Onan GRCA Service Manual

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Printed in U. S. A.

Installation Manual

GRCA

184-0177

July, 2004

Service Manual

Redistribution or publication of this document,

by any means, is strictly prohibited.

Supplement 965−1081
Date: 12-2004
Insert with-

Titles: GRCA Installation Manual

GRCA Service Manual

Numbers: 184−0169, dated May, 2004

184−0177, dated July, 2004

This supplement updates the GRCA Installation Manual and GRCA Service Manual to include infor­mation on the RSZ transfer switch time delay relay.

TIME DELAY RELAY

Beginning in April of 2004, GRCA generator
sets include a transfer switch time delay relay.

This relay eliminated a loss of start signal that
sometimes occured on earlier models during
transfer from normal to emergency power.
Without this relay, the genset may not start as
commanded during a loss of power or when
testing the transfer switch.

If your genset does not include this relay, kit
307−3040 can be purchased separately.

NOTE: The wiring diagram provided with the

transfer switch shows connections of
this relay to a genset, incorrectly indi­cating that terminals 1 and 5 are nor­mally open contacts. As shown in the
illustrations, the normally open con­tacts are terminals 5 and 6.

CHANGES TO MANUALS

GRCA Installation Manual (184−0169) − Replace Figures 7-3, 7-4, 7-5, and 7-6 with the attached
pages.

GRCA Service Manual (184−0177) − Replace page 11-2 with the attached page.

Page 1 of 7

Page 2 of 7

7-3

No. 306-4692 Sh 2 of 2
Rev. C Mod Sys: Pro-E
Modified 7/2004

WITH TIME DELAY RELAY

FIGURE 7-3. RSZ 100-AMP NEMA-1 TRANSFER SWITCH

7-4

No. 306-4693 Sh 2 of 2
Rev. C Mod Sys: Pro-E
Modified 7/2004

WITH TIME DELAY RELAY

RSZ 200-AMP NEMA-1 TRANSFER SWITCH

7-5

No. 306-4694 Sh 2 of 2
Rev. C Mod Sys: Pro-E
Modified 7/2004

WITH TIME DELAY RELAY

RSZ 100-AMP NEMA-3R TRANSFER SWITCH

7-6

No. 306-4695 Sh 2 of 2
Rev. C Mod Sys: Pro-E
Modified 7/2004

WITH TIME DELAY RELAY

RSZ 200-AMP NEMA-3R TRANSFER SWITCH

No. 630-2252 Sh 1 of 6
Rev. D Mod Sys: Pro-E
Modified 6/2004

TIME DELAY RELAY

TIME
DELAY
RELAY

ADD

WIRE

5

NO Contacts
To Genset Remote
Start Terminals

6

Battery Positive (+)

Battery Negative (−)

Genset & Charger
Battery Positive

(+)

Genset & Charger
Battery Negative

(−)

TRANSFER SWITCH INTERCONNECTION WIRING DIAGRAM

11-2

Table of Contents

i

SECTION TITLE PAGE

SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

2 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1

3 OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Engine Oil Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Starting Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Fuel Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Fuel Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Genset Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2

Starting and Stopping the Genset . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4

Powering Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–5

Varying Operating Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–8

Genset Break–In. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–9

Genset Exercise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–9

Genset Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–9

4 PERIODIC MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–1

General Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–2

Checking Engine Oil Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3

Changing Engine Oil and Oil Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . 4–4

Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–5

Spark Plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6

Battery Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–7

5 PREPARATIONS FOR SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Special Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–2

Removing and Installing the Housing Panels. . . . . . . . . . . . . . . . . . . 5–3

Accessing the Engine for Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5

Redistribution or publication of this document,

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Redistribution or publication of this document,

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SECTION TITLE PAGE

6 ENGINE SUBSYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1

Cylinder Compression Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1

Valve Clearance (Lash) Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . 6–2

Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3

Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–4

Magnetic Pickup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5

Governor Rod and Actuator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–6

Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–8

7 GENERATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

Servicing Brushes and Slip Rings . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–2

Generator Disassembly/Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–3

Testing the Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–8

8 GENSET CONTROL PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

9 GOVERNOR CONTROLLER BOARD (A12) . . . . . . . . . . . . . . . . . . . . 9–1

10 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1

Status/Diagnostics Light on the Genset Control Switch. . . . . . . . . . 10–1

Fault Code Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1

Displaying Level One/Two Fault Codes . . . . . . . . . . . . . . . . . . . . . . 10–1

11 WIRING DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1

ii

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

The following symbols in this manual alert you to
potential hazards to the operator, service person
and equipment.

alerts you to an immediate hazard
which will result in severe personal injury or
death.

alerts you to a hazard or unsafe
practice which can result in severe personal
injury or death.

alerts you to a hazard or unsafe
practice which can result in personal injury or
equipment damage.

Electricity, fuel, exhaust, batteries and moving
parts present hazards which can result in severe
personal injury or death.

GENERAL PRECAUTIONS

• Keep ABC fire extinguishers handy.

• Make sure all fasteners are secure and
torqued properly.

• Keep the genset and its compartment clean.
Excess oil and oily rags can catch fire. Dirt
and gear stowed in the compartment can
restrict cooling air.

• Before working on the genset, disconnect the
negative (–) battery cable at the battery to
prevent starting.

• Use caution when making adjustments while
the genset is running—hot, moving or electri­cally live parts can cause severe personal
injury or death.

• Used engine oil has been identified by some
state and federal agencies as causing cancer

or reproductive toxicity. Do not ingest, inhale,
or contact used oil or its vapors.

• Do not work on the genset when mentally or
physically fatigued or after consuming alco­hol or drugs.

• Carefully follow all applicable local, state and
federal codes.

GENERATOR VOLTAGE IS DEADLY!

• Generator output connections must be made
by a qualified electrician in accordance with
applicable codes.

• The genset must not be connected to the
public utility or any other source of electrical
power. Connection could lead to electrocu­tion of utility workers and damage to equip­ment. An approved switching device must be
used to prevent interconnections.

• Use caution when working on live electrical
equipment. Remove jewelry, make sure
clothing and shoes are dry and stand on a
dry wooden platform.

FUEL IS FLAMMABLE AND EXPLOSIVE

• Keep flames, cigarettes, sparks, pilot lights,
electrical arc-producing equipment and
switches and all other sources of ignition well
away from areas where fuel fumes are pres­ent and areas sharing ventilation.

• Fuel lines must be secured, free of leaks and
separated or shielded from electrical wiring.

• Leaks can lead to explosive accumulations of

gas. Natural gas rises when released and
can accumulate under hoods and inside
housings and buildings. LPG sinks when
released and can accumulate inside hous­ings and basements and other below-grade
spaces. Prevent leaks and the accumulation
of gas.

iii

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▲

DANGER

!

▲

WARNING

!

▲

CAUTION

!

Safety Precautions

ENGINE EXHAUST IS DEADLY!

• Learn the symptoms of carbon monoxide poi­soning in this manual.

• The exhaust system must be installed in
accordance with the genset Installation
Manual.

• Do not use engine cooling air to heat a room
or compartment.

• Make sure there is ample fresh air when
operating the genset in a confined area.

BATTERY GAS IS EXPLOSIVE

• Wear safety glasses and do not smoke while

servicing batteries.

• When disconnecting the battery cables,

always check for a battery charger and dis­connect it first then disconnect the negative
(–) battery cable.

• When reconnecting battery cables, always

reconnect the negative (–) battery cable after
the positive (+) cable, then reconnect the
battery charger to reduce arcing.

MOVING PARTS CAN CAUSE SEVERE

PERSONAL INJURY OR DEATH

• Do not wear loose clothing or jewelry near
moving parts such as fans.

• Keep hands away from moving parts.

• Keep guards in place over fans.

iv

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HS-1

ABOUT THIS MANUAL

This is the Service Manual for the Series GRCA
generator set (genset). Read and carefully
observe all of the instructions and precautions in
this manual. For quick reference, this manual
includes Operation and Periodic Maintenance,
which are also covered in the Operator’s Manual.

See the Parts Catalog for part identification num­bers. Genuine Onan® replacement parts are rec­ommended for best results. When contacting
Onan for parts, service or product information, be
ready to provide the model number and the serial
number, both of which appear on the genset
nameplate (Figure 1-1). (The serial number is in
the row marked “S/N”, just below the model num­ber. The last character of the model number is the
specification letter, which is important for obtain­ing the right parts.)

Improper service or parts replace­ment can lead to severe personal injury or
death and to damage to equipment and prop­erty. Service personnel must be qualified to
perform electrical and mechanical service.

Unauthorized modifications or
replacement of fuel, exhaust, air intake or
speed control system components that affect
engine emissions are prohibited by law in the
State of California.

See the Installation Manual for important recom­mendations concerning the installation and for a
list of the installation codes and standards for
safety which may be applicable.

1-1

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1. Introduction

▲

WARNING

!

▲

WARNING

!

12GRCA-4229

1-2

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THIS PAGE LEFT INTENTIONALLY BLANK

2-1

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2. Specifications

GENERATOR SET GRCA:

Fuel Type Natural Gas LP Vapor
Rated Power 9 kW 11 kW
Frequency 60 Hertz
Voltage 120/240 volts
Circuit Breaker Rating 2-Pole, 50 amperes
Speed 3600 RPM

FUEL CONSUMPTION: ft.

3

/ hr BTU/hr ft.3/ hr BTU/hr

Quarter load 72 74,736 38 97,166
Half-load 101 104,838 47 120,179
Threee Quarter Load 133 138,054 60 153,420
Full-load 184 190,992 73 186,661

Natural Gas Supply Pressure 7-11" WC (water column) (178–279 mm)

LP Supply Pressure (vapor) 9-13" WC (water column) (228-330 mm)
Gas Supply Connection 3/4 inch NPT 3/4 inch NPT

ENGINE: Honda GX670 90 Degree V-Twin, 4 Stroke, OH Valve 2 Cylinder,
Specifications available in your Honda Owners Manual

Bore 3.03 inch (77 mm)
Stroke 2.83 inch (72 mm)
Displacement 40.9 inch

3

(670 cc)
Oil Capacity (with filter)* 1.48 Qt (1.4 Liter)
Intake Valve Clearance (Cold) .006 + .001 inch (.15 +.02 mm)
Exhaust Valve Clearance (Cold) .008 + .001 inch (.20 +.02 mm)
Spark Gap .012 - .016 inch (.030 - .040 mm)

Cylinder compression pressure 85 - 114 lbf/in

2

(6.0 - 8.0 kg/cm2) at 500 rpm

CRANKING SYSTEM:

Nominal Battery Voltage (BCI, GP 26) 12 volts
Battery Cranking Capacity 530 CCA @ 0° F (-17° C)
Nominal Battery Charging Output 6 amperes
Fuse F1 (control B+ input circuit) 10 amperes

ENCLOSURE:

Control Features Lighted Run-Off-Auto Switch, Running Time Meter, 50 Amp UL Listed Circuit

Breaker, DC Control Fuse. Large User Connection Area

Enclosure Features Sound Attenuated Drip-Proof Design, less than 70 dBA at 23 ft. (7M), Easy Service

Access, Internal Starting Battery Tray and Tie-Down, Heavy Duty Exterior High

Performance Fluoropolymer Finish Coat System
Exhaust Silencer Exhaust Silencer, Insulated for Low Noise and heat
Installation Features Pre-Mounted UV Resistant Plastic Installation Base, Convenient Electrical and

Gas Supply Connections, Ground Anchor System for Base Included
Unit Dimensions 45 in (1143 mm) Length, 34 inch (864 mm) Width, 39 inch (986 mm) Height

(Including installation base)
Weight 575 Pounds (261 kg)
Sound Level at Full Load Less than 70 dBA at 23 ft. (7 m)

ENGINE PART TOLERANCES AND CLEARANCES

Refer to your Honda Owners Manual - Part # 0031-ZN1-6011

* See Periodic Maintenance for oil filling instructions.

-

-

-

-

2-2

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THREAD TORQUES

Bolt torques are in lb-ft (N-m)*
Rotor Through-Bolt 32.5 ± 2.5 (45 ± 3)
Stator Feet to Base 16-20 (22-27)
Adapter-Engine Mounting Screws 12 (16)
Adapter-Generator Mounting Screws 25-35 (34-47)
Rear Vibration Isolators

Center Screw 30-35 (41-47)

Flange to Drip Tray Screws 16-20 (22-27)
Stator Studs to Engine Adaptor Finger tight
Stator Nuts 30 (41)

Front Vibration Isolators

Center Screw 30-35 (41-47)

Flange to Drip Tray Screws 16-20 (22-27)

Engine to Mounting Plate 30-35 (41-47)
Skidbase to Pallet 16-22 (22-27)
Spark Plug 13 (18)

* - Use engine oil as a lubricant for all threads EXCEPT for spark plug and rotor through-bolt threads.

