21-RV

4.5CFM61-RV

4.5CKM21 -RV

4.5CKM61 -RV

5.5CM21

5.5CM61

5.5CFM21

5.5CFM61
7CM21
7CM61

7.5C21

7.5C61

Volts

Amps Per

Term in al Watts Freq. (HZ) RPM

120

29

3500 60 3600

120/240

14.5 3500 60

3600

120

26.6

3200 50

3000

120/240

13.3

3200

50

3000

120

37.5 4500 60

1800

120/240 18.8

4500 60 *

1800

120

30

3600 50 1500

120/240

15

3600

SO

1500

120 37.5 4500 60

1800

1201240

18.8

4500 60

1800

120

46

5500 60

1800

120/246 23 5500 . 60 1800

120 37.5 4500 50 1500

120/240

18.8 4500 ,50 1500

120 58

7000 60 1800

120/240 26

7000

60 ’ 1800

120

62.5

7500

60 1.800

120/240

31.3 7500

60 1800

120 volt, 37.5 amp alternating current. It has a rotor with
four magnetic poles and operates at 1800 R.P.M., produc­ing 60 hertz. A 40 amp line circuit breaker protects
generator against damage due to overload. See Figure l-2
for major components.

1-4. MODEL 4.5CKM21-RV

The 4500 watt generator set is powered by a two cylinder
Kohler Model KT17 engine. The set produces 120 volts,

37.5 amp alternating current. It has a rotor with four mag­netic poles and operates at 1800 R.P.M., producing 60
hertz. Two 20 amp circuit breakers protect against damage
due to overload. See Figure l-3 for major components.

1-5. MODEL 5.5CM21-RV

The 5500 watt generator set is powered by a two cylinder
Kohler Model K582QS engine. The set produces 120 volt,
46 amp alternating current. It has a rotor with four magne-

tic poles and operates at 1800 R.P.M., producing 60 hertz.

A 50 amp circuit breaker (on most models) protects against
damage due to overload. See Figure I-4for major compon­ents.

1-6. MODEL 7CM21-RV

The 7000 watt generator set is powdered by a two cylinder

Kohler Model K582QS engine. The’set produces 120 volt,
58 amp alternating current. It has a rotor with four magne­tic poles and operates at 1800 R.P.M., producing 60 hertz.
A 60amp circuit breaker (on most models) protects against
damage due to overload. See Figure I-4for major compon­ents.

. .

Wires, I

2
3

‘2

3
2
3
2
3
2
3

2
3
2
3
2
3

2
3

Phase

1

1

1

1
1
1
1
1

1
1

1
1
1
1
1
1

1
1

Table l-l. Generator Specifications

l-l

1-7. MODEL 7.5CZl-RV

The 7500 watt generator set is powered by a four cylinder

Kohler Model L654 liquid-cooled engine. Two 30 Amp
circuit breakers protect the rotating field 60 Hertz genera-

torfrom overload. On the 7.X21 model-s, the set produces

120 volt, 62.5 amp alternating current. On the 7.5661
models, 120/240 volt, 31.3 Amp alternating current is
produced. See Figure 1-5 for major components.

Specification

Weight (approximate)

3.5 Model

150 lb.

(68.0 kg)

4.5 Model
(Single)

235 lb.*

(106.6 kg)

,

4.5 Model

KT17

Series II

5.5 Model 7.0 Model

7.5 Model

4

230 lb.**

315 lb. 334 lb.

470 lb.

(104.3 kg)

(142.9 kg)

(151.5 kg) (213.2 kg)

Length - Overall 22” 23- 13/26”

28-5/l 6”

26”

27-l/2”

43-l /4”

(55.9cm)

(60.5cm) (71.9 cm)

(66.Ocm)

(69.8cm) (109.8cm)

Width - Overall 13-3/4” 18-3/l 6” 1 20-3/4” 21-l/2”

(34.9cm) (46.2cm) 1 (52.7 cm)

(54.6cm)

Height - Overall 15-314” 19-l /I 6” 17-9/l 6”

20-3/8”

20-3/8” 25-l /4”

(40.0cm) (48.4cm) (44.6 cm)

(51.8cm)

(51.8cm) (64.1cm)

A

A

**KT17 Series I

*Earlier Models 250 I b.

