Generac Power Systems Portable Generator 004992 0 004992 1 User Manual

Owner’s Manual  
Liquid-cooled, Prepackaged  
Standby Generators  
Model Nos. 004992-0  
004992-1  
37kW NG, 40kW LP  
This manual should remain with the unit.  
ONLY QUALIFIED ELECTRICIANS OR CONTRACTORS  
SHOULD ATTEMPT INSTALLATION!!  
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Table of Contents  
Guardian 40kW Liquid-cooled Generators  
INTRODUCTION................................................IFC  
SAFETY RULES....................................................2  
Section 3 OPERATION ................................13  
3.1 Using an Engineered “GTS” Transfer Switch ......13  
3.2 Control Console Components..............................13  
3.3 Manual Transfer and Startup..............................14  
3.4 Engine Governor Adjustments ............................14  
3.5 Retransfer and Shutdown....................................15  
3.6 Automatic Operation ..........................................15  
3.7 Weekly Exercise Cycle..........................................15  
Section 4 — MAINTENANCE ..........................16  
Section 1 — GENERAL INFORMATION ............4  
1.1 Generator..............................................................4  
1.2 Transfer Switch ....................................................4  
1.3 Automatic System Operation ................................4  
1.4 Generator AC Connection Systems........................4  
1.5 Main Circuit Breaker ............................................4  
1.6 Generator Fuel System..........................................5  
1.7 Engine Protective Devices......................................5  
1.8 Unpacking ............................................................6  
1.9 Lifting the Generator ............................................6  
1.10 Specifications ........................................................7  
1.11 Fuel Consumption ................................................7  
1.12 Reconfiguring the Fuel System ..............................7  
1.13 Torque Specifications............................................8  
1.14 Engine Oil Recommendations ..............................8  
1.15 Coolant Recommendations....................................8  
1.16 Before Installation ................................................8  
Section 2 — INSTALLATION ............................8  
2.1 Standby Generator Installation ............................8  
2.2 Generator Location................................................9  
2.3 Generator Mounting and Support ........................9  
2.4 Basic Standby Electric System..............................9  
2.5 Emergency Circuit Isolation Method....................10  
2.6 Total Circuit Isolation Method ............................10  
2.7 Grounding the Generator ....................................10  
2.8 Generator AC Neutral Connections......................10  
2.9 Transfer Switch Start Signal Connections ..........10  
2.10 Battery Installation..............................................11  
2.11 Preparation Before Start-Up................................12  
4.1 Maintenance Performed by Authorized  
Service Facilities..................................................16  
4.2 Cooling System....................................................16  
4.3 Overload Protection for Engine DC  
Electrical System ................................................16  
4.4 Checking Fluid Levels ........................................16  
4.5 Maintenance Owner/Operator  
Can Perform........................................................17  
4.6 Miscellaneous Maintenance ................................18  
4.7 Scheduled Maintenance ......................................20  
Section 5 — TROUBLESHOOTING ..................23  
Section 6 — ELECTRICAL DATA ....................24  
Section 7 — EXPLODED VIEWS AND  
PARTS LISTS ..............................28  
Section 8 — INTALLATION DIAGRAM ............43  
Section 9 — NOTES ........................................44  
Section 10 — WARRANTY .................Back Cover  
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IMPORTANT SAFETY INSTRUCTIONS  
Guardian 40kW Liquid-cooled Generators  
SAVE THESE INSTRUCTIONS – The manufacturer suggests that these rules for safe  
operation be copied and posted in potential hazard areas. Safety should be stressed to all  
operators, potential operators, and service and repair technicians for this equipment.  
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SAVE THESE INSTRUCTIONS – This manual contains important instructions that should be  
followed during installation and maintenance of the generator and batteries.  
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GENERAL HAZARDS  
WARNING:  
The engine exhaust from this product  
contains chemicals known to the state  
of California to cause cancer, birth  
defects or other reproductive harm.  
For safety reasons, Generac recommends that this  
equipment be installed, serviced and repaired by an  
authorized service dealer or other competent, quali-  
fied electrician or installation technician who is famil-  
iar with applicable codes, standards and regulations.  
The operator also must comply with all such codes,  
standards and regulations.  
• Installation, operation, servicing and repair of this  
(and related) equipment must always comply with  
applicable codes, standards, laws and regulations.  
Adhere strictly to local, state and national electrical  
and building codes. Comply with regulations the  
Occupational Safety and Health Administration  
(OSHA) has established. Also, ensure that the gener-  
ator is installed, operated and serviced in accordance  
with the manufacturer’s instructions and recommen-  
dations. Following installation, do nothing that might  
render the unit unsafe or in noncompliance with the  
aforementioned codes, standards, laws and regula-  
tions.  
• The engine exhaust fumes contain carbon monoxide  
gas, which can be DEADLY. This dangerous gas, if  
breathed in sufficient concentrations, can cause  
unconsciousness or even death. For that reason, ade-  
quate ventilation must be provided. Exhaust gases  
must be piped safely away from any building or  
enclosure that houses the generator to an area where  
people, animals, etc., will not be harmed. This  
exhaust system must be installed properly, in strict  
compliance with applicable codes and standards.  
• Keep hands, feet, clothing, etc., away from drive belts,  
fans, and other moving or hot parts. Never remove  
any drive belt or fan guard while the unit is operating.  
• Adequate, unobstructed flow of cooling and ventilat-  
ing air is critical to prevent buildup of explosive gases  
and to ensure correct generator operation. Do not  
alter the installation or permit even partial blockage  
of ventilation provisions, as this can seriously affect  
safe operation of the generator.  
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!
WARNING:  
This product contains or emits chemicals  
known to the state of California to cause  
cancer, birth defects or other reproductive harm.  
Study these SAFETY RULES carefully before installing,  
operating or servicing this equipment. Become familiar  
with this Owner’s Manual and with the unit. The genera-  
tor can operate safely, efficiently and reliably only if it is  
properly installed, operated and maintained. Many acci-  
dents are caused by failing to follow simple and funda-  
mental rules or precautions.  
Generac cannot anticipate every possible circum-  
stance that might involve a hazard. The warnings in this  
manual, and on tags and decals affixed to the unit are,  
therefore, not all-inclusive. If using a procedure, work  
method or operating technique that Generac does not  
specifically recommend, ensure that it is safe for others.  
Also make sure the procedure, work method or operat-  
ing technique chosen does not render the generator  
unsafe.  