3-1

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Engine Oil Recommendations

Oil is a major factor affecting performance and
service life. Use 4-stroke automotive detergent oil
that is designed for engines operating on LPG or
NATURAL GAS.

(The table below are examples of oils that meet
Honda’s requirements for LPG/NATURAL GAS­fueled engines.) SAE 30 (API service classifica­tion SJ) is recommended for general use.
For operation in temperatures below 32

0

F (00C),
5W-30 sythetic oil may be used for easier starting.
Do not use 5W-30 synthetic oil when the air tem­perature is above 32

0

F (00C). Units are shipped

with 10W-30 Oil.

STARTING BATTERY

This genset has a 12 VDC starting battery and
control system. See Specifications in Section 2
for minimum battery requirements for genset
cranking.

FUEL RECOMMENDATIONS

Fuels are flammable and explo­sive and can cause severe personal injury or
death. Do not smoke if you smell gas or are
near fuel tanks or fuel-burning equipment or
are in an area sharing ventilation with such
equipment. Keep flames, sparks, pilot lights,

arc-producing equipment, switches, and all
other sources of ignition well away. Keep a
type ABC fire extinguisher handy.

NFPA Standard No. 58 requires all persons
handling and operating LP to be trained in
proper handling and operating procedures.

When natural gas is the required fuel, use com­mercially available natural gas fuel having a
methane content of at least 90 percent (by vol­ume).

When LP (liquified petroleum) is the required fuel,
use grade HD–5 or equivalent consisting of at least
90 percent propane. Commercial LP may contain
more than 2.5 percent butane, which can result in
poor fuel vaporization and poor engine starting in
ambient temperatures below 32° F (0° C).

Satisfactory performance requires that fuel be
supplied at a pressure within the range indicated
in Specifications.

High gas supply pressure can
cause gas leaks which can lead to fire and
severe personal injury or death. Gas supply
pressure must be adjusted to Specifications
in Section 2 by qualified personnel.

FUEL SELECTION

The natural gas/LP vapor genset leaves the fac­tory set up for natural gas. If the genset is to be
run on LP vapor it must be converted for use with
LP vapor. See NG/LP Vapor Fuel System in
Installation Manual.

A genset purchased to use natural gas or LP vapor
cannot be converted to use LP liquid.

Wrong fuel selection can result in
hard starting, poor genset performance, and
fault shutdown.

3. Operation

▲

WARNING

!

▲

CAUTION

!

▲

WARNING

!

GENSET CONTROL

Figure 3-1 shows the genset control panel. The
control features are as follows:

Control Switch – This is a three-position Run-
Off-Auto switch with a status/diagnostics light.

The Run and Off positions are for manual start­ing and stopping of the genset. The Off position is
also used for resetting the controller following a

fault shutdown. The Auto position is for remote
start or transfer switch control.

Status/Diagnostics Light – This is an LED (light
emitting diode) in the control switch. It blinks rap­idly during cranking. It blinks in a coded fashion to
indicate the nature of a genset shut down.
See Troubleshooting in Section 11.

Hour Meter – The hour meter records the total
running time of the genset. It cannot be reset.

3-2

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20 A FUSE

CONTROL SWITCH

RUN

OFF

AUTO

CIRCUIT BREAKER

STATUS/DIAGNOSTIC

LIGHT

HOUR METER

FIGURE 3–1. GENSET CONTROL

3-3

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by any means, is strictly prohibited.

FIGURE 3–2. GRCA GENSET

3-4

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by any means, is strictly prohibited.

STARTING AND STOPPING THE GENSET

Pre-start Checks

Perform the maintenance checks instructed in
General Inspection (See page 4-2). Service the
genset and make repairs as required if a fault
shutdown code displays (see Troubleshooting in
Section 11). Also, see Genset Break-In and
Genset Storage in this section before placing in
service a new or rebuilt genset or one that has
been in storage.

Manual Starting

Push the control switch to Run. The engine
should crank, start, and run up to governed speed
in approximately 15 seconds. The starter discon­nects automatically as the status light stops blink­ing.

If the engine does not start (after 20 seconds of
cranking), the starter disengages. See Trouble-
shooting in Section 11 if the engine does not start.

Check for fuel and exhaust leaks. Stop the genset
immediately if there is a fuel or exhaust leak and
have it repaired before continuing operation.

Whenever possible, allow the engine to warm up
for a few minutes before connecting the electrical
loads.

Manual Stopping

Push the control switch to Off. Whenever possi­ble, allow the engine to cool down with the elec­trical loads disconnected for a few minutes before
stopping the genset.

Failure to push the control switch
to AUTO before leaving the genset renders the
genset unavailable for automatic standby
service.

Automatic Starting and Stopping

Push the control switch to Auto for remote, auto­matic starting and stopping (transfer switch).

Automatic startup of the genset
while performing maintenance or service can
cause severe personal injury or death. Push
the control switch to Off and disconnect the
negative (–) battery cable from the battery to
keep the genset from cranking and starting
while working on it.

▲

WARNING

!

EXHAUST GAS IS DEADLY!

All engine exhaust contains carbon monoxide, an odorless, colorless, poisonous gas that can
cause unconsciousness and death. Symptoms of carbon monoxide poisoning include

• Dizziness • Nausea

• Headache • Vomiting

• Weakness and Sleepiness • Inability to Think Coherently

IF YOU EXPERIENCE ANY OF THESE SYMPTOMS, GET INTO FRESH AIR IMMEDIATELY. If symp­toms persist, seek medical attention. Shut down the genset and do not operate it until it has been
inspected and repaired.

The exhaust system is an integral part of the genset. Do not modify the exhaust system. Make
sure there is ample fresh air when operating the genset in a confined area.

▲

WARNING

!

▲

CAUTION

!

3-5

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POWERING EQUIPMENT

Genset Loading

How much electrical equipment (system load) can
be connected at one time depends upon how
much power is available from the genset (See
Specifications, Section 2) and the type of load
being supplied. If the genset is “overloaded,” it’s
circuit breaker trips or it’s controller shuts it down
or both.

Determine how much equipment can be operated
at one time by adding the power consumption rat­ings of the individual system loads that are likely
to be used at the same time. Compare the sum of
the loads to the kW (kilowatt) rating of the genset.
Note that 1 kW = 1000 watts. See Table 3-2
for power consumption of typical residential
appliances.

Note that when a genset is loaded nearly to full
power and one of the large motor loads (such as

an air conditioner) “cycles on,” an undervoltage or
under frequency fault shutdown (Code Numbers
13 and 15) could occur. The reason is that for a
brief moment, at startup, motors can draw up to
three or more times their rated power consump­tion. You may, therefore, have to consider shut­ting off some loads at times when large motor
loads are “On.” When powering large motor loads
(such as an air conditioner) it is recommended
that the total load should not exceed 80% of the
genset kW rating.

Operating at High Altitude or High
Temperature

Air density is less at higher altitudes, resulting in
less available engine power. Power decreases
approximately 3.5 percent of rated power each
1000 feet (305 meters) of increase in elevation
above sea level. Power also decreases approxi­mately 1.5 percent each 10°F (5.5°C) increase in
ambient temperature above 77°F (25°C).

3-6

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TABLE 3–2. TYPICAL APPLIANCE POWER CONSUMPTION

Appliance Typical Watts Basic Loads Loads Chosen

Basic Needs

Electric Lighting - N=Number of 100 W Bulbs N 100 W Bulbs N x 100 =

Furnace - Gas 750

Electric Heat (See Heater Nameplate) 2000-5000

Well Pump - 1/2 HP 1000

Well Pump - 1 HP 2000

Refrigerator - 20 Cu. Ft. 800

Heat Pump 5000

Electric Water Heater 5000

Security System 20

Freezer - 20 Cu. Ft. 550

Sump Pump 1/3 HP 500

Garage Door Opener - 1/3 HP 500

Garage Door Opener - 1/2 HP 720

Typical Discretionary Loads

Microwave Oven - 800 Watt 1200

Microwave Oven - 1000 Watt 1500

Coffee Maker 900

Dishwasher 1400

Toaster 900

Computer 250

Electric Range - Two Burners 2900

Electric Range - Oven 7500

TV - 13” Color 70

TV - 32" Color 170

VCR 60

Stereo System 140

Electric Iron 1100

Electric Clothes Dryer 6000

Gas Clothes Dryer 720

Washing Machine 1000

Electric Hair Dryer 1600

Air Conditioner - 1 Ton 2000

Air Conditioner - 2 Ton 3000

Window A/C - 17,800 BTU 2000

Ceiling Fan 100

Vacuum Cleaner 780

Central Vacuum 1750

Total Basic Loads:

Total Chosen Loads:

Total Power Requirement:

How To Use the Table

Table 3-2 lists the typical power consumption of
some common household appliances. The value
in the table is a typical value, check the value on
the nameplate of your appliance for the most
accurate value. Also, you may want to use appli­ances that are not listed in the table. In that case,
use the value on the nameplate of the appliance
for its power consumption. For the most accurate
genset loading, substitute the values from the
nameplates on the appliances for all calculations.

Select the appliances that satisfy your basic
needs and write the power consumption in the
Basic Loads column. Add the power consumption
of all Basic Loads and place it in the Total Basic
Loads box at the bottom of the table.

Compare the Basic Loads Total with the rated
output of the genset. If the genset still has addi­tional capacity (that is the Basic Loads Total is
less than 80% of the genset capacity), you can
select additional loads from the list. Write the
power consumption of these additional loads in
the Loads Chosen column. Add the power con­sumption of all Chosen Loads and place it in the
Total Chosen Loads box at the bottom of the
table. You can add loads to the Basic Loads until
you reach 80% of the genset capacity.

Example

Using the chart on the previous page for a genset
rated at 10 kW. Select a total load less than 8kW
(8000 watts) in order to operate within the 80% limit.

Well Pump (1/2 HP) 1000

Refrigerator 800

Air Conditioner (2 ton) 2000

10 100 watt Bulbs 1000

Sump Pump (1/3 HP) 500

Microwave Oven (1000 W) 1500

Coffee Maker 900

Total 7700

This example uses 7700 watts. You could still
safely use a TV, a small appliance, or even your
computer before you exceed the 80% limit.

Remember that some loads are intermittent. For
example your refrigerator does not run constantly.
However, as it starts it requires considerably
more current than when it is running. For the sake
of the calculation from the table assume that all
loads are constant. If total power consumption
exceeds genset power output, the genset may
shut down. In this case, you may have to operate
some loads in sequence, one after another, rather
than all at the same time.

If the load on the genset exceeds the rated capac­ity of the genset, the genset shuts down. If the
genset shuts down under load, remove loads by
turning off appliances, press the switch on the
control to OFF and back to AUTO to allow auto­matic remote restarting.

3-7

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3-8

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Restarting The Genset

If the genset shuts down because it is over­loaded, disconnect or turn off as many loads
(appliances) as possible and try to restart the
genset as instructed in Starting and Stopping in
this section. Reconnect the loads one by one up
to 80% of the genset rating.

Resetting Circuit Breakers

If a circuit breaker in the main power distribution
panel or on the genset (see Figure 3-1) trips,
there is either a short circuit or too many loads
operating at the same time. Note that the genset
continues to run after a circuit breaker trips.

If a circuit breaker trips, disconnect or turn off as
many loads (appliances) as possible and reset
the circuit breaker. If the circuit breaker trips right
away, either the main distribution system has a
short or the circuit breaker is faulty.

If the circuit breaker does not trip, reconnect the
loads, one by one, up to 80% of the genset rating.
If a circuit breaker trips right away when a load is
connected, the load probably has a short.

Connecting The System To Utility Power

An approved device such as an automatic trans­fer switch must be provided to keep the genset
and utility from being interconnected. The auto­matic transfer switch automatically reconnects
the utility when service is restored.

Interconnecting the genset and the
public utility (or any other power source) can
lead to the electrocution of utility workers and
damage to equipment and fire. An approved
switching device must be used to prevent
interconnections.