235 lb. (106.3 kg)

(113.4 kg)

Table l-2. Dimensions and Weight

Specifications

Fuel Inlet Connection

Size

Battery Voltage
Battery Amp Hr.
Battery Ground

Battery Cranking

Current

3.5 Model

l/4” I.D.

12v

55

Negative

40 amps

4.5 Model
(Single)

l/4” I.D.

12v

55
Negative

76 amps

4.5 Model
(Twin)

7/l 6-20

U.N.F.

12v

55

Negative

76 amps

5.5 Model 7.0 Model

l/4” I.D. l/4” I.D.

12v

12v

55

55

Negative Negative

98 amps 98 amps

.

7.5 Model

7/l 6-20

U.N.F.

12v

90

Negative

120 amps

Battery Charging

Current

15 amps

7 amps

7 amps

7 amps 7 amps 4 amps

Engine Model

K181QS K34 1 QS KTI 7 K582QS K582QS L654

Breaker Point Gap

0.020” 0.016” to 0.012” to

0.020” 0.020” 0.015”

(0.51 mm)

0.020”

0.018”

(0.51 mm) (0.51 mm)

(.381mm)

(0.41 mm to

(0.30mm to

0.51 mm)

0.45mm)

RPM

3600 1800

1800

1800

1800

1800

Fuel System Choke

Automatic

Automatic

Automatic

Automatic Automatic

Automatic

Thermal/Electric Thermal/Electric Thermal/Electric Thermal./Electric Thermal/Electric Thermal/Electric

Spark Plug Gap

0.035” 0.035”

0 -025”

0.035” 0.035” .0.025”

(0.89mm)

(0.89mm)

(0.64mm) (0.89mm) (0.89mm)

(0.64mm)

Total Air

376cfm

396cfm

417cfm

675cfm

675cfm 1777cfm

Requirements ( 10.7m3/min.)

(11 .2m3/min.) (11 .7m3/min.) (19.1m3/min.)

(19.1 m3/min.) (49.75m3/min.)

Frequency Regulation

5% 5%

5%

5%

5% 5%

25% Load 0.35 gal/hr

0.52 gal/hr

0.40 gal/hr

0.55 gal/hr 0.56 gal/hr

0.7 gal/hr

g

(1.3 lts/hr) (2.0 lts/hr)

(1.5lts/hr)

(2.1 lts/hr)

(2.1 lts/hr)

(2.6 lts/hr)

._

‘;

5

50% Load

0.46 gal/hr 0.60 gal/hr

0.50 gal/hr

0.61 gal/hr

0.66 gal/hr 0.8 gal/hr

(1.7 lts/hr) (2.3 lts/hr)

(1 .9lts/hr)

(2.3 lts/hr)

(2.5 lts/hr)

(3.0 lts/hr)

v)
c

s

75% Load 0.57 gal/hr

0.73 gal/hr

0.60 gal/hr

0.73 gal/hr 0.84 gal/hr

1.1 gal/hr

z

(2.2 lts/hr) (2.8 lts/hr) (2.3lts/hr)

(2.8 lts/hr)

(3.2 Its/h r)

(4.2 Its/hr)

l? .

100% Load

0.74 gal/hr

0.92 gal/hr

0.80 gal/hr

0.88 gal/hr 1.08 gal/hr

1.4 gal/hr

I I

(2.8 Itslhr) I

(3.5 Its/hr)

I

(3.0lts/hr) I

(3.3 lts/hr) ,

(4.1 lts/hr) ,

(5.3 lts/hr) ,

Table 1.3 Engine Specifications

1-2

AIR COOLING

SPARK

SHROUD

REMOTE

CIRCUIT

CL

CONTROL PROTECTOR

CONTROLLER

(HIDDEN) I

INTAKE

BATTERY -+@ /

POSITIVE

CONNECTION

GROUND STRAP

AIR
EANER

BATTERY
CHARGING
RECTIFIER

REGULATOR

INTAKE

TIMING

SIGHT

HOLE

Figure 1-1. Service Side View of a Kohler 3500 Watt RV Generator Set

AIR

COOLING SHROUD

SPARK PLUG

DRY ELEMENT

AIR CLEANER

CIRCUIT

GOVERNOR

_

PROTECTORS\

REGULAT(

REMOTE
CONTROL
EC EPTAC L

iONTROLLER

START-STOP

SWITCH

BATTERY

POSITIVE

CONNECTION

I

STRAP

HARNESS PLUG

BREAKER POINT

FUEL

PUMP

AIR INTAKE

/ SCREEN

TIMING

SIGHT

HOLE

OIL FILL TUBE

AND DIPSTICK

,

AIR DISCHARGE

0lL DRAIN (UNDER UNIT)