DANGER  
Despite the safe design of this generator,  
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operating this equipment imprudently, neglecting  
its maintenance or being careless can cause  
possible injury or death. Permit only responsible  
and capable persons to install, operate or main-  
tain this equipment.  
Potentially lethal voltages are generated by these  
machines. Ensure all steps are taken to render the  
machine safe before attempting to work on the  
generator.  
• Keep the area around the generator clean and unclut-  
tered. Remove any materials that could become haz-  
ardous.  
• When working on this equipment, remain alert at all  
times. Never work on the equipment when physically  
or mentally fatigued.  
Parts of the generator are rotating and/or hot  
during operation. Exercise care near running gen-  
!
erators.  
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IMPORTANT SAFETY INSTRUCTIONS  
Guardian 40kW Liquid-cooled Generators  
• Inspect the generator regularly, and promptly repair • Generators installed with an automatic transfer  
or replace all worn, damaged or defective parts using  
switch will crank and start automatically when NOR-  
MAL (UTILITY) source voltage is removed or is below  
an acceptable preset level. To prevent such automat-  
ic start-up and possible injury to personnel, disable  
the generator’s automatic start circuit (battery cables,  
etc.) before working on or around the unit. Then,  
place a “Do Not Operate” tag on the generator control  
panel and on the transfer switch.  
only factory-approved parts.  
• Before performing any maintenance on the generator,  
disconnect its battery cables to prevent accidental  
start-up. Disconnect the cable from the battery post  
indicated by a NEGATIVE, NEG or (–) first.  
Reconnect that cable last.  
• Never use the generator or any of its parts as a step.  
Stepping on the unit can stress and break parts, and  
may result in dangerous operating conditions from  
leaking exhaust gases, fuel leakage, oil leakage, etc.  
• In case of accident caused by electric shock, immedi-  
ately shut down the source of electrical power. If this  
is not possible, attempt to free the victim from the  
live conductor. AVOID DIRECT CONTACT WITH  
THE VICTIM. Use a nonconducting implement, such  
as a dry rope or board, to free the victim from the live  
conductor. If the victim is unconscious, apply first aid  
and get immediate medical help.  
• Never wear jewelry when working on this equipment.  
Jewelry can conduct electricity resulting in electric  
shock, or may get caught in moving components  
causing injury.  
ELECTRICAL HAZARDS  
• All generators covered by this manual produce dan-  
gerous electrical voltages and can cause fatal electrical  
shock. Utility power delivers extremely high and dan-  
gerous voltages to the transfer switch as well as the  
standby generator. Avoid contact with bare wires, ter-  
minals, connections, etc., on the generator as well as  
the transfer switch, if applicable. Ensure all appropri-  
ate covers, guards and barriers are in place before  
operating the generator. If work must be done around  
an operating unit, stand on an insulated, dry surface  
to reduce shock hazard.  
• Do not handle any kind of electrical device while  
standing in water, while barefoot, or while hands or  
feet are wet. DANGEROUS ELECTRICAL SHOCK  
MAY RESULT.  
• If people must stand on metal or concrete while  
installing, operating, servicing, adjusting or repairing  
this equipment, place insulative mats over a dry  
wooden platform. Work on the equipment only while  
standing on such insulative mats.  
FIRE HAZARDS  
• Keep a fire extinguisher near the generator at all  
times. Do NOT use any carbon tetra-chloride type  
extinguisher. Its fumes are toxic, and the liquid can  
deteriorate wiring insulation. Keep the extinguisher  
properly charged and be familiar with its use. If there  
are any questions pertaining to fire extinguishers,  
consult the local fire department.  
EXPLOSION HAZARDS  
• The National Electrical Code (NEC), Article 250  
requires the frame and external electrically conduc-  
tive parts of the generator to be connected to an  
approved earth ground and/or grounding rods. This  
grounding will help prevent dangerous electrical  
shock that might be caused by a ground fault condi-  
tion in the generator set or by static electricity. Never  
disconnect the ground wire.  
• Wire gauge sizes of electrical wiring, cables and cord  
sets must be adequate to handle the maximum elec-  
trical current (ampacity) to which they will be sub-  
jected.  
• Before installing or servicing this (and related) equip-  
ment, make sure that all power voltage supplies are  
positively turned off at their source. Failure to do so  
will result in hazardous and possibly fatal electrical  
shock.  
• Connecting this unit to an electrical system normally  
supplied by an electric utility shall be by means of a  
transfer switch so as to isolate the generator electric  
system from the electric utility distribution system  
when the generator is operating. Failure to isolate the  
two electric system power sources from each other by  
such means will result in damage to the generator  
and may also result in injury or death to utility power  
workers due to backfeed of electrical energy.  
• Properly ventilate any room or building housing the  
generator to prevent build-up of explosive gas.  
• Do not smoke around the generator. Wipe up any fuel  
or oil spills immediately. Ensure that no combustible  
materials are left in the generator compartment, or  
on or near the generator, as FIRE or EXPLOSION  
may result. Keep the area surrounding the generator  
clean and free from debris.  
• Generac generator sets may operate using one of sev-  
eral types of fuels. All fuel types are potentially FLAM-  
MABLE and/or EXPLOSIVE and should be handled  
with care. Comply with all laws regulating the storage  
and handling of fuels. Inspect the unit’s fuel system  
frequently and correct any leaks immediately. Fuel  
supply lines must be properly installed, purged and  
leak tested according to applicable fuel-gas codes  
before placing this equipment into service.  
• Diesel fuels are highly FLAMMABLE. Gaseous fluids  
such as natural gas and liquid propane (LP) gas are  
extremely EXPLOSIVE. Natural gas is lighter than air,  
and LP gas is heavier than air; install leak detectors  
accordingly.  
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Section 1 - General Information  
Guardian 40kW Liquid-cooled Generators  
1.1 GENERATOR  
1.3 AUTOMATIC SYSTEM OPERATION  
When this generator, along with a transfer switch, has  
been installed and interconnected, a circuit board in  
the generator panel constantly monitors UTILITY  
power source voltage. Should that voltage drop below  
a preset value, and remain at such a low state for a  
preset amount of time, the generator cranks and  
starts. After the generator starts, the transfer switch  
transfers load circuits so the generator can power  
them.  