VARYING OPERATING CONDITIONS

Cold Weather

Perform maintenance due according to Periodic
Maintenance in Section 4. See Engine Oil
Recommendations in this section.

An optional thermostatically controlled heater for
the battery is recommended for more reliable
starting in ambient temperatures down to -0° F
(-17.6°C). Genset may crank longer before starting
compared to warmer conditions. This is normal.

Hot Weather

Perform maintenance according to Table 4–1 of
Periodic Maintenance. Make sure nothing blocks
airflow to and from the genset. Keep the cooling
fins clean.

High Altitude

See Powering Equipment in this section for infor-
mation on how altitude affects the maximum
power output of the genset.

Dusty Conditions

Keep the cooling fins clean. Perform air cleaner
maintenance and change engine oil and oil filter
more often than usual. See Periodic Maintenance
in Section 4.

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3-9

GENSET BREAK-IN

Proper engine break-in on a new genset or on
one with a rebuilt engine is essential for top
engine performance and acceptable oil consump­tion. For proper break-in, run the genset at 1/2
rated power for the first 2 hours and then at 3/4
rated power for 2 more hours. Avoid light load or
no load operation during break in. See Powering
Equipment in this section.

Proper engine oil and oil level are especially criti­cal during break-in because of the higher engine
temperatures that can be expected. See Engine
Oil Recommendations in this section. Check the
oil level twice a day or every 4 hours during the
first 24 hours of operation and change the oil after
the first 25 hours of operation.

GENSET EXERCISE

If genset use is infrequent, it is recommended that
the genset be exercised at least 1/2 hour, once a
month, without load. Exercising the genset drives
off moisture, re-lubricates the engine, and
removes oxide from electrical contacts and gener­ator slip rings, thereby promoting better starting,
more reliable operation, and longer engine life.

An operator can exercise the genset by placing
the control switch in the ON position. The genset
would start and run at no load for a time deter­mined by the operator. When the exercise period
is finished, return the control switch to the AUTO
position.

Failure to push the control switch
to AUTO before leaving the genset renders the
genset unavailable for automatic standby
service.

When a transfer switch with an exerciser clock is
available, set the clock to exercise the genset
once a month for 1/2 hour at no load.

See the transfer switch operator’s manual for
instructions on how to adjust and activate the
genset exerciser clock.

GENSET STORAGE

If the genset is to be stored for 120 days or
longer, proper storage is essential for preserving
top genset performance and reliability.

Storing the Genset

1. Push the genset line circuit breaker OFF

(Figure 3-1).

2. Remove the air filter and start the genset.
While the genset is running, spray an engine
fogger (OnaGard

TM

)1into the carburetor, fol­lowing the instructions on the container label,
and then stop the genset. (A fogger coats the
intake, cylinder and exhaust systems with a
protective coat of oil.)

3. Change the engine oil and oil filter. Also,
change the air filter if it is dirty.

4. Disconnect the battery cables (negative [–]
cable first) from the starting battery and store
the battery according to the battery manufac­turer’s recommendations.

5. Close the fuel supply valve. If the genset is
being removed from the premises, cap or plug
any unused fuel line to prevent gas leakage if
a fuel shutoff valve is opened inadvertently.

Leaks can lead to explosive accu­mulations of gas. Natural gas rises when
released and can accumulate under hoods
and inside housings and buildings. LP vapor
sinks when released and can accumulate
inside housings and basements and other
below-grade spaces. Prevent leaks and the
accumulation of gas.

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CAUTION

!

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Returning The Genset To Service

1. Reconnect the starting battery (negative [–]

cable last). See Battery Care in Section 4.

2. Open the fuel supply valve.

3. Inspect the genset. See General Inspection.

4. Start the genset at the genset control panel.
The initial startup may be slow and there may
be smoke and rough operation for a few min­utes until the oil in the cylinders from the fogger

burns off. If the engine does not start, clean
or replace the spark plugs as they may have
been fouled by the fogger.

5. Push the genset line circuit breaker to Run
(Figure 3–1) and the control switch to Auto
for remote, automatic starting and stopping
(transfer switch).

Failure to push the control
switch to AUTO before leaving the genset
renders the genset unavailable for auto­matic standby service.

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4-1

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Automatic startup of the genset
while performing maintenance or service can
cause severe personal injury or death. Push
the control switch to Off and disconnect the
negative (–) battery cable from the battery to
keep the genset from starting while working
on it.

Periodic maintenance is essential for top per­formance and long genset life. Use Table 4-1 as a
guide for normal periodic maintenance. Under hot
or dusty operating conditions some maintenance

operations should be performed more frequently,
as indicated by the footnotes in the table. Keep a
log of maintenance performed and the hours run.
Recording maintenance helps you keep it regular
and provide a basis for supporting warranty
claims.

Maintenance, replacement, or repair of emission
control devices and systems may be performed by
any engine repair establishment or individual.
However, warranty work must be completed by an
authorized Cummins/Onan dealer or distributor.

4. Periodic Maintenance

Refer to Your Honda Owners Manual for Maintenance
Schedule

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WARNING

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* Emission-related items.
(*) Replace the paper element type only.
(1) Service more frequently when used in dusty areas.
(2) These items should be serviced by your service dealer, unless you have the proper tools and are

mechanically proficient. Refer to Honda shop manual for service procedures.

4-2

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GENERAL INSPECTION

Inspect the genset according to the genset
Periodic Maintenance Schedule.

Oil Level

Check the engine oil level as explained under
Checking Engine Oil Level in this section.

Exhaust System

Look and listen for exhaust system leaks while
the genset is running. Shut down the genset if a
leak is found and have it repaired before operat­ing the genset.

Fuel System

Check the fuel supply line and fittings for leaks
while the genset is running. Check flexible fuel
hose sections for cuts, cracks, and abrasions.
Make sure the fuel line is not rubbing against
other parts. Replace worn or damaged fuel line
parts before leaks occur.

Gaseous fuels are highly flamma­ble and explosive and can cause severe per­sonal injury or death. Shut down and repair
leaks immediately.

Battery Connections

Check the battery terminals for clean, tight con­nections. Loose or corroded connections have
high electrical resistance which makes starting

harder. Shut the genset off and disconnect cor­roded or loose battery cables (negative [–] cable
first) and clean and reconnect them as instructed
under Battery Care in this section.

Batteries give off explosive gases
that can cause severe personal injury. Do not
smoke near batteries. Keep flames, sparks,
pilot lights, electrical arcs and arc-producing
equipment and all other ignition sources well
away.

Do not disconnect the battery charger or bat­tery cables while the genset is cranking or
running: the arcing can ignite the explosive
battery gases.

Mechanical

Look for mechanical damage. Start the genset
and look, listen, and feel for any unusual noises
and vibrations.

Check to see that the genset air inlet and outlet
openings are not blocked or clogged with debris.

Clean accumulated dust and dirt from the genset.
Do not clean the genset while it is running or still
hot. Always wear safety glasses when using com­pressed air.

Always wear safety glasses when
using compressed air to avoid severe eye
injury.

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CHECKING ENGINE OIL LEVEL

Set the genset control to the Off position before
checking the engine oil level.

1. Remove the dipstick (see Figure 4-1), wipe it
clean, screw the cap back on and then
remove it again to check the oil level on the
dipstick.

Crankcase pressure can blow
hot engine oil out the fill opening causing
severe burns. Always stop the genset
before removing the oil fill cap or dipstick.

2. Add oil as necessary until the full mark is
reached. See Engine Oil Recommendations
in Section 3. Do Not Fill to a Level Above
the Full Mark on the Dipstick. Drain the
excess oil if too much has been added.
It is not necessary to add oil between oil
changes, if oil level is between upper and
lower limits.

Too much oil can cause high
oil consumption, high operating tempera­tures and oil foaming. Too little oil can
cause severe engine damage. Keep the oil
level between the Full and Add marks on
the dipstick.

3. Secure the oil fill cap by turning clockwise
until secure.

Return the genset control to Auto when finished
performing maintenance.

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WARNING

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CAUTION

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FIGURE 4–1. OIL LEVEL CHECK

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CHANGING ENGINE OIL AND OIL FILTER

Refer to Table 4-1 for scheduled engine oil
change. In hot weather and dusty conditions the
oil should be changed more often.

Set the genset control to the Off position before
changing engine oil.

State and federal agencies have
determined that contact with used engine oil
can cause cancer or reproductive toxicity.
Take care to limit skin contact and breathing
of vapors as much as possible. Use rubber
gloves and wash exposed skin.

1. Place a pan under the oil drain hose. Run the
engine until it is warm and then shut it off.

2. Remove the oil fill cap (see Figure 4-2),
remove the hose plug, open the oil drain
valve (see Figure 3-2), and allow all of the oil
to drain from the engine.

3. Close the oil drain valve and replace the
hose plug.

4. Spin off the oil filter canister (see Figure 3-2)
and catch the oil in the canister. Discard the
oil filter according to local regulations.

5. Thoroughly wipe off the filter mounting sur­face. Make sure that the mounting surface is
clean and free of filter particles (gasket from
old filter is not stuck to surface).

6. Make sure the gasket is in place on the new
filter canister and apply a thin film of oil to the
gasket.

7. Spin on the new filter canister by hand until
the gasket just touches the mounting pad
and then turn it an additional 1/2 to 3/4 turn.
Do not over-tighten.

8. Refill with oil (see Engine Oil Recommenda-
tions in Section 3 and Specifications in Sec­tion 2) for oil capacity. Check oil level.

9. Secure the oil fill cap by turning clockwise
until secure.

10. Used oil is harmful to the environment if it is
not disposed of properly. Pour used oil into a
sealed container and deliver it to the nearest
recycling center or automotive service station.

Return the genset control to Auto when finished
performing maintenance.

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WARNING

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FIGURE 4-2. OIL FILL LOCATION

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AIR FILTER

Refer to Table 4-1 for scheduled air filter replace­ment. In dusty conditions the air filter element and
wrapper should be inspected and changed more
frequently for best operation.

Set the genset control to the Off position before
checking the air filter.

To change the air filter element and wrapper,
loosen the 4 clips and remove the cover (Figure
4-3). Reassemble the air filter with a new air filter
element foam filter element. Do not oil either the

paper or the foam filter elements.

Return the genset control to Auto when finished
performing maintenance.

FIGURE 4-3. AIR FILTER ELEMENTS

4-6

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SPARK PLUGS

Set the genset control to the Off position before
checking the spark plugs.

See Table 4-1 for scheduled spark plug replace­ment. (The genset has two spark plugs: one on
each side of the engine, see Figure 4-3.) The
spark plugs must be in good condition for proper
engine starting and performance. A spark plug
that fouls frequently or has heavy soot deposits
indicates the need for engine service. See
Troubleshooting in Section 11.

To prevent crossthreading a spark plug, always
thread it in by hand until it seats. If the spark plug
is being reused, turn it with a wrench an addition­al 1/4 turn. If the spark plug is new, turn it an addi­tional 3/8 to 1/2 turn. If you have a torque wrench,
tighten the spark plug to 8 lb-ft (10 N-m).

Return the genset control to Auto when finished
performing maintenance.

FIGURE 4–3. SPARK PLUGS

4-7

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BATTERY CARE

See Table 4–1 for scheduled battery maintenance
and to the battery manufacturer’s recommenda­tions and instructions for battery care.

Set the genset control to the Off position before
checking the battery.

Batteries give off explosive gases
that can cause severe personal injury. Do not
smoke near batteries. Keep flames, sparks,
pilot lights, electrical arcs and arc–producing
equipment and all other ignition sources well
away.

Do not disconnect the battery charger or bat­tery cables while the genset is cranking or
running: the arcing can ignite the explosive
battery gases.

Battery electrolyte can cause
severe eye damage and skin burns. Wear gog­gles, rubber gloves and a protective apron
when working with batteries.

Maintain the battery as follows unless the battery
manufacturer has other instructions and recom­mendations:

1. Keep the battery case clean and dry.

2. Make certain that the battery cable connec­tions are clean and tight. Use a terminal
puller tool to remove the battery cables.

3. Identify the cable as positive (+) or negative
(–) before making the battery connections.
Always remove the negative (–) cable first and
connect it last, to reduce the risk of arcing.

4. To remove corrosion from the battery termi­nals, wash the terminals with an ammonia
solution or a solution consisting of 1/4 pound
(about 100 grams) of baking soda in 1 quart
(about 1 liter) of water. Be sure the vent plugs

are tight to prevent cleaning solution from
entering the cells. After cleaning, flush the
outside of the battery and the surrounding
areas with clean water.