Figure l-2. Service Side View of a Kohler 4500 Watt Single Cylinder RV Generator Set

BREATHER_

AIR DUCT

/

IGNITION

thtMtNT

EXHAUST

.d

~.

TUBE

..”

FUEL

LINE

i OIL FILL

CIRCUIT

?OTECTOR

FINS

VOLTAGE /
EGULATOR

c

&j \ FUEL

PUMP

COOLING SLOTS

/

EQUIPMENT

GROUND

$p”

.:’ ,::. : ,, :.:::::,A~

:i:::::

,:*.

r

“’ :

./: >::: ;,.. 1’

,;:z>

. . .

..,,,,,.

’ CONTROLLER

Figure 1-3. Service Side View of a Kohler 4500 Watt Twin Cylinder RV Generator Set

AIR CLEANER

.

CARBURETOR

UST
ES

CIRCUIT PROTECTORS

/

b=AA9TE CONTROL

ICEPTACLE

BREAKER POINT

COVER (ON

GOVENOR)

BATTERY

CHARGING

VOLTAGE

REGULATOR

GOVERNOR

EGULATOR

FULL-FLOW

OIL FILTER

CONTROLLER

OIL FILL TUBE

& DIPSTICK

‘OP

BLOWER

, Ah I I

HOUSING

/

SWITCH

GROUNDING

AIR

I

“ISCHARGE

BATTERY POSITIVE

Y

CONNECTION

MOUNTI

OIL DRAIN LOCATED

UNDER UNIT

Figure I-4. Service Side View of a Kohler 5500 or 7000 Watt RV Generator Set

I-4

l-8 OIL SPECIFICATIONS
Use high quality detergent oil of API (American Petroleum

Institute) service class SF. Select viscosity based on the
air temperature at the time of operation as shown below:

RECOMMENDED SAE VISCOSITY GRADES

!

I

I

I

I

I 1 I

'F -50 6

T 1 r I I

20

32 40 60 80 100

t

I I

T

I

I I

I

c-30 -20 -10

0 10 20 30 40

TEMPERATURE RANGE EXPECTED BEFORE NEXT OIL CHANGE

l

Straight 30 weight oil is preferred. If multi-viscosity is
used, be aware of the resulting increase in oil consump­tion and combustion deposits when used in temperatures
above 32’ F (0” C).

I

Using other than service class SF oil, or extending oil
change intervals longer than recommended could cause
engine damage which is not covered by the engine
warranty.
On a new engine, change the oil after the first five hours of
operation, and thereafter on K181QS and K341 QS change
oil every 25 hours. On KT17, K582QS and L654, change
oil every 50 hours.

I-9. FUEL SPECIFICATIONS
For best results, use only clean, fresh, regular grade
unleaded gasoline with a pump sticker octane rating of 87
or higher in the U.S.A. In countries using the Research

MODEL

CAPACITY

35kW

1 Quart (0.95 Iitres)

4.5kW (Single)

2 Quarts (1.89 litres)

4.5kW (KT17
Series I)

3.8 Quarts (3.6 litres)

4.5kW (KT17
Series II)

1.5 Quarts (1.4 litres)

5.5kW

4 Quarts (3.78 litres) (Additional

l/2 quart (0.47 litres) when filter

is replaced)

7kW

4 Quarts (3.78 litres) (Additional

l/2 quart (0.47 litres) when filter

is replaced)

7.5kW

5 U.S. Quarts (4.73 Iitres)

Unleaded is recommended since it leaves less combus-

tion chamber deposits. Regular grade leaded gasoline

may also be used; however, be aware that the combustion
chamber and cylinder head will require more frequent
service.