This equipment is a liquid-cooled, engine-driven gen-  
erator set. The generator is designed to supply elec-  
trical power that operates critical electrical loads  
during utility power failure. The unit has been facto-  
ry-installed in a weather resistant, all metal enclosure  
and is intended for outdoor installation only. Use this  
generator as a source of electrical power for the oper-  
ation of 120 and/or 240VAC, single-phase loads.  
When utility source voltage has been restored, the  
switch re-transfers back to the UTILITY source volt-  
age and the generator then shuts down.  
If this generator is used to power electrical  
load circuits normally powered by a utility  
power source, it is required by code to install  
!
Please reference the transfer switch manual for spe-  
cific information.  
a transfer switch. The transfer switch must  
effectively isolate the electric system from the  
utility distribution system when the generator  
is operating (NEC 701). Failure to isolate an  
electrical system by such means results in  
damage to the generator and may also result  
in injury or even death to utility power work-  
ers due to backfeed of electrical energy.  
1.4 GENERATOR AC CONNECTION  
SYSTEMS  
The generator was shipped from the factory with its  
stator AC output leads connected in a single-phase,  
three-wire generator AC connection system (Figure  
1.1). The stator assembly in this system consists of a  
pair of stationary windings, with two leads brought  
out of each winding. Each single winding can supply  
120VAC, 60 Hertz. When the two windings are con-  
nected in series, a 240VAC, 60 Hertz AC output  
results. Typically the two HOT leads in the circuit are  
wires 11 and 44. The NEUTRAL leads are the junc-  
tion of Wires 22 and 33. The NEUTRAL is not  
grounded.  
1.2 TRANSFER SWITCH  
This generator system includes a matched 200 amp  
automatic transfer switch which is intended to be  
used in conjunction with the generator. It is supplied  
in a NEMA 3R enclosure. The NEMA 3R enclosure is  
weather resistant and can be used indoors or out-  
doors. Follow these rules:  
• Install the transfer switch on a firm, sturdy sup-  
porting structure.  
Figure 1.1 - Generator AC Connection System  
To prevent switch distortion, level the switch if nec-  
essary. This can be done by placing washers  
between the switch enclosure and the mounting  
surface.  
• Never install the switch where water or any corro-  
sive substance might drip onto the enclosure.  
• Protect the switch at all times against excessive  
moisture, dust, dirt, lint, construction grit and cor-  
rosive vapors.  
1.5 MAIN CIRCUIT BREAKER  
The generator’s main circuit breaker is included with  
the unit as shipped from the factory. The breaker for  
this unit is described in Figure 1.2.  
Figure 1.2 - Main Circuit Breaker  
Model  
004992-0  
Rating  
37,000 NG  
40,000 LP  
Phase  
Actual Current  
154.2  
C/B Rating*  
Circuit Breaker  
200A QN2  
1
1
200  
200  
166.7  
200A QN2  
* Amp Rating of C/B structured under model.  
®
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Section 1 - General Information  
Guardian 40kW Liquid-cooled Generators  
NOTE:  
1.6 GENERATOR FUEL SYSTEM  
The unit has been factory tested and adjusted using a  
natural gas fuel system. If propane (LP) gas is neces-  
sary, refer to Section 1.12 for conversion.  
The Low Oil Pressure, High Coolant Temperature  
and Low Coolant Level are not monitored for the  
first 10 seconds of engine run time.  
Fuel pressure for a natural gas set up should be five  
inches to 14 inches of water column (0.18 to 0.5  
psi) at all load ranges.  
Figure 1.4 - Low Oil Pressure Switch  
Fuel pressure for an LP vapor set up should be 11  
inches to 14 inches of water column (0.4 to 0.5  
psi) at all load ranges.  
NOTE:  
A seperate gas line and regulator may be needed  
to assure proper gas pressure to the generator.  
Improper gas pressure can cause hard starting and  
affect engine durability.  
Gaseous fuels such as natural and LP  
(propane) gas are highly explosive. Even the  
slightest spark can ignite such fuels and cause  
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1.7.2 HIGH COOLANT TEMPERATURE  
SWITCH  
Normally open (N.O.) thermostatic switch has sens-  
ing tip which is immersed in captive coolant. Should  
coolant temperature exceed about 230°F (110°C), the  
switch contacts close. This causes the engine to shut  
down automatically and turns on the high coolant  
temperature/low coolant level LED (Figure 1.5).  
an explosion. No leakage of fuel is permitted.  
Natural gas, which is lighter than air, tends to  
collect in high areas. LP gas is heavier than air  
and tends to settle in low areas.  
1.7 ENGINE PROTECTIVE DEVICES  
The engine has several safety switches which cause  
the engine to automatically shut down under the fol-  
lowing conditions: low oil pressure, high coolant tem-  
perature, engine overspeed, low coolant level or over-  
crank (Figure 1.3).  
Figure 1.5- High Coolant Temperature Switch  
Figure 1.3 - Engine Protective Devices  
Low Oil Pressure Switch  
High Coolant  
Temperature Switch  
Low Coolant  
Level Sensor  
1.7.3 LOW COOLANT LEVEL SWITCH  
Should engine coolant level drop below the level of  
the high coolant temperature switch, it is possible for  
the engine to overheat without automatic shutdown.  
To prevent such overheating without automatic shut  
down, the engine has a low coolant level sensor. If the  
engine coolant drops too low, the engine automatical-  
ly shuts down and turns on the high coolant temper-  
ature/low coolant level LED (Figure 1.6 on page 6).  
1.7.1 LOW OIL PRESSURE SWITCH  
This switch is normally-closed (N.C.) but is held open  
by engine oil pressure during engine running. Should  
operating oil pressure drop below about 8-10 psi  
(55-68 kPa), the switch contacts close, the engine  
shuts down automatically, and the low oil pressure  
LED is turned ON (Figure 1.4).  
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Section 1 — General Information  
Guardian 40kW Liquid-cooled Generators  
Figure 1.6 - Low Coolant Level Sensor  
1.7.7 LOW BATTERY  
The engine control board continually monitors the  
battery voltage and turns on the low battery LED if  
the battery voltage falls below 11.0 VDC for one  
minute. Low battery voltage is a non-latching alarm,  
which will automatically clear if the battery voltage  
rises above 11.0 VDC.  
The control system will not attempt to start the  
engine if there is a low battery condition, however, if  
the engine is already running when the low battery  
condition occurs, the engine will continue to run as  
long as possible.  