5. If the battery is not of the “maintenance-free”
type, maintain the electrolyte level by adding
distilled water. Fill each cell to the split-level
marker in the battery. The water component
of the electrolyte evaporates, but the sulfuric
acid component remains. For this reason,
add water, not electrolyte to the battery.

6. Use a battery hydrometer to check the spe­cific gravity of the electrolyte in each battery
cell (see Figure 4–4). Charge the battery if
the specific gravity measures less than

1.215. Do not overcharge the battery. Stop
charging the battery when the electrolyte
specific gravity reaches 1.260, at approxi­mately 80

° F (27° C).

Return the genset control to Auto when finished
performing maintenance.

FIGURE 4-4. BATTERY CHECK WITH

HYDROMETER

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5-1

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SAFETY

There are hazards in servicing gensets. Study
Safety Precautions and become familiar with the
hazards listed in Table 5–1. Note the following
safeguards and ways of avoiding hazards:

• Reduce the hazard: A safe, orderly workshop

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

• Develop safe work habits: Unsafe proce-

dures lead to accidents when using tools and
machines. Be familiar with the equipment
and its safe use. Use the correct tool for the

job and check its condition before using it.
Observe the warnings in this manual. Take
special precautions when working around
electrical equipment. Do not work alone, if
possible. Do not take risks.

• Use personal protection: Wear appropriate

protective safety equipment, such as safety
shoes and safety glasses. Do not wear rings
or jewelry and do not wear loose or damp
clothing that might get caught in equipment
or conduct electricity.

• Be prepared for an accident: Keep fire extin-

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

5. Preparations for Service

TABLE 5–1. HAZARDS AND THEIR SOURCES

• Leaking fuel

Fire and Explosion

• Hydrogen gas from battery

• Oily rags improperly stored

• Flammable liquids improperly stored

• Hot exhaust pipes

Burns

• Hot engine and generator surfaces

• Electrical shorts

• Jewelry touching electrical components

Poisonous Gas • Operating genset where exhaust gases can accumulate

• Improper generator connections

Electrical Shock

• Faulty wiring

• Working in damp conditions

• Jewelry touching electrical components

Rotating Machinery • Fan and pulley guards not in place

Slippery Surfaces • Leaking or spilled oil

Heavy Objects • Mounting or removing genset

5-2

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SPECIAL TOOLS

The following tools are necessary for servicing
the genset:

Engine Tools

Torque wrench: 0-75 lb-ft (0-100 N-m)

Hole gauge: 0.300-0.400 inch (5-10 mm)

Outside micrometer set: 0-4 inch (0-100 mm)

Telescoping gauge set: up to 4 inch (100 mm)

Feeler gauge

Plasti–Gage bearing clearance guide

Spark plug gap gauge

Oil pressure gauge: 0–30 psi (0–200 kPa)

Manometer: 14 inch (350 mm) WC

Inclined Manometer: 1 inch (25 mm) WC range
with 0.01 inch (0.1 mm) WC divisions

Cylinder compression tester

Flywheel puller

Crankshaft gear puller ring, bolts and puller
(or special shoulder bolts and flywheel puller)

Snap ring pliers

Combination main and cam bearing remover

Oil seal loader and driver

Cylinder ridge reamer

Piston ring spreader

Piston groove cleaner

Piston ring compressor

Cylinder hone

Valve spring compressor

Valve lock replacer

Valve seat cutter kit

Valve guide driver

Slide hammer

Lead or dead–blow hammer

Generator and Control Tools

Rotor removal tool (headless bolt)
(approximately 13 3/8 inches long)

Commutator stone

Battery hydrometer

Digital multi–meter

Load test panel and leads

5-3

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REMOVING AND INSTALLING THE

HOUSING PANELS

Before removing housing panels (Figure 5–1) to
access the genset for maintenance or service,
perform the following steps.

Gaseous fuels are flammable and
explosive and can cause severe personal
injury or death. Do not smoke if you smell gas
or are near fuel tanks or fuel–burning equip­ment or are in an area sharing ventilation with
such equipment. Keep flames, sparks, pilot
lights, electrical switches and arc–producing
equipment and all other sources of ignition
well away. Keep a type ABC fire extinguisher
handy.

NFPA Standard No. 58 requires all persons
handling and operating gaseous fuel to be
trained in proper handling and operating pro­cedures.

1. Close the fuel supply shut off valve. If the
genset can be started, purge the fuel supply
line and genset as much as possible by run­ning the genset until it runs out of fuel with
the shut off valve closed.

2. Press the control switch to Stop.

3. Remove the front access panel (Figure 5–1).

This unit can start automati­cally. Accidental starting of the generator
set while working on it can cause severe
personal injury or death. Prevent acciden­tal starting by disconnecting the negative
(–) cable from the battery terminal.

4. Disconnect the negative (–) battery cable

from the battery to prevent accidental starting.

Do not operate the genset without
the housing panels secured in place. The pan­els guard against rotating parts and bare live
electrical parts that can cause severe person­al injury or death. The housing is also
required for proper genset cooling.

The housing consists of removable side doors
and panels. The two side doors are secured by
latches and the remaining panels are secured by
screws.

To open the side doors, lift handle up and out,
then turn counter-clockwise, swing the side door
down, and lift out.

Disassemble the housing in the following order

5. Remove the side doors.

6. Remove the roof panel by removing the fol­lowing screws.
a. Two screws securing the top face of the
roof to the engine divider panel.
b. Seven screws securing the roof to the
front panel. Note that one of these screws

has a toothed washer to provide a ground
path between the roof and the front panel.

c. Seven screws securing the roof to the
rear panel.

7. Remove the front panel, by removing the
seven screws securing it to the base. Note

that one of these screws has a toothed
washer to provide a ground path between
the front panel and the base.

8. Remove the rear panel as follows.
a. Working inside the unit, remove the two
screws and the panel hole cover (see
Figure 5-1), that is attached to the divider
panel (located directly below the exhaust
pipe) This must be removed to allow the
exhaust pipe to clear the panel during
removal.
b. Inside the unit, remove the two screws
located at the base of the divider panel (see
Figure 5-1).
c. Remove the seven external screws
securing the rear panel to the base. Note

that one of these external screws has a
toothed washer to provide a ground path
between the front panel and the base.

Reassembly is the reverse of disassembly. To
make sure that all of the panel screw holes will
line up, wait to tighten the screws until all of the
panels and screws are in place. Before fitting the
roof panel, it is helpful to screw two M6 studs into
the tapped holes on the top edge of the engine
divider panel. These studs should then be guided
through the holes in the roof panel as it is being
fitted. This will ensure that, once the studs are
removed, the tapped holes in the engine divider
panel are aligned with the holes in the roof panel,
so that the screws can be easily fitted. Pay par­ticular attention to the refitting of the toothed
washers in steps 8,7 and 6, as these are neces­sary to meet the grounding requirements of UL

2200.

Lock the unit to prevent unauthorized access.

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WARNING

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5-4

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PANEL

HOLE

COVER

ROOF

PANEL

FRONT
PANEL

AIR INTAKE

SCREEN

ENGINE DIVIDER

PANEL MOUNTING

SCREWS

ACCESS

DOOR

REAR
PANEL

ACCESS

DOOR

ALTERNATOR

DIVIDER PANEL

MOUNTING

SCREWS

FRONT

ACCESS

PANEL

FIGURE 5–1. GENSET HOUSING

5-5

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ACCESSING THE ENGINE FOR SERVICE

In order to gain access to the engine to carry out
adjustments and/or component replacements,
proceed as follows.

Accidental starting of the genera­tor set while working on it can cause severe
personal injury or death. Prevent accidental
starting by disconnecting the starting battery
cables (negative [-] first).

Ventilate battery area before disconnecting or
connecting batteries. Arcing can ignite the
explosive hydrogen gas given off by batteries,
causing severe personal injury. Arcing can
occur if the negative (-) battery is connected
and a tool is being used to connect or discon­nect the positive (+) battery cable accidentally
touches the frame or other grounded metal
part of the set. To prevent arcing, always
remove the negative (-) cable first, and recon­nect it last.

1. Run the unit out of fuel as described in steps

1 & 2 of Section 5-3

2 Disconnect both battery cables (Battery nega-

tive (B-) first) and remove the battery.

3. Remove the side doors, if not already

removed.

4. Remove the roof panel, as described in step 6

of Section 5-3.

5. Remove the front panel, as described in step
7 of Section 5-3.

6. Remove the battery tray.

7. Remove the bolts securing the gas inlet con­nection to the base.

8. Remove the two bolts that secure the engine
divider panel to the base. Note that one of

these bolts has a toothed washer to provide
a ground path between the engine divider
panel and the base.

9. Carefully swing the engine divider panel,
complete with the fuel inlet connection and
piping, round to the right and lean it against
the engine.

10. This will provide access to the flywheel end of
the engine and the magnetic pick up, for
adjustment and replacement as detailed
elsewhere in this manual.

On completion of the engine work refit the panels
and other components in the reverse order. Do
not tighten the bolts securing the gas inlet con­nection to the base, until the screws securing the
roof panel and the engine divider panel are tight­ened.

Pay particular attention to the refitting of the
toothed washers in step 8 in this section, and in
steps 7 & 6 in Section 5-3, as this is necessary to
meet the grounding requirements of UL 2200.

FIGURE 5-2. ENGINE/GENERATOR ASSEMBLY

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WARNING

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5-6

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THIS PAGE LEFT INTENTIONALLY BLANK

6-1

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by any means, is strictly prohibited.

6. Engine Subsystems

These engine subsystems or service procedures
do not require removal of the cylinder heads,
gearcase or main bearings for access and may
be serviceable without removing the engine from
the cabinet.

CYLINDER COMPRESSION TEST

Examining the spark plugs and testing cylinder
compression can tell much about the condition of
the valves, piston rings and cylinders. Test cylin­der compression as follows:

1. Start the genset and let it warm up.

2. Stop the genset and remove and inspect the
spark plugs. See Ignition System in this sec­tion.

3. Insert the compression gauge nozzle into
one of the spark plug holes, hold the throttle
open and crank the engine. Note the pres­sure indicated by the gauge.

4. Repeat the test on the other cylinder.

5. Compare the readings obtained with the
Cylinder Compression Pressure
Specifications given on Page 2-1.

Note: Do not operate the starter for more
than 5 seconds at one try. If stable compres­sion is not obtained within 5 seconds, stop
the starter motor and wait 10 - 20 seconds to
allow the starter motor to cool, and repeat
the operation again.

6-2

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VALVE CLEARANCE (LASH) ADJUSTMENT

For Specifications, refer to Page 2-1

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

Accidental starting of the generator
set while working on it can cause severe personal
injury or death. Prevent accidental starting by dis­connecting the starting battery cables (negative
[-] first).

The generator will be inoperable dur­ing this inspection and adjustment. Be sure to
notify all potentially affected persons before
beginning work

To access the flywheel and the timing marks on the fan
cover, it is necessary to remove the 2 access doors,
the roof panel, the rear panel and move the engine
divider panel as described on page 5-5.

Inspection & Adjustment

1. Remove the Head Cover Bolt and the Cylinder

Head Cover from both Cylinder Heads.

2. Rotate the flywheel until the “T” mark on the

cooling fan aligns with the “T” mark on the right
side of the fan cover. (This alignment point is Top
Dead Center of No. 1 cylinder, See Figure 6-1.)

Be sure that No.1 cylinder is at TDC on the

compression stroke. This can be checked by “rocking”
the flywheel an inch or so either side of the “T” mark
and observing that both the valves remain closed. If
either valve moves, the engine is at TDC on the
exhaust stroke and must be rotated one complete rev­olution to reach TDC on the compression stroke.

3. Check the intake and exhaust valve clearances for
No.1 cylinder by inserting a feeler gauge between
the valve stem and the valve rocker arm.

4. If the clearance of either valve does not fall within
the specification given in Table 2-1, loosen the
pivot adjusting nut and turn the rocker arm pivot
to obtain the correct clearance.

5. Hold the rocker arm pivot using a wrench, and
tighten the pivot adjusting nut to a torque of 6.5
lbf.ft (9Nm) (Figure 6-2)

6. Recheck the valve clearance after tightening the
adjusting nut.

7. Rotate the flywheel 270

0

in a clockwise direction
until the “T” mark on the cooling fan aligns with
the “T” mark on the left hand side of the fan cover.