Use fresh gasoline to ensure it is blended for the season,

and to’ reduce the possibility of gum deposits forming
which could clog the fuel system. Do not use gasoline left

over from the previous season.

Gasohol containing no more than 10% ethanol can be

used if unleaded gasoline is unavailable. Never use gas-

ohol containing more than 10% ethanol or gasoline con-

Table 1-5. Oil Capacity

rating method, it should be 90 octane minimum.

taining methanol. Do not add oil to the gasoline.

RADIATOR FILL

\

SPARK

PLUGS

CRANKCASE

A

BREATHER

\ /I\\

(HIDDEN)

I

CIjRBURETOR

VALVE

TAPPET,

COVER

BELTTENSION
ADJUSTMENT

GOVERNOR

ADJUSTMEN

OIL PRE

GAUGE

/

/

OIL

FILL/CHECK

MOUNTING

I /

OIL PRESSURE

ADJUSTMENT

\

\

CONTROLLER

\

GROUN

FUEL

OIL

FUEL

DRAIN

STRAF

TRAY

SOLENOID

PUMP

C

REMO’

CONTR

:ONNEC

TE

OL

TOR

Figure 1-5. Service Side View of Kohler 7500 Watt RV Generator Set

c

l-5

Section 2

Operation

2-l. GENERAL

Operation of the generator set is controlled by a single
switch on the controller (Figure 2-l). This switch is a

momentary contact, three-position, start-run-stop switch.

It is spring loaded to return to the center (run) position
when released from either the start or stop position. This
switch must be held in the desired position until the unit

is running or has come to a complete stop. The controller

includes a keyed connector for starting and stopping the
set at an optional remote switch located inside the vehicle.

2-2. PRESTART CHECKLIST

Refer to Table 2-l for all prestart checks.

CHECK REQUIREMENT

Oil Level Near Full (Not Over)

Air Inlets Unobstructed
Compartment Clean
Air Cleaner Clean, Properly Installed
Air Shrouding

Tight, Proper Position

Exhaust System Unobstructed, Properly

lnstal led

Electrical Connections Clean and Tight

Table 2-I. Prestart Checklist

2-3. OPERATION

NOTE
If the generator set shuts itself down due to
high engine temperature or low oil pressure,
the cause must be located and eliminated
before the set can be restarted. Also, make
sure the circuit breaker(s) is in the “on” posi­tion so generator output is transferred to the
load.

CAUTION

In the event of a “false start”, that is, the en­gine gets up sufficient speed to disengage the
starter but fails to continue running, allow the
engine to come to a complete halt before
making a restart attempt. If the flywheel is
still rotating when the starter is engaged, the
starter pinion and ring gear will clash which
may damage the ring gear teeth.

Figure 2-I. Controller

‘I. Move the START-STOP switch on the controller to

START position and hold until the engine is running but

not more than 10 seconds. Normally the engine will start
within five seconds. If the engine does not start in 10 sec­onds, release the switch and wait a few seconds before mov­ing back to START position. This allows the choke to reset
in the full choke position.

2. Whenever possible allow a brief cooling period by run­ning the set at low or no load for a few minutes just prior
to shutdown. To stop, move the switch to STOP position
and hold until the set comes to a complete halt.

2-I

Section 3

Scheduled Maintenance

3-l. GENERAL
Scheduled maintenance is “preventive” maintenance.
Major repair can be avoided by correcting problems when
they are small. When performing maintenance, always
look for signs of potential trouble, such as loose connec­tions or dirty components. When running the set, listen for
any unusual noises.

NOTE - Oil Change

3-2. SCHEDULED MAINTENANCE
Refer to Table 3-1 for scheduled maintenance requirements.

Perform each function at the indicated time interval. For
each function, refer to the applicable paragraph for instruc­tions.

NOTE

On a new engine change the oil after the first
five hours of operation, and thereafter on
K181QS and K341QS change oil every 25
hours. On KT17, K582QS & L654 change oil
every 50 hours.

For maintenance work on engine components,
refer to the Kohler engine service manual

which covers the engine model.

Every

1

Before Every Every Every

.

Each

25 50

100 500

Function Startup Hours

Hours Hours Hours

.

Compartment - Remove dirt. Blow dry
compressed air through cooling inlets

(set running).