1.7.4 OVERSPEED SHUTDOWN  
Battery voltage is NOT monitored during the crank  
cycle.  
The engine control board receives AC frequency sig-  
nals from an engine run winding in the alternator.  
Should AC frequency exceed about 72 Hertz for three  
seconds or 75 Hertz instantaneously, the engine  
shuts down and the overspeed LED turns on. Should  
AC frequency exceed about 72 Hertz, circuit board  
action will automatically shutdown the engine (Figure  
1.7).  
1.7.8 ALARM RESET  
If the engine control board shuts down the generator  
for any of the above reasons, the engine remains  
stopped until the alarm is cleared by placing the  
AUTO/OFF/MANUAL switch into the OFF position.  
1.7.9 DC FUSE  
Figure 1.7 - Printed Circuit Board Assembly  
These fuses are located on the front panel of the con-  
trol system. They protect the panel wiring and com-  
ponents from damaging overload. Always remove the  
15 amp main fuse before working on the generator.  
The unit will not start or crank if this fuse is blown.  
Replace the fuse with one of the same size, type, and  
rating (main AGC-15, battery charger AG4).  
R44  
LED1  
C27  
Q2  
C9  
J2  
C26  
U7  
C4  
D10  
C21  
1.8 UNPACKING  
C30  
C2  
1.8.1 UNPACKING PRECAUTIONS  
Handle shipping cartons and crates with care. Use  
care to avoid damage from dropping, bumping, colli-  
sion, etc..  
RL1  
RL2  
R1  
R48  
D17  
R49  
U1  
J1  
L3  
D19  
.
R E V 9 0 6 E 0 4 B #  
1.8.2 INSPECTION  
After unpacking, carefully inspect the generator for  
any damage that may have occurred during ship-  
ment. If loss or damage is noted at the time of deliv-  
ery, have the person(s) making delivery note all dam-  
age on the freight bill or affix his signature under the  
consignor’s memo of loss or damage.  
1.7.5 RPM SENSOR LOSS  
If the engine control board does not receive a proper  
rpm signal from the starter during cranking or run-  
ning, it shuts down the engine on rpm sensor loss  
and flash the overspeed LED.  
1.7.6 OVERCRANK SHUTDOWN  
1.9 LIFTING THE GENERATOR  
The engine control board uses a cyclic cranking  
process when attempting to start the engine. The first  
crank cycle is a 15-second crank followed by a seven-  
second rest. This is followed by five more crank  
cycles each with a seven second crank followed by a  
seven-second rest.  
When lifting or hoisting equipment is used,  
be careful not to touch overhead power lines.  
The generators weight of more than 1400  
!
pounds requires proper tools, equipment, and  
qualified personnel to be used in all phases of  
handling and unpacking.  
If the engine fails to start after all six attempts, the  
start attempt is stopped and the overcrank LED  
turned on.  
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Section 1 — General Information  
Guardian 40kW Liquid-cooled Generators  
Fuel pressure for a natural gas set up should be five  
inches to 14 inches of water column (0.18 to 0.5  
psi) at all load ranges.  
1.10 SPECIFICATIONS  
1.10.1 GENERATOR SPECIFICATIONS  
Fuel pressure for an LP vapor set up should be 11  
inches to 14 inches of water column (0.4 to 0.5  
psi) at all load ranges.  
Single-phase  
Model  
Rated Max. Cont.  
4992-0  
37 (NG), 40 (LP)  
AC Power Output (kW)  
Rated voltage (volts)  
No. of Rotor Poles  
Driven Speed of Rotor  
Rotor Excitation System  
Type of Stator  
1.12 RECONFIGURING THE FUEL  
120/240  
4
1800  
SYSTEM  
Fuel pressure for both natural gas and liquid  
propane set ups should be 11 inches to 14 inches of  
water column (0.4 to 0.5 psi) at all load ranges.  
Direct excited brush type  
4 Wire  
Rotor/Stator Insulation  
Class F/H  
NOTE:  
1.10.2 ENGINE SPECIFICATIONS  
All models are configured for natural gas from the  
factory.  
Make..................................................................................................Chrysler  
Displacement ....................................................................................3.9 liters  
Cylinder Arrangement ..............................................................................V-6  
Valve Arrangement................................................................Overhead Valve  
Firing Order ..................................................................................1-6-5-4-3-2  
Number of Main Bearings ............................................................................4  
Compression Ratio ............................................................................9.1 to 1  
No. of Teeth on Flywheel ..........................................................................164  
Ignition Timing at 1800 rpm ..............................................30 degrees BTDC  
Spark Plug Gap................................................................1.01mm (0.040 in.)  
Recommended Spark Plugs  
Champion......................................................................................RC12LC4  
Oil Pressure ....................................................................................30-80 psi  
Crankcase Oil Capacity ........................................4.0 U.S. quarts (3.8 liters)  
Recommended Engine Oil ........................................................SAE 15W-40  
Type of Cooling System ..................................Pressurized, closed recovery  
Cooling Fan ................................................................................Pusher Type  
Cooling System Capacity ..................................5.0 U.S. gallons (19.3 liters)  
To reconfigure the fuel system from NG to LP vapor,  
follow these steps:  
1. Turn the main gas supply off.  
2. Remove the carburetor fuel hose from the outlet  
port (Port 1) of the demand regulator (Figure  
1.8).  
3. Remove the brass hose fitting from the outlet port  
(Port 1) of the demand regulator.  
4. Remove pipe plug from Port 2.  
5. Install brass hose fitting into Port 2.  
6. Install pipe plug into Port 1.  
7. Connect carburetor gas hose to brass fitting.  
8. Tighten all clamps and plugs.  
9. Make sure fuel supply is of the proper pressure  
and type for configuration.  
10. Reverse the procedure to convert back to natural  
Recommended Coolant ............................................Use a 50-50 mixture of  
gas.  
ethylene glycol base  
and de-ionized water.  