8. This will put No.2 cylinder at TDC of its compres­sion stroke.

9. Repeat steps 3,4,5 and 6 for No. 2 cylinder.

10. Replace the cylinder head covers and tighten the
head cover bolts.

11. Refit the engine divider panel, the rear panel and
the roof panel as described in 5-5.

▲

WARNING

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▲

WARNING

!

FIGURE 6-1 FIGURE 6-2

6-3

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EXHAUST SYSTEM

See Figure 6–3. The exhaust system is a welded
assembly that consists of two exhaust manifolds,
muffler, and exhaust pipe. This welded assembly
is mounted inside the heat shield assembly.

Always service a leaking exhaust system before
running a genset. Never try welding a broken or
leaky tailpipe, muffler or manifold.

Exhaust gas is deadly. The
exhaust system must not leak and must dis­charge all engine exhaust away from people,
buildings and areas where exhaust can accu­mulate.

Liability for injury, death, damage and warran­ty expense due to the use of an unapproved
muffler or due to modifications becomes the
responsibility of the person installing the
unapproved muffler or performing the modifi­cations. Use Onan approved exhaust system
parts.

▲

WARNING

!

FIGURE 6-3. EXHAUST SYSTEM

6-4

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Spark Plugs

The genset has two spark plugs. The spark
plugs must be in good condition and have the
proper gap for top engine performance. See

Specifications.

To prevent crossthreading a spark plug, always
thread it in by hand until it seats. Then tighten the
spark plug according to Thread Torques (Page 2-2).
Alternatively, if the spark plug is being reused,
turn it with a wrench an additional 1/4 turn. If the
spark plug is new, turn it an additional 3/8 to 1/2
turn.

If the engine misses or performance otherwise
deteriorates, remove and examine the spark
plugs for signs of the following problems:

Light tan, gray or reddish deposits - Normal

One spark plug fouled - Broken spark plug

cable, low cylinder compression

Soot fouled - Wrong spark plug heat range (too
cold), duty cycle too short for engine to reach nor­mal operating temperature

Fuel fouled - Wrong spark plug heat range (too
cold), faulty choke operation, overly rich fuel mix­ture, dirty air filter

Oil fouled - Malfunctioning crankcase breather,
worn rings, worn valve guides or seals

Burned or overheated - Leaking intake manifold
gaskets, lean fuel mixture

Worn - Spark plug service life used up.

Quick Ignition Test

If the engine misfires, test the ignition system as
follows to quickly determine if the problem is in
the ignition system. First recheck the spark plug
cable connection to each spark plug.

.

Gaseous fuels are flammable and
explosive and can cause severe personal
injury or death. Conduct this test only in a well
ventilated area and make sure you cannot
smell gas. Keep a Type ABC fire extinguisher
handy.

1. Open both access doors and wait several
minutes and make sure you cannot smell gas
before conducting this test.

2. Remove one of the spark plugs.

3. Reconnect the spark plug cable and lay the
spark plug on bare engine metal to ground it.

HIGH VOLTAGE. To prevent
electric shock do not touch the spark plug
or wire during this test.

4. Crank the engine and observe the spark. A
strong, consistent spark indicates that the igni­tion system probably is functioning properly
and the problem is elsewhere. If no spark
occurs or is weak or inconsistent, go to step 5.

5. Repeat step 4 using a new, or known good
spark plug. If still no spark occurs, refer to the
Honda Workshop Manual or your service
dealer.

▲

WARNING

!

▲

WARNING

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6-5

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MAGNETIC PICK UP

The magnetic pick-up is situated directly below the
engine flywheel and is mounted on a bracket that is
secured with the engine mounting bolts at the flywheel
end.

There is an aperture in the plastic fan cover which
allows the tip of the magnetic pick up to be positioned
in close proximity to the starter ring gear on the engine
flywheel.

The red and black leads from the magnetic pick-up are
terminated with “faston” connectors which are con­nected, respectively, to the blue (MAG PU+) and green
(MAG PU -) leads on the Governor Controller Board
situated at the top right corner of the engine divider
panel.

The operation of the magnetic pick-up can be checked
by disconnecting the leads and checking for AC volt­age while cranking the engine. The voltage at cranking
speed should be approximately 5 VAC. Reconnect the
leads after checking.

The voltage at running speed (with the leads connect­ed) should be approx. 22 VAC.

To access the magnetic pick-up, it is necessary to
remove the roof panel, the rear panel and move the
engine divider panel as described in Section 5-5.

The generator will be inoperable dur­ing this adjustment.. Be sure to notify all poten­tially affected persons before beginning work.

Incorrect installation, service, or
replacement of parts can result in severe person­al injury or death, and/or equipment damage.
Service personnel must be trained and qualified
to perform electrical and mechanical work.

Magnetic Pick-up Adjustment

1. Remove the Air Filter Assembly and the Fan Cover.

2. Turn the flywheel until the crown of one of the teeth

on the flywheel ring gear is exactly opposite the
tip of the magnetic pick up.

3. Slide a 0.012 inch feeler gauge between the crown
of the tooth and tip of the magnetic pick up.

4. If necessary, adjust by loosening the locknut and
rotating the magnetic pick-up until the correct
clearance is obtained.

5. Retighten the lock nut and re-check the clearance.

6. Rotate engine one revolution by hand to make sure
ring gear does not hit magnetic pick-up.

7. Refit the Fan Cover and the Air Filter Assembly.

8. Refit the engine divider panel, the rear panel and the
roof panel as described in 5-5

Removal and replacement of the

magnetic pickup

9. Disconnect the magnetic pick-up leads from the
governor controller board leads..

10. Cut the cable ties and remove the leads from the
split conduit.

11. Loosen and remove the bolts which secure the fly­wheel end of the engine and the magnetic pick up
bracket to the engine bracket.

12. Remove the magnetic pick-up bracket with the
magnetic pick-up threaded into it.

13. The magnetic pick-up bracket is not reversible, so
note that the top side is the side through which
the tip of the pick up is protruding. Mark it as such
if necessary.

14. Loosen the lock nut, and unscrew the pick up from
the bracket.

15. Screw a new magnetic pick–up into the bracket, so
that the tip of the pick up protrudes about 1/2 inch
to 5/8 inch (about 13 to 15 mm) on the side
marked top.

16. Fit the magnetic pick-up and bracket to the engine
bracket, and refit the engine mounting bolts.

17. Make sure that the tip of the pick-up is positioned
directly below the center line of the crankshaft,
before tightening the engine mounting bolts.

18. Adjust the pick-up as described in steps 2) through

5) under “Magnetic Pick-up Adjustment” in this
section.

19. Refit the Fan Cover and the Air Filter Assembly.

20. Refit the engine divider panel, the rear panel and
the roof panel as described in Section 5-5.

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WARNING

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6-6

GOVERNOR ROD AND ACTUATOR

See Figure 6–10. The genset controller operates the
throttle by means of the governor rod and actuator
to maintain a nearly constant engine speed (fre­quency) as the electrical load on the genset varies.

To determine if the governor actuator is defective
or needs to be replaced, check the coil resistance

with the two leads disconnected. Coil resistance
should be 1.5 to 3.0 ohms and open to ground.
Also, with the leads disconnected, apply 12 VDC
to the actuator. The actuator should open the car­buretor to full throttle.

If necessary, replace the governor actuator per
governor actuator setting procedure located at
section 6-5.

FIGURE 6–10. GOVERNOR ROD AND ACTUATOR

For Index of Components See Figure 6-11.

6-7

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GOVERNOR ADJUSTMENT

The relationship between the Governor Actuator and
the Carburetor has been carefully set during assembly,
to give the required performance and should not
require adjustment.

If either the Actuator or the Carburetor is replaced,
then the settings should be checked and adjusted as
follows.

1. To access the Carburetor and Governor Rod
a. Remove the roof panel (Section 5-3).
b. Remove the Air Cleaner assembly (Section
4-5).

2. To adjust the Carburetor
a. Holding the butterfly closed by hand, adjust

the Idle Stop Screw (Figure 6-11 Item 23) until
a 0.006” (0.15mm) feeler gauge is a snug fit
between the Idle Stop Screw and the
Carburetor Throttle Lever (Figure 6-11 Item 8).

b. Remove the feeler and turn the Idle Stop

Screw a further one and one quarter turns
(1 1/4) clockwise.

3. To adjust the Actuator
a. Check that the carburetor is correctly adjusted

as above.

b. Check that the distance from the actuator

housing to the shoulder at the end of the
ground portion of the actuator shaft (Section
6-11 Item 24) is 0.500” (1/2 inch or 12.7mm).

c. If adjustment is required, loosen the clevis

lock nut (Figure 6-11 Item 11).

d. Holding the clevis (Figure 6-11 Item 10) from

turning, rotate the actuator shaft until the
correct dimension is obtained.

e. Tighten the clevis locknut and recheck the

dimension.

f. Move the actuator through its range of motion

by hand, verifying that the linkage is free at
both the idle and full throttle positions.

4. Refit the Air Cleaner (Section 6-8) and the roof
panel (Section 5-3)

FIGURE 6–11

1 BEARING - BALL
2 10-32 x 3/4 FILHMS
3 10 - 32 HEXNUT
4 #10 LOCK WASHER
5 8-32 X 5/16 PHMS
6 8-32 HEXNUT
7 #8 LOCK WASHER
8 LEVER - THROTTLE
9 ROD - ACTUATOR
10 CLEVIS
11 JAM NUT (SUPPLIED WITH ACTUATOR)
12 ACTUATOR
13 M5 X 0.8 X 30 HHCS
14 M5 X 0.8 HEXNUT
15 CLAMP - GOVERNOR
16 M6 X 1.0 HEXNUT
17 BRACKET - THROTTLE
18 M8 LOCK WASHER
19 M8 X 1.25 X 20 HHCS
20 #10-32 NUT W / WASHER
21 M5 X 0.8 HEXNUT
23 IDLE STOP SCREW
24 ACTUATOR SHAFT
25 SLOTTED SHAFT

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FIGURE 6–12. AIR CLEANER

6-8

FUEL SYSTEM

The engine is equipped with a fuel system that is
designed to run on either natural gas or LP vapor.

A genset purchased to use natural gas or LP vapor
can not be converted to use LP liquid.

The genset leaves the factory set up for natural
gas. If the genset uses LP vapor, follow conver­sion instructions in the Installation Manual.

Gaseous fuels are flammable and
explosive and can cause severe personal
injury or death. Do not smoke if you smell gas
or are near fuel tanks or fuel-burning equip­ment or are in an area sharing ventilation with
such equipment. Keep flames, sparks, pilot
lights, electrical switches and arc-producing
equipment and all other sources of ignition
well away. Keep a type ABC fire extinguisher
handy.

NFPA Standard No. 58 requires all persons
handling and operating gaseous fuel to be
trained in proper handling and operating pro­cedures.

Gaseous fuel leaks into an inade­quately ventilated space can lead to explosive

accumulations of gas. Natural gas rises when
released into the air and can accumulate
under overhanging hoods and inside hous­ings and buildings. LPG sinks when released
into the air and can accumulate inside hous­ings, basements and other below–grade
spaces. Precautions must be taken to prevent
gas leaks and the accumulation of gaseous
fuel in the event of a leak.

Air Cleaner Assembly

Disassembly:

1. Open the side access doors. (See Removing
and Installing the Housing Panels in Section 5.

2. Loosen the four spring clips (Figure 6–12).

3. Lift off the air cleaner element assembly.

4. Remove the five screws that secure air
cleaner housing (two screws to the support
bracket and the three screws to the carbure­tor) and remove housing.

Reassembly: Reassembly is the reverse of dis­assembly. Use a new gasket between the adapter
and the carburetor.

Note: When replacing the air cleaner housing,
take care to reattach the crankcase breather hose
to the stub on the bottom face of this housing. A
pair of long needle nose pliers will be helpful for
this.

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WARNING

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6-9

FIGURE 6–13. LP VAPOR/NATURAL GAS FUEL SYSTEM

NG / LP Vapor Fuel System

The fuel system for NG or LP vapor consists of a
3/4” NPT female gas supply connection (located
toward the bottom right hand side of the front
access panel), supplying fuel through a pair of
fuel shut off solenoids (plumbed in series, wired in
parallel) to a gas pressure regulator (located at
the top left hand corner of the engine divider
panel). A vent tube from the regulator protrudes
through the engine divider panel to ensure that
the atmospheric pressure at the regulator and at
the carburetor is balanced.