X

I

Air Inlet and Outlet - Clean.

X

Oil Level - Check.

X

Check Exhaust Pipe. X

I

Oil - Change.

See note above.

. Oil Filter - Change.

X

Air Cleaner Element - Clean

(change every 200 hrs.).

X

Fuel Sediment Bowl or Filter
(if equipped) - Remove and clean.

X

Clean Electric Fuel Pump Filter ­See owner’s manual.

X
Check Coolant Level In Radiator (7.5KW) X
Check Fan Belt Tension (7.5KW)

X
Spark Plug - Clean and regap.

X

Point Contacts - Service or replace.

X

Brushes and Collector Rings ­Check and service.

X

Ignition Timing -

Check and correct.

X

Rectifier

- Regulator - Check

condition and battery charging.

X

Alternator Stator - Check leads and
connections. X

Starting Motor - Check brushes &
commutator.

X

Engine External Surface - Clean screen,

cooling fins, block, oil fill area.

X

Valve Clearance

- Check and adjust

valve stems and tappets. X

I

Crankcase Breather - Check valve and
gaskets, clean filter, check hoses.

X

Cylinder Head - Remove, clean

and inspect.

X

.

Electric Fuel Pump - Service filter.

X

1-i: 50 hours.

Check Electrolyte Level in Battery

---_--.-_ . ..-_ _

Table 3-1. Scheduled Maintenance

3-1

Section 4

Troubleshooting

4-l. GENERAL

CAUTION

When troubleshooting a generator set, always consider the
simplest causes first. Narrow the problem down to a func­tional system, such as fuel or ignition. To operate efficient­ly, an engine must have sufficient fuel, a good ignition
spark and good compression. All adjustments must be
correct. For a generator to produce the required electricity,
all parts must be clean, all connections tight, and all com­ponents in working order. See Table 4-l for Engine Trou­bleshooting and Table 4-2 for Generator Troubleshooting.

4-2. RV SYSTEMS CHECK

The “RV Systems Check” is designed to check the electri­cal status of an RV generator set prior to connecting and
testing with the controller. If the generator does not check
out in each step, correct the malfunction before proceeding
to the next step.

Do not push the V.B.U. button after the “GEN
ON” lamp is on. Voltage regulator damage may
resu It.

CAUTION

Do not use the RV Systems Check as a replace­ment for the controller. The hi-temp and low
oil pressure switches will not shut the machine

down in the event of a malfunction. Generator

damage will result.

1. Make sure the battery is properly connected and oil is
at proper level.

CAUTION

Do not push the CRANK button after the en-

2. Check the three fuses in the RV Systems Check tester

gine is running. Starter damage will result.

(Figure 4-l). Replace any blown fuses.

RV

‘II I

SYSTEMS CHECK

GEN

POL. CRANK ON’ SAFETY

IGNITION

ON OFF

CRANK CHOKE

V. B.U.

“RV SYSTEMS CHECK”

CONNECT TO RV GENERATOR

*WIRING HARNESS PLUG

SWITCHES

“Ignition” -

Supplies battery voltage to ignition coil,
choke heater, fuel control solenoid, fuel valve
and fuel pump.

“Crank” -

Supplies battery voltage to starter relay.
Note: May be actuated with ignition switch on
or off.

“Choke” - Supplies battery voltage to choke plate

solenoid. Note: May only be actuated during
cranking.

“V.B.U.” -

Voltage Build Up, supplies battery vol-

tage to excite field.
VISUAL INDICATORS
“Pol” - Green -

Indicates battery polarity correct.

“GEN. ON” -. DOES NOT FUNCTION ON SETS

EQUIPPED WITH RELAY CONTROLLERS.

“Crank” - Amber -’

Indicates battery voltage signal

present during cranking.

“Safety Switch” - Amber - Indicates safety circuit

wiring correct. Operator must manually short
temperature switch to ground to obtain this

indication.

[Check Tester Fuses First In Case Of Malfunction 1

FUSES

15 AMP - IGN/CRK

1 AMP -CHOKE

3 AMP - V.B.U.

Figure 4-1. RV Systems Check

4-1

3. Remove the

12 pin connector

plug it into the

tester.

from the controller and NOTE

4. Observe the POL (polarity) lamp. Green light indicates
battery polarity is correct. If lamp does not light, check for
correct battery connection to the generator set.