Figure 1.8 — Reconfigure the Fuel System  
Port 1  
Port 2  
1.11 FUEL CONSUMPTION  
FUEL HOSE  
FUEL HOSE  
Natural Gas:  
BRASS HOSE  
FITTING  
BRASS HOSE  
FITTING  
% of Load  
25%  
4.1  
50%  
7.7  
75%  
11.0  
100%  
14.2  
PLUG  
PLUG  
OUT  
PORT 1  
OUT  
PORT 2  
3
m /hr  
3
HOUSING  
PORTS  
HOUSING  
PORTS  
ft /hr  
143.1  
271.1  
388.5  
502.0  
LP Vapor:  
% of Load  
25%  
1.7  
50%  
3.3  
75%  
4.7  
100%  
6.0  
3
m /hr  
3
ft /hr  
60.7  
115.0  
164.9  
213.0  
NOTE:  
Fuel consumption is given at rated maximum con-  
tinuous power output when using natural gas rated  
at 1000 Btu per cubic foot. LP gas is rated at 2520  
Btu per cubic foot. Actual fuel consumption  
obtained may vary depending on such variables as  
applied load, ambient temperature, engine condi-  
tions and other environmental factors.  
NG FUEL SYSTEM  
LP FUEL SYSTEM  
NOTE:  
Port 1 is for NG only and Port 2 is for LP vapor  
only. No provision for dual fuel has been made.  
®
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Section 2 — Installation  
Guardian 40kW Liquid-cooled Generators  
DANGER  
Serious injury or damage may occur if not  
configured properly. Please consult an author-  
ized service dealer with any questions.  
Do not use any chromate base rust inhibitor  
with ethylene glycol base anti-freeze or  
chromiumhydroxide (“green slime”) forms and  
will cause overheating. Engines that have  
been operated with a chromate base rust  
inhibitor must be chemically cleaned before  
adding ethylene glycol base anti-freeze. Using  
any high silicate anti-freeze boosters or addi-  
tives will also cause overheating. It is also rec-  
ommend that any soluble oil inhibitor is NOT  
USED for this equipment.  
!
!
1.13 TORQUE SPECIFICATIONS  
Tighten the bolts from the middle out, in a criss-  
cross pattern.  
Cylinder Head ....................................50 ft.lb./105 ft.lb./105 ft.lb.  
Intake Manifold ....................................48 in.lb./84 in.lb./84 in.lb.  
Exhaust Manifold..............................................................25 ft.lb.  
1.14 ENGINE OIL RECOMMENDATIONS  
The unit has been filled with 5W-20 engine oil at the  
factory. Use a high-quality detergent oil classified “For  
Service CC, SD, SE, SF.” Detergent oils keep the  
engine cleaner and reduce carbon deposits. Use oil  
having the following SAE viscosity rating, based on  
the ambient temperature range anticipated before the  
next oil change:  
1.16 BEFORE INSTALLATION  
Before installing this equipment, check the ratings of  
both the generator and the transfer switch. Read  
“Emergency Isolation Method” and “Total Circuit  
Isolation Method” in Sections 2.5 and 2.6.  
The generator’s rated wattage/amperage capacity  
must be adequate to handle all electrical loads that  
the unit will power. The critical (essential) loads may  
need to be grouped together and wired into a sepa-  
rate “emergency” distribution panel.  
Temperature  
Above 80° F (27° C)  
32° to 80° F (-1° to 27° C)  
Below 32° F (0° C)  
Oil Grade (Recommended)  
SAE 15W-40  
SAE 15W-40  
SAE 15W-40  
The standard transfer switch has no sensing or con-  
trolling circuit boards. Instead, the generator control  
console houses a “Printed Circuit Board Assembly”,  
which controls all phases of operation, including  
engine start up and load transfer.  
NOTE:  
Synthetic oil is highly recommended in any ele-  
ment with temperatures above 90° F or below 30°  
F.  
2.1 STANDBY GENERATOR  
INSTALLATION  
Any attempt to crank or start the engine  
DANGER  
before it has been properly serviced with the  
recommended oil may result in an engine fail-  
!
Connecting this generator to an electrical sys-  
tem normally supplied by an electric utility  
shall be by means of a transfer switch, so as to  
isolate the electric system from the utility distri-  
bution system when the generator is operating.  
Failure to isolate the electric system by these  
means will result in damage to the generator  
and may also result in injury or death to utility  
workers due to backfeed of electrical energy.  
ure.  
1.15 COOLANT RECOMMENDATIONS  
Use a mixture of half low silicate ethylene glycol base  
anti-freeze and half de-ionized water. Cooling system  
capacity is about 20 U.S. quarts (19.3 liters). Use  
only de-ionized water and only low silicate anti-  
freeze. If desired, add a high quality rust inhibitor to  
the recommended coolant mixture. When adding  
coolant, always add the recommended 50-50 mix-  
ture.  
If an open bottom is used, the engine-genera-  
tor is to be installed over non-combustible  
materials and should be located such that com-  
bustible materials are not capable of accumu-  
lating under the generator set.  
Only qualified, competent installation contractors or  
electricians thoroughly familiar with applicable  
codes, standards and regulations should install this  
standby electric power system. The installation must  
comply strictly with all codes, standards and regula-  
tions pertaining to the installation.  
®
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Section 2 — Installation  
Guardian 40kW Liquid-cooled Generators  
2.2 GENERATOR LOCATION  
Install the generator set, in its protective enclosure  
outdoors, where adequate cooling and ventilating air  
always is available. Consider these factors:  
After the system has been installed, do nothing  
that might render the installation in noncompli-  
ance with such codes, standards and regula-  
tions.  
!
• Install the unit where air inlet and outlet openings  
will not become obstructed by leaves, grass, snow,  
etc. If prevailing winds will cause blowing or drift-  
ing, consider using a windbreak to protect the unit.  
• Install the generator on high ground where water  
levels will not rise and endanger it.  
• This genset must be installed on a level surface.  
The base frame must be level within 1/2 inch all  
around.  
2.1.1 NFPA STANDARDS  
The following published standards booklets pertain-  
ing to standby electric systems are available form the  
National Fire Protection Association (NFPA),  
Batterymarch Park, Quincy, MA 02269:  
NOTE:  
• Allow sufficient room on all sides of the generator  
for maintenance and servicing. A good rule is to  
allow five feet of space on all sides.  
• Where strong prevailing winds blow from one  
direction, face the generator air inlet openings into  
the prevailing winds.  
• Install the generator as close as possible to the  
transfer switch. This reduces the length of wiring  
and conduit.  
It is essential to use the latest version of any stan-  
dard to ensure correct and current information.  
• NFPA No. 37, STATIONARY COMBUSTION  
ENGINES AND GAS TURBINES.  
• NFPA No. 76A, ESSENTIAL ELECTRICAL SYS-  
TEMS FOR HEALTH CARE FACILITIES.  