The gas pressure regulator fitted to the unit pro­vides constant gas pressure to the carburetor
under varying load conditions. It is pre-set and
sealed to comply with EPA and CARB regula­tions.

The change of gas supply between NG and LP
vapor is accommodated simply by fitting the
engine hose to the appropriate outlet on the tee­piece at the regulator (refer to Figure 6-13). No

adjustment to the regulator is necessary or possi­ble.

Adjusting Inlet Gas Supply Pressure:

There is a pressure test port on the inlet side of
the regulator. To access this test port it is neces­sary to remove the roof panel (Section 5-3). The
pressures given in the Specifications (Section 2-

1) are taken at this point, which is after the fuel
shut off solenoids.

A more practical and convenient method of
checking and adjusting the inlet pressure is to
connect a manometer, by means of a suitable tee
piece, between the gas supply and the Fuel Inlet
fitting on the unit (Figure 3-2). The manometer
should have a scale range of at least 14 inches
(350 mm)

The pressure at this point, on either NG or LP
vapor, should be 2 inches (25mm) WC greater
than the pressure given in the Specifications
(Section 2-1) to allow for the pressure drop
through the fuel solenoid valves.

Redistribution or publication of this document,

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6-10

Adjust the supply pressure as follows:

1.Close the gas supply shut off valve.

2. Disconnect the gas supply pipe, and fit a
tee-piece and the manometer.

3. Reconnect the gas supply pipe.

4. Test for leakage by performing a soap

bubble test.

5. Open the gas shut off valve.

6. With the genset at rest, adjust the gas
supply pressure regulator to obtain
between 7 and 13 inches (178-330mm)
WC.

7. Start the unit, and while running at no
load, note the gas supply pressure.

Adjust if necessary.

8. If the genset is operable, check the gas
supply pressure under full load. If gas
pressure drops below the required mini
mum of 7 inches (178mm) WC, the gas
supply piping may be too small. On an
LP vapor supply system, the tank may be

too small to provide the required rate of
vaporization, or it may not contain
enough fuel.

NOTE: Be sure to have all other gas
appliances running during this test, to
place full demand on the gas supply.

9. Close the gas supply shut off valve

10. Disconnect the manometer, and remove
or plug off the tee piece.

11. Open the gas shut off valve

12. Before returning the unit to service, test
for leakage, by performing a soap bubble
test at any connection point that has

been disturbed.

Fuel Solenoid Valve Tests

To access the fuel solenoid valves, remove the

roof panel (Section 5-3)
Replace a leaky fuel solenoid valve or one that
fails to open.

To test for leakage, use a test pressure of at
least 11 inches (279mm) WC and perform a
soap bubble test.

To test for opening, jumper both solenoids
across the battery cable connections at the
genset. A manometer connected to the test port
on the regulator can be used to indicate whether
both valves are opening.

Gaseous fuels are flammable and
explosive and can cause severe personal
injury or death. Do not smoke if you smell gas
or are near fuel tanks or fuel-burning equip­ment or are in an area sharing ventilation with
such equipment. Keep flames, sparks, pilot
lights, electrical switches and arc-producing
equipment and all other sources of ignition
well away. Keep a type ABC fire extinguisher
handy.

NFPA Standard No. 58 requires all persons
handling and operating gaseous fuel to be
trained in proper handling and operating pro­cedures.

Gaseous fuel leaks into an inade­quately ventilated space can lead to explosive
accumulations of gas. Natural gas rises when
released into the air and can accumulate
under overhanging hoods and inside hous­ings and buildings. LPG sinks when released
into the air and can accumulate inside hous­ings, basements and other below–grade
spaces. Precautions must be taken to prevent
gas leaks and the accumulation of gaseous
fuel in the event of a leak.

▲

WARNING

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▲

WARNING

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7-1

7. Generator

GENERAL DESCRIPTION

The YVB generator (Figure 7–1) is a two-pole,
revolving field, brush-type design with drip-proof
construction. It is regulated by the microproces­sor-based genset controller.

The generator rotor and engine crankshaft have a
tapered coupling secured by the rotor through­bolt. The other end of the rotor is supported in a
sealed, pre-lubricated ball bearing assembly. The
cooling blower wheel is bolted to the rotor assem­bly

ROTOR

STATOR

ASSEMBLY

WRAPPER

ASSEMBLY

ROTOR

WINDINGS

COLLECTOR

RING

END

BEARING

GENERATOR

FAN

FAN MOUNTING

DISC

ROTOR

HUB

END BELL ASSEMBLY (SEE FIGURE 8–2

FOR BRUSH CONFIGURATION)

MOUNTING

FOOT

FIGURE 7-1 YVB GENERATOR

Redistribution or publication of this document,

by any means, is strictly prohibited.

7-2

SERVICING BRUSHES AND SLIP RINGS

Remove the rear panel to access the generator
brushes. See Removing and Installing the
Housing Panels in Section 5.

Remove the brush block and inspect for burned
brushes and grooved or pitted slip rings and other
damage. (Turn the rotor to inspect all the way
around the slip rings.)

If everything looks good, check brush wear with a
piece of wire marked off as shown in Figure 8–2.
Replace the brushes and brush springs if the wire
can be inserted more than 1 inch (25 mm) into the
hole in the brush holder. (Make sure the wire rests
on top of the brush and not on part of the brush
spring.)

If the slip rings are grooved or pitted try cleaning
them up with a commutator stone. If the slip rings
need to be replaced, see Removing and Replacing
the Slip Ring Assembly under Generator Assembly/
Disassembly in this section.

To replace the brushes or to clean up the slip rings:

1. Disconnect the leads marked F1 and F2 from

the brush block terminals.

2. Remove the brush block mounting screws (2)
and lift out the brush block assembly.

Incorrect installation, service, or
replacement of parts can result in severe per­sonal injury or death, and/or equipment dam­age. Service personnel must be trained and
qualified to perform electrical and mechanical
work. When carrying out the following proce­dure, be aware of the dangers of working with
rotating parts. Take care to keep body parts,
hair and loose clothing from coming into con­tact with rotating parts.

3. If the slip rings need to be cleaned up, insu-

late the ends of leads F1 and F2, disconnect
all leads from the positive (+) terminal of the
ignition coil to keep the engine from starting,
hold the commutator stone lightly against the
slip rings and crank the engine for 3 to 6 sec­onds. Check the slip rings and repeat the
procedure as necessary until the pits and
groves have been removed. Clean any
resulting debris from the inside of the gener­ator, using compressed air, if available, or a
small brush.

4. Replace the brushes and brush springs with

new parts. Connect each brush pigtail to the
terminal on its side of the insulating divide
(Figure 7–3).

5. Remount the brush block. Center the brush­es on the slip rings before tightening the
mounting screws.

6. Reconnect the lead marked F1 to the out­board brush terminal and the lead marked F2
to the inboard brush terminal and secure.

7. Reassemble Housing as detailed in Section 5.

BRUSH BLOCK

ASSEMBLY

MEASURING

WIRE

GENERATOR

BEARING

1 INCH

BRUSH

SPRING

BRUSH

LEAD

TERMINALS

BRUSH

PIG TAILS

FIGURE 7-2 CHECKING BRUSH WEAR

FIGURE 7-3 BRUSH BLOCK ASSEMBLY

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7-3

GENERATOR DISASSEMBLY/ASSEMBLY

The following sections describe the disassembly
and reassembly procedures for the generator.
Figure 7–4 illustrates generator assembly.

Generator components are heavy
and can cause severe personal injury if
dropped or lifted during service. Be careful,
use appropriate lifting techniques, keep
hands and feet clear during service, and use
the recommended service procedures.

Disassembly

1. Remove the rear panel. See Removing and
Installing the Housing Panels in Section 5.

Check lead markings before disconnecting a
lead. If the lead makings do not clearly identi­fy reconnection, mark the leads with tape.

2. Remove the two harness clamps that secure
the harness to the outside of the generator
(Figure 7–4).

3. Remove the cover from the control box and
disconnect stator leads T1 and T4 from the
circuit breaker and T2 and T3 from the neu­tral terminal. Cut necessary cable ties to
remove these leads from the harness sleev­ing up to the rear of the generator.

4. Disconnect leads Q1 and Q2. Connectors
are located in the harness sleeving at the
rear of the generator (Figure 7–4).

5. Disconnect leads F1 and F2 from the brush
block terminals (Figure 7–3).

6. Remove the bonding strap from the genera­tor mounting foot.

7. Remove the exhaust assembly (see Exhaust
System in Section 6).

▲

WARNING

!

FIGURE 7-4 ALTERNATOR HARNESS

Redistribution or publication of this document,

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7-4

8. To keep from damaging the brushes and to
keep them from interfering when remounting
the stator, either:

A. Remove the brush block assembly by

disconnecting the leads marked F1 and
F2 from the brush block terminals
(Figure 7–3) and then removing the two
mounting screws, or

B. Insert a stiff wire through the small hole

in the end of the stator housing and into
the brush block, to hold the brushes up
and out of the way (Figure 7–5). To do
this, first pull both brush pigtails to lift the
brushes off the slip rings.

9. Remove the two generator vibration isolator
center-bolts.

10. Place a piece of “two-by-four” lumber under
the rear of the engine mounting plate to sup­port the engine.

11. Remove the four nuts(Figure 7-6 item 20)
and lock washers (Item 21) from the genera­tor studs (Item 22). Pry the end bell free of
the rotor bearing. Be careful not to damage
the brush holder. (Figure 7–6).

12. Pull the stator/wrapper assembly off the rotor
and away from the engine, taking care not to
scrape stator windings. Set it aside.

INSERT A RETAINING

WIRE TO KEEP THE

BRUSHES OUT OF THE

WAY WHEN ASSEMBLING

AND DISASSEMBLING

THE GENERATOR

RETAINING

WIRE

FIGURE 7-5 BRUSH BLOCK ASSEMBLY

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by any means, is strictly prohibited.

7-5

FIGURE 7-6 GENERATOR DISASSEMBLY/REASSEMBLY

Redistribution or publication of this document,

by any means, is strictly prohibited.

7-6

Removing the Rotor

1. Remove the rotor through stud. (Use two
nuts locked together at the end of the rotor
through stud to loosen and remove stud from
crankshaft.)

2. Thread in a rotor removal rod (Figure 7–7)
and turn it with a screwdriver until it bottoms
in crankshaft. Thread in and tighten a 9/16­12 x 1-3/4 inch bolt against the rod until the
rotor breaks loose from the crankshaft. A tap
with a lead hammer on the rotor assy. May be
required. Be careful not to hit the windings.

3. If necessary, replace the bearing and the slip
ring assembly as instructed in this subsection.

Remounting the Rotor

Replace the bearing and the slip ring assembly, if
necessary, as instructed in this section. Use the
rotor removal tool to guide the rotor on. Torque
the through bolt to torque indicated in Section 2-2
Thread Torques.

APPROXIMATELY 13 3/8

INCHES LONG

SCREWDRIVER

SLOT

REMOVAL BOLT

FIGURE 7-7 ROTOR REMOVAL TOOL

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7-7

Remounting the Stator Housing

Remounting is the reverse of removal. Note the
following:

1. Mount the rotor.

2. Make sure the brush block assembly has
been removed or that the wire is holding both
brushes up and out of the way.

3. Make sure the bearing O-ring is in place in
the housing bearing bore.

4. Torque the stator housing nuts, the rotor
through stud nut and vibration isolator center
bolts to Thread Torques in Section 2.

5. Make sure to secure the bonding strap to the
generator mounting foot using one EIT
(external and internal toothed) lock washer
on each side of the strap terminal for a good
electrical connection.

6. Reconnect or reassemble all other parts that
were disconnected or removed.

7. Install the brush block assembly if it was
removed. If it was left in place, pull the brush
pig tails and remove the retaining wire. If nec­essary, loosen the brush block mounting
screws, align the brush block so that the
brushes are centered on the slip rings and
retighten the mounting screws.

8. Connect the lead marked F1 to the outboard
brush terminal and the lead marked F2 to the
inboard brush terminal.

9. Replace all cable ties that were removed dur­ing this procedure.

Removing and Replacing the Rotor
Bearing with the Rotor already removed.

Use a gear puller to remove the bearing from the
rotor shaft if it or the slip ring assembly is to be
replaced, otherwise leave it in place. If the bearing
is to be reused, make sure the fingers of the gear
puller bear on the inner race of the bearing only.