NOTE

On 5.5kW, 7kW and 7.5kW sets the SAFETY
lamp will also be on. This indicates the low oil
pressure switch is functioning properly.

5. With the IGNITION switch in OFF position, press the

CRANK button. The CRANK lamp should light and the
engine should crank. If the lamp does not light, no voltage
from the battery is present.

On 5.5kW, 7kW and 7.5kW sets, the SAFETY
lamp will go off after the engine has reached

sufficient operating oil pressure.

IO. To check the high temperature cutout, low oil pressure
cutout and/or the oil level cutout for proper operation,
start the generator set and connect a jumper wire from the
cutout device to ground. The “amber” safety lamp should
light, indicating the protective circuit is functioning prop­erly.

11. If all checks are OK, connect the 12 pin connector to
the generator set controller.

If the 15 amp fuse blows, check for defective cranking
solenoid, fuel pump or fuel solenoid, ignition coil, choke
heater, fuel shutdown control or shorted wiring.

6. Remove the air cleaner cover to observe the choke plate

during the next step.

If the 1 amp fuse blows, check for defective choke sol­enoid or wiring.

7. Again, with the IGNITION switch in OFF position press

the crank button. While the engine is cranking, press the

CHOKE button to supply battery voltage to the choke

plate solenoid. Make sure the choke plate is functioning

properly. If not, see Section 7. Release the CRANK and

CHOKE buttons.

If the 3 amp fuse blows, check for shorted or grounded
generator rotor or defective voltage regulator.

8. With the IGNITION switch ON, start the engine, using
CRANK and CHOKE buttons as needed. If engine does not

start, see Engine Troubleshooting, Table 4-l. With engine
at operating speed, press V.B.U. (voltage build-up) button

momentarily. Check for generator output voltage. If no
output voltage is available, see Troubleshooting Gen­erator., Table 4-2.

9. Turn the IGNITION switch to OFF position to stop the
engine.

4-3. TROUBLESHOOTING

Refer to Table 4-l for engine troubleshooting. To make

engine repairs, refer to the Kohler engine service manual

which covers the engine model. A troubleshooting chart

cannot cover every possible cause of malfunction. Always
consider every possible cause of malfunction. Knowledge
of four cycle engines and battery ignition systems can
be applied. Refer to Table 4-2 to troubleshoot the genera­tor. The table refers to applicable paragraphs in the manual.

4-2

CONDITION

A. Hard Starting or Loss of Power

B. Overheating

C. Backfiring

D.

Occasional “skip” at High Speed

E. Operating Erratically

POSSIBLE CAUSE

1. Faulty Ignition.
a. Loose or grounded high tension or breaker point leads.

b. Improper breaker point gap and timing.
c. Defective breaker points.
d. Faulty spark plug or improper gap.

e. Faulty condenser or coil.

f. Weak battery.

2. Faulty Fuel System.
a. Gasoline not getting to carburetor.

A. Dirt or gum in fuel line.

B. Fuel pump faulty.
b. Dirt in carburetor.
c. Carburetor improperly adjusted.
d. Choke faulty or improperly adjusted.
e. Stale fuel.
f. Carbon build up.
g. Possible intake manifold vacuum leak.

3. Valve maintenance.

4. Defective Automatic Compression Release (ACR).

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

Insufficient available cool air.
Dirty air intake screen, shroud or cooling fins.

Stale fuel.

Fuel mixture too lean.
Improper ignition timing.
Engine overloaded.

Tight tappet clearance.

Insufficient hot-air discharge opening.
Loose or broken fan belt (7.5kW).

Low coolant level (7.5kW).
Too much lube oil.
Summer/Winter air baffle in wrong position.

‘I. Fuel mixture too lean.

2. Improper timing.

3. Valve “sticking”.

4. Possible intake manifold vacuum leak.

1. Spark plug gap too wide.

2. Improper carburetor setting or lack of fuel.

3. Wrong type spark plug. Use resistor type plug.

4. Improper timing.

5. Faulty condenser.

1:

2.

3.

4.

5.

6.

7.

8.

9.

IO.

Clogged fuel line.
Water in fuel.