• NFPA No. 220, STANDARD TYPES OF BUILDING  
CONSTRUCTION  
• NFPA No. 68, GUIDE FOR EXPLOSION VENTING  
• NFPA No. 70, NATIONAL ELECTRICAL CODE.  
• NFPA No. 30, FLAMMABLE AND COMBUSTIBLE  
LIQUIDS CODE.  
• Install the generator as close as possible to the fuel  
supply, to reduce the length of piping. HOWEVER,  
REMEMBER THAT LAWS OR CODES MAY REG-  
ULATE THE DISTANCE.  
• NFPA No. 10, INSTALLATION, MAINTENANCE AND  
2.3 GENERATOR MOUNTING AND  
USE OF PORTABLE FIRE EXTINGUISHERS.  
SUPPORT  
2.1.2 OTHER PUBLISHED STANDARDS  
Retain the generator compartment to a concrete slab  
with 1/4-inch masonry type anchor bolts. Be sure the  
bolts are long enough to retain the compartment. The  
slab should be at least six inches thick and should  
extend beyond the enclosure to a distance of at least  
three inches on all sides. See Section 6 for generator  
major dimensions.  
In addition to NFPA standards, the following infor-  
mation pertaining to the installation and use of  
standby electric systems is available:  
NOTE:  
It is essential to use the latest version of any stan-  
dard to ensure correct and current information.  
• Article X, NATIONAL BUILDING CODE, available  
from the American Insurance Association, 85 John  
Street, New York, N.Y. 10038.  
• AGRICULTURAL WIRING HANDBOOK, obtainable  
from the Food and Energy Council, 909 University  
Avenue, Columbia, MO, 65201.  
• ASAE EP-364.2, INSTALLATION AND MAINTE-  
NANCE OF FARM STANDBY ELECTRIC POWER,  
available from the American Society of Agricultural  
Engineers, 2950 Niles Road, St. Joseph, MI 49085.  
• A52.1, AMERICAN NATIONAL STANDARD FOR  
CHIMNEYS, FIREPLACES AND VENTING SYS-  
TEMS, available from the American National  
Standard Institute, 1430 Broadway, New York, N.Y.  
10018.  
2.4 BASIC STANDBY ELECTRIC  
SYSTEM  
Figure 2.1 (on page 10) shows a schematic diagram  
of a basic standby electric system. Both the UTILITY  
power supply and the STANDBY (GENERATOR) out-  
put are connected to an approved transfer switch.  
The transfer switch is required by electrical code and  
serves the following functions:  
• Allows the LOAD circuits to be connected to only  
one power supply at a time.  
• Prevents electrical backfeed between the generator  
and the UTILITY power circuits.  
Notice that both the STANDBY and the UTILITY  
power supplies to the transfer switch are protected  
against overload by a main line circuit breaker.  
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Section 2 — Installation  
Guardian 40kW Liquid-cooled Generators  
Figure 2.1 – Basic Standby Electric System  
2.7 GROUNDING THE GENERATOR  
The National Electrical Code requires the frame and  
external electrically conductive parts of this equip-  
ment to be properly connected to an approved earth  
ground and/or grounding rods. For that purpose, a  
GROUND LUG (Figure 2.2) is provided on the gener-  
ator mounting base. Consult a qualified electrician  
for grounding requirements in the area. Grounding  
procedures must meet local regulations.  
DANGER  
Do not connect the ground wire to any pipe  
that carries a flammable or explosive substance  
– FIRE or an EXPLOSION may result.  
2.5 EMERGENCY CIRCUIT ISOLATION  
Proper grounding helps protect personnel against  
electrical shock in the event of a ground fault condi-  
tion in the generator or in connected electrical  
devices. In addition, grounding helps dissipate static  
electricity that often builds up in ungrounded  
devices.  
METHOD  
This prevents overloading the generator by keeping  
electrical loads below the wattage/amperage capacity  
of the generator. If the generator is powering only crit-  
ical loads, within the wattage/amperage capacity, dur-  
ing utility power outages, consider using the emer-  
gency circuit isolation method.  
Figure 2.2 – Generator Grounding Lug (typical)  
Critical electrical loads are grouped together and  
wired into a separate “Emergency Distribution  
Panel.” Load circuits powered by that panel are with-  
in the wattage/amperage capacity of the generator set.  
When this method is used, it is difficult to overload  
the generator. The transfer switch must meet the fol-  
lowing requirements:  
• It must have an ampere rating equal to the total  
amperage rating of the emergency distribution  
panel circuit.  
• Have it installed between the building’s main dis-  
tribution panel and the emergency distribution  
panel.  
GROUNDING  
LUG  
2.6 TOTAL CIRCUIT ISOLATION  
METHOD  
2.8 GENERATOR AC NEUTRAL  
When a generator capable of powering all electrical  
loads in the circuit is to be installed, use the “Total  
Circuit Isolation Method.” It is possible for the gener-  
ator to be overloaded when this isolation method is  
employed. The following apply to the transfer switch  
in this type of system.  
CONNECTIONS  
Generac uses an UNGROUNDED AC neutral.  
Grounding is recommended only at the main service  
entrance. If the neutral wire is grounded and one of  
the phase loads becomes grounded, the excessive  
current opens the load circuit breaker or collapses  
the generator field. The actual result depends on the  
electrical characteristics of the particular installed  
generator.  
• Ampere rating of the transfer switch must equal  
the ampere rating of the normal incoming utility  
service.  
• The transfer switch is installed between the utility  
service entrance and the building distribution  
panel.  
• In accordance wtih electrical code, an approved  
means of service disconnect must be installed  
between the normal incoming utiltiy service  
entrance and the transfer switch.  
Failure to connect the generator neutral prop-  
!
erly will result in unbalanced line-to-neutral  
voltages. Resulting high voltages will cause  
equipment damage.  
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Section 2 — Installation  
Guardian 40kW Liquid-cooled Generators  
2.9 TRANSFER SWITCH SIGNAL  
CONNECTIONS  
2.10 BATTERY INSTALLATION  
DANGER  
Standby generators installed with automatic  
transfer switches will crank and start automati-  
2.9.1 PRE-PACKAGED ATS  
!
If the generator is to be installed with a pre-packaged  
transfer switch, it is necessary to connect the control  
wires to the generator and set position two of the  
four-position dip switch to OFF.  
cally when NORMAL (UTILITY) source voltage is  
removed or is below an acceptable preset level.  