The bearing will be damaged and
become unusable if force is applied to the
outer race either when pulling it off or press­ing it on.

Replace the bearing as follows:

1. Replace the slip ring assembly first, if neces­sary.

2. Bearing is glued on. Follow the instructions in
the Bearing Replacement Kit.

Removing and Replacing the Slip Ring
Assembly

Unsolder the two rotor leads from the slip ring
assembly and pull the slip ring assembly off with
a gear puller. Tape the key to the shaft to keep
from loosing it if a new assembly is not going to
be installed right away.

Press on a new slip ring assembly with a press,
making sure the key is in place and the assembly
is aligned with the key. Solder the two rotor leads
to the solder terminals on the slip ring assembly.

▲

CAUTION

!

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by any means, is strictly prohibited.

7-8

TESTING THE GENERATOR

The following tests and adjustments can be per­formed without disassembly of the generator.

Many troubleshooting procedures
present hazards that 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.

Testing Field Flash Voltage

Incorrect installation, service, or
replacement of parts can result in severe
personal injury or death, and/or equipment
damage. Service personnel must be trained
and qualified to perform electrical and
mechanical work. When carrying out the
following procedure, be aware of the dangers
of working with rotating parts. Take care to
keep body parts, hair and loose clothing
from coming into contact with rotating parts.

Field flash voltage can be tested at the brush
holder terminals with a DC voltmeter (Figure 7-8).
With the engine cranking, check for 12 VDC. If
present, check for open windings in the rotor. If
not present, alternator harness or genset control
(A11) PCB is defective.

▲

WARNING

!

BRUSH BLOCK

ASSEMBLY

LEAD (F2

TO A11-F2)

LEAD (F1

TO A11-F1)

TEST POINTS

FIGURE 7-8 FIELD VOLTAGE TEST POINTS

▲

WARNING

!

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by any means, is strictly prohibited.

7-9

Testing the Rotor

The generator circuits can be tested without hav­ing to disassemble the generator. It is recom­mended that an ohmmeter be used to check for
open circuits and an insulation resistance meter
for grounded circuits. An ohmmeter can be used
to check for grounded circuits, but it may not be
able to detect marginal insulation breakdown.

Testing for Grounds: Check for grounds between
each slip ring and the rotor shaft, Figure 7–9. Use
a Megger or insulation resistance meter which
applies 500 VDC at the test leads. Perform test
as follows:

1. Isolate the rotor windings by disconnecting
the two leads to the brush holder.

2. Connect test leads between each ring and
the rotor shaft in turn. Meter should register
100,000 ohms or greater.

3. If less than 100,000 ohms, rotor is question­able. Thoroughly dry the rotor and retest.

4. Replace a grounded rotor with a new identi­cal part.

Testing for Open or Shorted Windings: Perform
this test with an accurate meter such as a digital
ohmmeter.

1. Isolate the rotor windings by disconnecting
the two leads to the brush holder.

2. Using ohmmeter, check resistance between
F1 and F2 collector rings (25.47 ohms

±

10%), Figure 8–10.

If there is a large difference, replace the defective
rotor with new, identical part.

MEGGER OR

INSULATION

RESISTANCE

METER

CONNECT LEADS

BETWEEN EACH RING

AND ROTOR SHAFT

FIGURE 8-9 TESTING ROTOR FOR GROUNDS

CONNECT LEADS

BETWEEN F1, F2

SLIP RINGS

DIGITAL

OHMMETER

FIGURE 7-9 TESTING ROTOR FOR GROUNDS

FIGURE 7-10 TESTING ROTOR FOR AN OPEN

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7-10

Testing Generator Stator

Using proper test equipment, check the stator for
grounds, opens, and shorts in the windings.
Isolate the stator windings by disconnecting all six
stator leads. Test each winding T1-T2, T3-T4, Q1­Q2.

Testing for Grounds: Some generators have
ground connections to the frame. Check wiring dia­gram. All stator leads must be isolated for testing.

Use a megger or insulation resistance meter
which applies not more than 500VDC to the test
leads (Figure 7–11). Test each stator winding for
short to laminations. A reading of less than
100,000 ohms indicates a questionable stator.
Thoroughly dry the stator and retest.
T1,T2,T3,T4,Q1,Q2 : be open to ground.

Testing for Open or Shorted Windings: Test for
continuity between coil leads as shown in Figure
7–12. Use an accurate instrument for this test
such as a Wheatstone Bridge. Resistance should
correspond to the values shown below.

• Resistance values (± 5%):

T1-T2: 0.095 ohms
T3-T4: 0.095 ohms
Q1-Q2: 1.185 ohms
T1-T3: open
T1-T4: open
T2-T3: open
T2-T4: open
T1,T2,T3,T4-Q1: open
T1,T2,T3,T4-Q2: open

If a winding is shorted, open or grounded, replace
the stator assembly. Before replacing the assem­bly, check the leads for broken wires or insulation.

CONNECT LEADS BETWEEN

EACH WINDING AND GROUND

FIGURE 8–11. TESTING STATOR WINDIN G FOR

GROUNDS

CONNECT LEADS

BETWEEN PAIRS

OF STATOR

WINDING LEADS

FIGURE 7-11 TESTING STATOR WINDING FOR

GROUNDS

FIGURE 7-12 TESTING STATOR WINDING

RESISTANCE

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8-1

8. Genset Control PCB (A11)

The genset control PCB (A11) is a fully potted
assembly with one connector (P1) and is mounted
by one screw to the generator control assembly. A
bracket is also used at the top of the control PCB
for additional bracing for removing and installing
the P1 connector. To remove the control PCB,
perform the following steps.

3. Remove the side access doors, top and front
access panel. (See Removing and Installing
the Housing Panels in Section 5 for instruc­tions and important safety precautions.)

4. Remove connector P1 from the control PCB
(Figure 8–1). To remove connector, insert
small blade screwdriver into slot of connector

retainer tab. Move tab downward to release
and remove connector.

5. Remove retainer screw from the base of the
control PCB.

6. Loosen the lower two screws and remove the
upper four screws that secure the control
assembly panel to the engine divider panel.

7. Lightly pull back on the top of the control
assembly until the connector on the back of
the control PCB clears the cutout in the back
of the engine divider panel.

8. With the control assembly tilted back, lift up
on the control PCB to release the bracket
from the control assembly and remove the
control PCB.

SMALL BLADE

SCREWDRIVER

REMOVE

(FOUR SCREWS)

CONNECTOR

P1

ENGINE DIVIDER

PANEL

LOOSEN

(TWO SCREWS)

CONTROL

PCB (A11)

CONTROL

ASSEMBLY

CONTROL PCB

RETAINER

SCREW

RETAINER

TAB SLOT

BRACKET

CUTOUT

FIGURE 8-1 REMOVING CONTROL PCB

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by any means, is strictly prohibited.

8-2

The control PCB uses a microprocessor with
embedded software. The micro–controller supports
the traditional functions of genset control along with

voltage regulation and extensive diagnostics (see
Troubleshooting, Section 11). Figure 8–2 is a block
diagram of control PCB inputs and outputs.

+-

OUTPUT VOLTAGE SENSE

AC POWER OUTPUT

FIELD CURRENT

BRUSHES/

SLIP RINGS

ROTATING

MECHANICAL

POWER INPUT

OF ENGINE

FUEL

IGN

START

MAIN STATOR (G1)

MAIN ROTOR

(FIELD)

RUN-OFF-AUTO SWITCH AND STATUS/DIAGNOSTICS LED

AUTOMATIC TRANSFER SWITCH

ENGINE SENSOR (LOP)

+

-

GENSET

CONTROL

PCB (A11)

Q1/Q2 (FIELD POWER AND FREQUENCY SENSE)

FIGURE 8-2 GENSET CONTROLLER INPUTS AND OUTPUTS

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by any means, is strictly prohibited.

9-1

9. Governor Controller Board (A12)

The genset governor controller board (A12) is
mounted on the engine divider panel, directly
above the control PCB. It receives the governing
control (tachometer) signal from the magnetic
pick-up and B+ from the control PCB.

THIS CONTROLLER IS PROGRAMMED
SPECIFICALLY FOR THE 12GRCA. IN ORDER
TO ENSURE CORRECT OPERATION OF THE
12GRCA UNIT, THIS CONTROL MUST BE
ORDERED FROM AN AUTHORIZED DEALER.

The governor controller board outputs a DC volt­age that drives the governor actuator, which in
turn moves the carburetor throttle to maintain an
engine speed of 3600 RPM (60 Hz). The input
from the magnetic pick-up and B+ from the con­trol PCB can signal the governor controller board
to shut the engine off under the following adverse
conditions:

• If power (B+) is lost to the control PCB

• Any control PCB shutdown fault

• If signal from the magnetic pick-up stops

Under all these circumstances, governor con­troller board shuts down the genset. The governor
controller board is a non-serviceable component.

Note: This controller possesses a warm up fea­ture to assist with low ambient start up. As part of

the warm up sequence, the genset will climb to
2600 rpm and maintain this speed for up to 8 sec­onds. After 8 seconds, the unit will then ramp up
until it reaches its running speed of 3600 rpm.
The total time for the start up sequence to occur
can be as long as 18 seconds.

GOVERNOR CONTROLLER BOARD

TROUBLESHOOTING

When starting the genset, the actuator should
open the carburetor to approximately 1/2 throttle.
If not, first check the operation of the actuator and
linkage (see Governor Rod and Actuator in
Section 6) and also the ignition system (see
Ignition System in Section 6) and then check the
following to determine if the governor controller
board is defective.

The status indicator on the governor controller
board should light for 1 second, then off for 1 sec­ond and then remain on during cranking and
genset operation. If the indicator flashes more
than once, the governor controller board is
defective.

If the indicator does not light, check all connec­tions before replacing the governor controller
board. Also check for +12 VDC at the ignition coil.
If not present the controller PCB may be defective.

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by any means, is strictly prohibited.

9-2

FIGURE 9–1. GOVERNOR CONTROLLER BOARD A12

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by any means, is strictly prohibited.

10-1

10. Troubleshooting

Table 10–1 provides troubleshooting guidance for
a genset that fails to start or that shuts down. The
genset controller has an extensive diagnostic
capability and its fault codes are covered in
numerical sequence in Table 110–1. Gaps in the

code numbers are for codes that do not apply to
this genset.

Most shutdowns can be prevented by proper
maintenance and use of the genset—maintaining
oil levels, keeping battery connections clean and
tight, and not overloading the genset.

STATUS/DIAGNOSTICS LIGHT ON THE

GENSET CONTROL SWITCH

The genset controller causes the status/diagnos­tics LED to indicate a fault code if there is a fault
shutdown that requires maintenance or service.
There are distinct (longer) pauses between repe­titions of the code blink transmissions.

Single-Digit Fault Code – A single-digit fault
code is indicated by a corresponding number of
blinks. For example:

Code No. 4: blink-blink-blink-blink-long pause
repeat code

Two-Digit Fault Code – A two-digit fault code is
indicated by two sets of blinks separated by a
short pause. The first set corresponds to the tens
digit and second to the ones digit. For example:

Code No. 32: blink-blink-blink-pause-blink-blink-
long pause-repeat code

FAULT CODE LEVEL

There are two levels of fault codes. Level One is
a “single digit” fault code that indicates engine
faults (possibly correctable by customer) or that
there is a level two fault.

Level Two fault is a “two digit” fault code that
requires repair by an authorized service repre­sentative.

DISPLAYING LEVEL ONE/TWO FAULT

CODES

Immediately following a fault shutdown, the indi­cator light will blink a Level One fault code and will
stop after five minutes. To restore and read this
fault, perform the following:

9. Disconnect the remote start wire from the ter­minal block of the control assembly (TB1-5).
This will prevent accidental starting of the
genset by the transfer switch while perform­ing this procedure.

10. Grasp the side of the Run/Off/Auto switch
and toggle the switch three times between
Off and Auto within five seconds.

11. The Level One fault code will be displayed. If
a Level One fault code “3” is displayed, a
Level Two fault has occurred. To display the
Level Two code, toggle the switch one more
time between Off and Auto.

12. See Table 10–1 for troubleshooting guidance
of indicated fault code.

Note: The fault displayed is the last fault logged
and will remain in memory even though the condi­tion has been corrected and the genset is running
normally.