Faulty choke control.
Improper fuel mixture.
Loose ignition connections.
Vacuum leaks in manifold or carburetor connection.
Vent in gas cap plugged.
Fuel pump faulty.

4CR installed upside down. Solenoid should be to the bottom.

Improper ground on anti-dieseling device.

Table 4-1. Engine Troubleshooting

Refer to Kohler Engine Service Manual for Repair.

defer to Generator Owner’s Manual for Adjustments.

4-3

CONDITION

1. Engine will not crank.

POSSIBLE CAUSE/CORRECTION (SECTION)

1. Battery cable connections reversed. (Must be negative ground.)

2. 10 amp fuse in controller blown (5-3).

3. Defective start switch or “C” relay (5-2).

4. Open circuit in wiring harness or connector.

5. Faulty starter motor.

6. Open circuit in REI diode (5-4).

7. Normally closed 3CR contacts, open (5-5).

8. Busted or loose ground strap.

2. Engine cranks but will not start.

1. Choke not operating or out of adjustment (7-1, 7-2).

2. Check fuel supply to carburetor.

3. Faulty fuel shut-down control (7-3).

4. Faulty fuel pump.

5. Dirty or stuck ignition points.

6. Faulty condenser.

7. Faulty spark plug.

3. Engine starts, then stops when
switch is closed.

8. 2CR relay not functioning. Must have battery voltage on positive
connection of ignition coil (5-5).

9. Fuel mixture. Replace.

1. No AC generator output.

2. Faulty 3CR interlock relay (5-5).

3. Faulty 4CR voltage sensing relay (5-5).

4. Faulty exciter voltage regulator (6-7).

4. No AC output.

1. Circuit breakers in the off position (2-3).

2. Generator brushes not making contact on slip rings (6-5).

3. Faulty build-up circuit. Battery voltage must be present at terminal
“B” of regulator during cranking (6-7).

4. Open connection in wiring harness or plug connector (5-2).

5. Faulty exciter voltage regulator (6-7).

6. Circuit protector tripping due to overload, reduce load.

5. Low output or excessive drop in
voltage (below 1 IO volts).

1. Generator set overloaded.

2. Engine rpm set too low (7-5 thru 7-9).

3. Faulty exciter voltage regulator (6-7).

4. Poor stator coil connections, use a clamp-on ammeter and check

each connection. .

6. High AC voltage (above 125 volts AC).

1. Faulty exciter voltage regulator.

2. Stator reconnected improperly.

7. Engine shuts down for no apparent
reason.

1. Generator set overheated

- improper installation. Refer to RV

installation manual or 75kW Owner’s Manual.

2. No fuel.

3. Oil level or oil pressure system failure.

4. Faulty shutdown solenoid.

8. Unit will not operate with remote
switch - OK at controller.

I. Incorrect wiring of remote switch to remote plug assembly. Center

pole of remote switch must connect to terminal 4 of remote harness
plug, Figure 5-2.

2. Open connection in wiring.

Table 4-2. Troubleshooting Generator

Section 5

Relay Controller

5-I. DESCRIPTION

All generator set functions are dependent upon the control-

ler. See Figure 5-l for parts identification. For operation
instructions refer to Section 2. The controller includes a
keyed connector for installing a remote switch and hour­meter panel. This optional remote switch allows the oper­ator to start and stop the generator set from another loca­tion in the vehicle. The hourmeter records the hours of
generator set operation (Figure 5-2). The controller can be
removed by removing the two snap connectors and two
capscrews underneath the controller. This section covers
sequence of operation, and fuse, diode, and relay replace­ment.

5-2. SEQUENCE OF OPERATION

The Relay Controller is the controlling point for generator
set operation. The following is the sequence of operations
controlled by the Relay Controller. See Figures 5-3
through 5-7.

.

REMOTE CONTROL

/

WIRING HARNESS

CONNECTOR

PLUG

IGNITION RELAY

REI

3CR

DIODE INTERLOCK RELAY

Figure 5-1. Controller

12 VOLT

GENERATOR

“ON” LIGHT

12 VOLT

HOURMETER

Lead Designation

. .