To prevent such automatic start-up and possible  
injury to personnel, do not connect battery  
cables until certain that normal source voltage  
at the transfer switch is correct and the system  
is ready to be placed into operation.  
Setting switch two to OFF allows the control PCB to  
perform the ATS control functions.  
Control system interconnections consist of N1 and  
N2, and leads 23 and 194. Control system intercon-  
nection leads must be run in a conduit that is sepa-  
rate from the AC power lead. Recommended wire  
gauge sizes for this wiring depends on the length of  
the wire, as recommended below:  
Storage batteries give off explosive hydrogen  
gas. This gas can form an explosive mixture  
around the battery for several hours after  
charging. The slightest spark can ignite the gas  
and cause an explosion. Such an explosion can  
shatter the battery and cause blindness or  
other injury. Any area that houses a storage  
battery must be properly ventilated. Do not  
allow smoking, open flame, sparks or any spark  
producing tools or equipment near the battery.  
MAXIMUM WIRE LENGTH  
RECOMMENDED WIRE  
SIZE  
460 feet (140m)  
No. 18 AWG.  
No. 16 AWG.  
No. 14 AWG.  
No. 12 AWG.  
461 to 730 feet (223m)  
731 to 1,160 feet (354m)  
1,161 to 1,850 feet (565m)  
Battery electrolyte fluid is an extremely caustic  
sulfuric acid solution that can cause severe  
!
burns. Do not permit fluid to contact eyes, skin,  
clothing, painted surfaces, etc. Wear protective  
goggles, protective clothing and gloves when  
handling a battery. If fluid is spilled, flush the  
affected area immediately with clear water.  
2.9.2 GTS-TYPE ATS  
If the generator is to be installed with an engineered  
automatic transfer switch, such as a Generac GTS-  
type switch, it is necessary to connect the two-wire  
start control system.  
Connect the two-wire start signal from the automatic  
transfer switch to the automatic start connection,  
which is located in the middle, on the bottom, inside  
the control panel. Match wires 178 and 183 in the  
transfer switch to 178 and 183 on the terminal strip  
in the control panel. The conductors for the two-wire  
start circuit must be in their own conduit. (See  
Section 3.1 for further explanation.)  
Do not dispose of the battery in a fire. The bat-  
tery is capable of exploding.  
Do not open or mutilate the battery. Released  
electrolyte can be toxic and harmful to the skin  
and eyes.  
!
The battery represents a risk of high short circuit  
current. When working on the battery, always  
remove watches, rings or other metal objects,  
and only use tools that have insulated handles.  
NOTE:  
It will be necessary to provide a UTILITY supply to  
the integral battery charger. This battery charger  
is located in the engine generator control panel.  
Locate the six position terminal strip in the con-  
trol panel. Connect a 240 VAC UTILITY supplied  
source to terminals labeled N1 and N2. The 240  
VAC circuit should be protected by a 15A maxi-  
mum rated circuit breaker.  
2.10.1 VENTED BATTERIES  
The electrolyte is a dilute sulfuric acid that is  
harmful to the skin and eyes. It is electrically  
conductive and corrosive. The following proce-  
dures are to be observed:  
!
• Wear full eye protection and protective clothing,  
• Where electrolyte contacts the skin, wash it off  
immediately with water,  
• Where electrolyte contacts the eyes, flush thor-  
oughly and immediately with water and seek med-  
ical attention, and  
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Section 2 — Installation  
Guardian 40kW Liquid-cooled Generators  
Before starting the generator for the first time, the  
installer must complete the following procedures. For  
follow-up maintenance information and/or service  
intervals, please refer to Section 4, “Maintenance.”  
• Spilled electrolyte is to be washed down with an  
acid-neutralizing agent. A common practice is to  
use a solution of one pound (500 grams) bicarbon-  
ate of soda to one gallon (4 liters) of water. The  
bicarbonate of soda solution is to be added until  
the evidence of reaction (foaming) has ceased. The  
resulting liquid is to be flushed with water and the  
area dried.  
2.11.2 TRANSFER SWITCH  
If this generator is used to supply power to any elec-  
trical system normally powered by an electric utility,  
the National Electrical Code requires that a transfer  
switch be installed. The transfer switch prevents elec-  
trical backfeed between two different electrical sys-  
tems (for additional information, see the applicable  
transfer switch manual for this unit). The transfer  
switch, as well as the generator and other standby  
components, must be properly located and mounted  
in strict compliance with applicable codes, standards  
and regulations.  
Lead acid batteries present a risk of fire  
because they generate hydrogen gas. The fol-  
lowing procedure are to be followed:  
• DO NOT SMOKE when near batteries,  
• DO NOT cause flame or spark in battery area, and  
• Discharge static electricity from body before touch-  
ing batteries by first touching a grounded metal  
surface.  
Servicing of batteries is to be performed or super-  
vised by personnel knowledgeable of batteries and  
the required precautions. Keep unauthorized person-  
nel away from batteries.  
2.11.3 FUEL SYSTEM  
Make sure the fuel supply system to the generator (a)  
delivers the correct fuel at the correct pressure and  
(b) is properly purged and leak tested according to  
code. No fuel leakage is permitted. See  
“Specifications” (Section 1.10) for more information.  
The recommended battery is Group 27F, 12V nega-  
tive ground, 700 CCA/90 AH minimum capacity. All  
batteries must be at 100 percent state-of-charge  
before they are installed on the generator.  
When using maintenance-free batteries, it is not nec-  
essary to check the specific gravity or electrolyte level.  
Have these procedures performed at the intervals  
specified in Section 4, “Maintenance.” A negative  
ground system is used. Battery connections are  
shown on the wiring diagrams. Make sure all batter-  
ies are correctly connected and terminals are tight.  
Observe battery polarity when connecting batteries to  
the generator set.  
2.11.4 GENERATOR SET LUBRICATION  
Check the engine crankcase oil level before operating  
and add oil to the proper level – the dipstick “FULL”  
mark. Never operate the engine with the oil level  
below the dipstick ADD” mark. See “Specifications”  
(Section 1.10) and “Engine Oil Recommendations”  
(Section 1.14).  
NOTE:  
NOTE:  
Damage will result if the battery connections are  
This engine is shipped from the manufacturer  
with 5W-20 oil. This oil should be changed after  
30 hours of operation.  
made in reverse.  