Automatic startup of the genset
while performing maintenance or service can
cause severe personal injury or death. Push
the control switch to Off and disconnect the
negative (–) battery cable from the battery to
keep the genset from starting up while work­ing on it.

Hot engine parts can cause severe
burns. Always allow the engine time to cool
before performing any maintenance or service.

▲

WARNING

!

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-2

TABLE 10–1. TROUBLESHOOTING

Some genset service procedures present hazards that can result in severe per­sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

NO RESPONSE WHEN THE CONTROL SWITCH IN THE RUN POSITION

(Marginal batteries, connections, or charging system)

Corrective Action:

1. Replace Fuse F1 (B+) if blown.

2. Clean and tighten the positive (+) and negative (–) battery cable connections at the battery and

genset.

3. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations.

4. Test the battery charging system and service as necessary. See Flywheel Alternator - Section 6.

5. Push the control switch to Auto and try starting the genset through the transfer switch control.
Replace control switch S2 if the genset can be operated remotely but not locally.

6. Resettable fuse on genset control PCB is open. Check for short to ground in the starter, fuel sole­noid, ignition, field flash circuits.

7. Replace the genset control PCB (see Section 8).

NO POWER—GENSET RUNNING, RUN LIGHT ON

(Line circuit breaker OFF or tripped or faulty wiring)

Corrective Action:

1. Turn on or reset the line circuit breaker on the genset.

2. Turn on or reset the line circuit breakers on the main distribution panel.

3. Check for proper transfer switch function.

4. Check genset AC output connections at the equipment (transfer switch) and reconnect as nec­essary.

5. Attempt to reset the circuit breakers and measure electrical continuity across terminals. Replace
a circuit breaker that does not close or that has measurable resistance across the contacts.

6. Check all AC wiring connections in genset.

LOW OIL FAULT—CODE NO. 2

(The controller sensed that the low oil pressure cutoff did not open within 10 seconds of starting or

closed during operation)

Corrective Action:

1. Check engine oil level and add oil as necessary. Repair oil leaks.

2. Drain excess oil. (Excess oil leads to foaming and a consequent loss of oil pressure.)

3. Repair the low oil pressure cutoff switch (S1) wiring or replace defective switch.

4. Service a worn lubricating system and/or engine according to Engine Subsystems (Section 5)
and/or Honda recommendations).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-3

TABLE 10–1. TROUBLESHOOTING (CONT.)

Some genset service procedures present hazards that can result in severe per­sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

SERVICE CHECK FAULT—CODE NO. 3

(A Level Two fault occurred)

Corrective Action: Check the second–level fault code. See Displaying Level One/Two Fault Codes
in this section.

OVERCRANK FAULT—CODE NO. 4

(Cranking exceeded 20 seconds without engine starting)

Corrective Action:

1. Open any closed fuel shutoff valves.

2. Check the governor linkage for binding and service as necessary (see Governor Linkage and
Actuator in Section 6).

3. Check magnetic pick-up for proper operation (See Section 6-5).

4. Fill the LPG fuel tank if less than half full. On cold days the LPG container may have to be kept at
least half full to provide the rate of vaporization required to keep up with genset fuel demand. LPG
with more than 2.5 percent butane will not vaporize below 32

° F (0° C). Use HD-5 grade LPG.

5. Inspect/secure the spark plug cable on the spark plugs.

6. Service the air cleaner.

7. Check for a blocked exhaust system and service as necessary.

8. Check fuel solenoid valve operation (see Fuel System in Section 6).

9. Check the gas supply pressure and adjust as necessary (see Fuel System in Section 6).

10. Conduct the ignition system tests and service as necessary (see Ignition System in Section 6).

11. Check the governor controller board (see Section 9).

12. Conduct a cylinder compression test and service the engine if it is worn or malfunctioning.

OVERVOLTAGE FAULT—CODE NO. 12

(Controller not able to regulate to rated voltage)

Corrective Action:

1. Service the brushes and slip rings as necessary (see Servicing Brushes and Slip Rings in Section 8).

2. Replace the genset control PCB (see Section 8).

UNDERVOLTAGE FAULT—CODE NO. 13

(Controller not able to regulate to rated voltage)

Corrective Action:

1. Turn the genset line circuit breaker OFF. If the genset runs without shutting down, run the genset
with fewer connected loads.

2. Check power factor. Disconnect loads that cause a power factor of 0.5 or less.

3. Service the brushes and slip rings as necessary (see Servicing Brushes and Slip Rings in Section 7).

4. Test the generator field, stator and guadrature windings for opens or shorts. Replace the gener­ator rotor or stator assembly if winding resistance is not as specified in Section 7.

5. Replace the genset control PCB (see Section 8).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-4

TABLE 10–1. TROUBLESHOOTING (CONT.)

Some genset service procedures present hazards that can result in severe per-

sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

OVERFREQUENCY FAULT—CODE NO. 14

(Controller not able to regulate to rated frequency)

Corrective Action:

1. Check the governor linkage for binding and service as necessary (see Governor Linkage and
Actuator in Section 6).

2. Check the governor controller board (see Section 9).

UNDERFREQUENCY FAULT—CODE NO. 15

(Controller not able to regulate to rated frequency)

Corrective Action:

1. Turn the genset line circuit breaker OFF. If the genset runs without shutting down, run the genset
with fewer connected loads.

2. Fill the LPG fuel tank if less than half full. On cold days the LPG container may have to be kept at
least half full to provide the rate of vaporization required to keep up with genset fuel demand. LPG
with more than 2.5 percent butane will not vaporize below 32

° F (0° C). Use HD-5 grade LPG.

3. Inspect/secure the spark plug cable on the spark plugs.

4. Service the air cleaner.

5. Check fuel solenoid valve operation (see Fuel System in Section 6).

6. Check the gas supply pressure and adjust as necessary (see Fuel System in Section 6).

7. Conduct the ignition system tests and service as necessary (see Ignition System in Section 6).

8. Check for a blocked exhaust system and service as necessary.

9. Check the governor linkage for binding and service as necessary (see Governor Linkage and
Actuator in Section 6).

10. Check magnetic pick-up for proper operation (See Section 6-5).

11. Check the governor controller board (see Section 9).

12. Conduct a cylinder compression test and service the engine if it is worn or malfunctioning.

13. Replace the genset control PCB (see Section 8).

AC OUTPUT SENSE FAULT—CODE NO. 27

(Controller unable to sense output voltage)

Corrective Action:

1. Check AC sense circuitry (Voltage Sense Input signal to genset control PCB) for continuity. See
Wiring Diagram in Section 11.

2. Check resistance of AC sense transformer:

H1 to H2 - 309 ohms

±10%

X1 to X2 - 391 ohms

±10%

3. Replace the genset control PCB (see Section 8).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-5

TABLE 10–1. TROUBLESHOOTING (CONT.)

Some genset service procedures present hazards that can result in severe per­sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

HIGH BATTERY VOLTAGE FAULT—CODE NO. 29

(Voltage across battery system greater than 17.5 volts)

Corrective Action:

1. Test the battery charging system and service as necessary.

LOW CRANKING SPEED FAULT—CODE NO. 32

(Cranking speed less than 180 rpm for more than 2 seconds)

Corrective Action (When engine is cranking slowly):

1. Clean and tighten the positive (+) and negative (–) battery cable connections at the battery and

at the genset.

2. Recharge or replace the battery. See the battery manufacturer’s recommendations.

3. Replace the engine oil with oil of proper viscosity for the ambient temperature (p. 2–1). (High oil
viscosity can slow cranking speed.)

4. Test the battery charging system and service as necessary.

Corrective Action (When engine appears to be cranking normally):

1. Disconnect genset control connector P1 (refer to Section 8 to remove connector P1) and check
for electrical continuity across pins P1-1 and P1-10 (field windings). If the circuit is open, service
the generator brush block and slip rings and repeat the test. Service or replace the generator
rotor if the circuit is still open (Section 7). (Speed sense signal is generated from this circuit.)

2. Disconnect genset control connector P1 and check for electrical continuity across pins P1-3 and
P1-9 (quadrature windings). Replace the generator stator assembly if the circuit is open (Section 7).

3. Replace the genset control PCB (see Section 8).

CONTROL CARD FAILURE FAULT—CODE NO. 35

(Microprocessor EEPROM error during self-test)

Corrective Action: Replace the genset control PCB (See Section 8).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-6

TABLE 10–1. TROUBLESHOOTING (CONT.)

Some genset service procedures present hazards that can result in severe per-

sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

MECHANICAL FAULT—CODE NO. 36

(Engine stopped without command by controller)

Corrective Action:

1. Fill the LPG fuel tank if less than half full. On cold days the LPG container may have to be kept at
least half full to provide the rate of vaporization required to keep up with genset fuel demand. LPG
with more than 2.5 percent butane will not vaporize below 32

° F (0° C). Use HD-5 grade LPG.

2. Inspect/secure the spark plug cable on the spark plugs.

3. Service the air cleaner.

4. Check continuity through S5 switch at idle and during operation.

5. Check fuel solenoid valve operation (see Fuel System in Section 6).

6. Check the gas supply pressure and adjust as necessary (see Fuel System in Section 6).

7. Disconnect genset control connector P1 (refer to Section 8 to remove connector P1) and check
for electrical continuity across pins P1-1 and P1-10 (field windings). If the circuit is open, service
the generator brush block and slip rings and repeat the test. Service or replace the generator
rotor if the circuit is still open (Section 7). (Speed sense signal is generated from Q1 - Q2 circuit.)

8. Check pin connections to controller.

9. Conduct the ignition system tests and service as necessary (see Ignition System in Section 6).

10. Check magnetic pick-up for proper operation (see Section 6).

11. Conduct a cylinder compression test and service the engine if it is worn or malfunctioning.

12. Replace the genset control PCB (see Section 8).

FIELD OVERLOAD FAULT—CODE NO. 38

(To many low power factor loads)

Corrective Action:

1. Reduce the number of appliances running at the same time, especially those with high motor
starting loads such as air conditioners.

2. Have air conditioners and other appliances checked for proper operation. (A locked compressor
rotor can cause very low power factor.)

3. Check pin connections.

4. Check brushes (see Section 7).

5. Test Rotor (see Section 7).

GENERATOR ROTOR FAULT—CODE NO. 41

(Controller failed to sense field voltage)

Corrective Action:

1. Check brushes (see Section 7).

2. Test rotor (see Testing the Generator in Section 7).

PROCESSOR FAULT—CODE NO. 42

(Microprocessor ROM error during self-test)

Corrective Action: Replace the genset control PCB (see Section 8).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-7

TABLE 10–1. TROUBLESHOOTING (CONT.)

Some genset service procedures present hazards that can result in severe per­sonal injury or death. Only qualified service personnel with knowledge of fuels, electricity,
and machinery hazards should perform genset service. See Safety Precautions.

PROCESSOR FAULT—CODE NO. 43

(Microprocessor RAM error during self-test)

Corrective Action: Replace the genset control PCB (see Section 8).

SPEED SENSE FAULT—CODE NO. 45

(Controller failed to sense quadrature frequency)

Corrective Action:

1. Check all pin connections and pin condition. Replace as necessary.

2. Disconnect genset control connector P1 (see Section 8 to remove connector P1) and check for
electrical continuity across pins P1-1 and P1-10 (field windings). If the circuit is open, service the
generator brush block and slip rings and repeat the test. Service or replace the generator rotor if
the circuit is still open (Section 7).

3. Disconnect genset control connector P1 and check for electrical continuity across pins P1-3 and
P1-9 (quadrature windings). Replace the generator stator assembly if the circuit is open (Section 7).

4. Replace the genset control PCB (see Section 8).

FIELD SENSE LOST FAULT—CODE NO. 48

(Controller failed to sense field voltage)

Corrective Action: Replace the genset control PCB (see Section 8).

▲

WARNING

!

Redistribution or publication of this document,

by any means, is strictly prohibited.

10-8

THIS PAGE LEFT INTENTIONALLY BLANK

Redistribution or publication of this document,

by any means, is strictly prohibited.

11-1

11. Wiring Diagrams

GENERAL

This section consists of the schematic and wiring
diagrams referenced in the text. the following
drawings are included:

• Page 11–2, Transfer Switch

• Page 11–3, Schematic Diagram

• Page 11–4, Genset Harness

• Page 11–5, Control Harness

11- 2

11- 3

11- 4

11- 5

Redistribution or publication of this document,

by any means, is strictly prohibited.