Pin No. Color Gauge of Wire

1 Red

18

2 White

22

3 Brown

22

4 Black

18

5

6 Blue

22

REMOTE CONTROL CONNECTOR

(ON CONTROLLER)

HARNESS

/

PLUG

SPRING LOADED

START-STOP

APPLIES TO SWITCH A-269299 ONLY

KOHLER PART NO. PA-269966

Figure 5-2. Remote Control Connections

5-l

l lO AMP

lN.LINE

FUSE

I

CHOKE HTR.

ZCR

I I

*EARLIER MODELS ONLY

238760

\;/-

.

d

2CR

8 /

*EARLIER MODELS ONLY

238749

Figure 5-3. Sequence of Operation

Schematic 3.5kW

Figure 5-4. Sequence of Operation

Schematic 4.5kW (Single)

52

5 II

-STARTER 1

REuOTE SW.

+
YLL

2CR

2 + ICN -

EINTS

OIL

e

II

LIITLUI I

BREAKER

4

“EARLIER MODELS ONLY

277948

STD. ON 7kW

OPTION 5.5kW

. :

Q%. Qb +O-.

.

I, 1

.

.

*EARLIER MODELS ONLY

277931

Figure 5-5. Sequence of Operation

Schematic 4SkW (KT17 Series I)

Figure 5-6. Sequence of Operation

Schematic 5.5 & 7kW

5-3

I2 VOLT

3CRT

La?-

FUEL ‘PUMP

.

I

TRANSFORMER

Y

r

CEN:: ATOR

i t

L2 LI

LO

“EARLIER MODELS ONLY

241753

Figure 5-7. Sequence of Operation

Schematic 7.5kW

1. Pressing the start-stop switch to the start position ener­gizes both the cranking contactor “C” and the 2CR relay.
(Diode REI will prevent this from happening if the battery
is connected in reverse.)

5-4

2. Energizing the 2CR relay will allow current to flow
through the 10 Amp in-line fuse to the ignition coil, choke
heater, carburetor shut-down solenoid and electric fuel
pump (if equipped).

3. Energizing cranking contactor “C” will allow current to
flow to the starter motor and crank the engine. The car­buretor choke solenoid will also be energized and current
can flow through the normally closed 4CR contacts to the
“B” terminal of the aenerator voltage regulator for the
initial voltage build-up.

4. When the engine starts and the generator is producing
AC output, the 4CR relay (mounted in the generator end
bracket) will energize.

5. The normally CLOSED contacts in the V.B.U. (voltage

. .

bui,ld-up) circuit will then open and disconnect the battery
supply from the generator voltage regulator.

6. The normally OPEN 4CR contacts will close and allow
the 3CR relay to become energized. All the 3CR contacts
will then change positions, the normally open contacts
will close and the normally closed contacts will open.

7. The normally closed 3CR contacts in series with the
“C” cranking contactor will open deenergizing the “C”
contactor. This offers protection from engaging the starter
motor while the unit is operating.

8. The 3CR contacts in series with the 2CR relay coil will
close, maintaining current flow to the 2CR relay coil.
The 2CR relay controls current flow to the engine ignition
circuit.

9. The now closed 3CR contacts in series with the ICR
relay coil and engine safety cutouts will allow the ICR relay
to become energized if the safety cutout contacts close.
The ICR relay also energizes when the start-stop switch is
placed in the stop position.

10. Energizing the ICR relay, either by the engine safety
cutouts or by placing the start-stop switch to the stop posi­tion will disrupt current flow to the 2CR relay coil and in
turn prevent current flow to the ignition circuit when the
2CR contacts in this circuit open.

5-3. FUSES

A

WARNING

UNIT STARTS WITHOUT NOTICE! To prevent accidental

starting on units with a remote start/stop switch, always
disconnect battery (remove negative lead first and recon­nect it last) to disable generator set before working on any
equipment connected to generator.

There is one IO Amp fuse inside the controller (Figure 5-l).
This fuse protects the controller against damage in the

event a short develops in the engine wiring. If this fuse
“blows” the set will stop. If the set has stopped due to

causes other than lack of fuel, engine malfunction, or low

oil pressure, remove the cover of the controller and check
the fuse. If blown, replace the fuse then attempt to restart
the generator set. If the set will not start, or if the fuse

blows again, locate and correct the cause.