2.11 PREPARATION BEFORE START-UP  
The instructions in this section assume that the  
standby generator has been properly installed, serv-  
iced, tested, adjusted and otherwise prepared for use  
by a competent, qualified installation contractor. Be  
sure to read the “Safety Rules” on pages 2 and 3, as  
well as all other safety information in this manual,  
before attempting to operate this (and related) equip-  
ment.  
2.11.5 ENGINE COOLANT  
Have the engine cooling system properly filled with  
the recommended coolant mixture. Check the system  
for leaks and other problems. See “Specifications”  
(Section 1.10) and “Coolant” (Section 1.15).  
2.11.6 BELT TENSION  
Check the engine fan belt tension and condition prior  
to placing the unit into service and at recommended  
intervals. Belt tension is correct when a force of  
approximately 22 pounds (10 kg), applied midway  
between pulleys, deflects the belt about 3/8- to 5/8-  
inch (10 to 16 mm).  
2.11.1 PRIOR TO INITIAL START-UP  
Prior to initially starting the generator, it must  
be properly prepared for use. Any attempt to  
crank or start the engine before it has been  
properly serviced with the recommended types  
and quantities of engine fluids (oil, coolant,  
!
2.11.7 ELECTRICAL SYSTEM  
Make sure the generator is properly connected to an  
approved earth ground and/or ground rod.  
fuel, etc.) may result in an engine failure.  
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Section 3 - Operation  
Guardian 40kW Liquid-cooled Generators  
Make sure the generator battery is fully charged, prop-  
erly installed and interconnected, and ready for use.  
3.2 CONTROL CONSOLE  
COMPONENTS  
Check to ensure that there are no loose electrical con-  
nections. Restrain any loose wires to keep them clear  
of any moving generator set components.  
The components of a home standby generator control  
console (Figure 3.1) are as follows:  
Figure 3.1 - Home Standby Generator Panel  
3.1 USING AN ENGINEERED “GTS”  
TRANSFER SWITCH  
LED INDICATORS:  
FLASHING GREEN LED  
=
NO UTILITY SENSE  
When required, the pre-packaged standby generator  
can be installed with an engineered Generac “GTS”  
type automatic transfer switch.  
5
FLASHING RED LED'S  
=
EXERCISER NOT SET  
(IN AUTO MODE ONLY) SOLID GREEN LED  
RED LED'S INDIVIDUAL FAULT  
=
SYSTEM READY, UTILITY POWER ON  
=
(SEE OWNER'S MANUAL FOR COMPLETE LED DETAILS)  
OVER CRANK  
RED LED  
E
E
In this application, the GTS is responsible for utility  
sensing, weekly exercising, and load transferring.  
AUTO  
OFF  
OFF  
ON  
SET  
EXECISER  
TIME  
SET  
EXERCISE  
TIME  
MANUAL  
GREEN LED  
TO SET EXERCISER TIME  
1) PLACE AUTO/OFF/MANUAL SWITCH TO AUTO POSITION.  
Position two of the four-position dip switch is used to  
turn over this control to the GTS.  
0E7194  
SWITCH  
Pos2 ON — GTS Application  
AUTO/OFF/MANUAL  
SWITCH  
• The control board will NOT monitor utility.  
• The control board will NOT perform a weekly exer-  
cise. (The five red LEDs will not flash in this  
mode.)  
4A FUSE  
BATTERY  
CHARGER  
15A FUSE  
MAIN  
POWER  
• The control board will NOT activate the transfer  
3.2.1 AUTO/OFF/MANUAL SWITCH  
output.  
• The control board WILL monitor all engine condi-  
tions and shut down on all the faults listed in this  
document.  
Use this three-position switch as follows:  
• Set the switch to AUTO for fully automatic opera-  
tion. See Automatic Operation” (Section 3.5).  
• Set switch to MANUAL position to crank and start  
the generator engine.  
• Set switch to OFF position to shut down an oper-  
ating engine. With OFF selected, operation will not  
be possible.  
Pos2 OFF — ATS Application (Included switch)  
• The control board will perform all of the automat-  
ic features listed in this document.  
• The two-wire start connections should NOT be  
used.  
GTS Mode Operation  
DANGER  
When in GTS mode, the control board will respond  
as follows based on the AUTO/OFF/MANUAL switch  
position.  
With switch set to AUTO, engine can crank  
and start suddenly without warning. Such  
automatic start up normally occurs when utili-  
ty source voltage drops below a pre-set level.  
To prevent possible injury that might be  
caused by such sudden starts, set AUTO/OFF/  
MANUAL switch to OFF before working on or  
around the unit. Then, place a “DO NOT  
OPERATE” tag on control console.  
!
OFF — The generator will not start and run in this  
position.  
MANUAL — The control board will start and run the  
generator whenever the switch is in the manual posi-  
tion.  
AUTO — The control board will monitor the two-wire  
start circuit. When a two-wire start is issued the con-  
trol board will immediately start and run the genera-  
tor. Whe the two-wire start is removed the control  
board will immediately stop the generator.  
3.2.2 FAULT INDICATOR LEDS  
These LEDs turn ON when one of the following  
engine faults occurs and the engine shuts down.  
• Low Oil Pressure  
• Overcrank  
NOTE:  
If the generator is installed in conjunction with an  
engineered GTS type transfer switch, refer to the  
applicable transfer switch manual for exact oper-  
ating parameters and timing sequences.  
• Low Battery  
• Overspeed/RPM Sensor Loss  
• High Coolant Temperature/Low Coolant Level  
See Section 1.7 for further explanation of engine pro-  
tection functions.  
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Section 3 — Operation  
Guardian 40kW Liquid-cooled Generators  
3.2.3 15 AMP FUSE  
3.4 ENGINE GOVERNOR  
Fuse protects the control console’s DC control circuit  
against electrical overload. If the fuse has melted  
open because of an overload, engine cranking and  
startup cannot occur. If the fuse needs to be replaced,  
use only an identical 15-amp replacement fuse. (Type  
AGC)  
ADJUSTMENTS  
Engine speed governing is also controlled by the  
engine control board. Connector J2 on the engine  
control board interfaces with a governor driver mod-  
ule and the Bosch throttle body. The engine governor  
has been set by the factory during final testing of the  
generator and, in most cases, should not be adjusted.  
3.2.4 4.0 AMP INLINE FUSE  
This fuse protects the battery charger against electri-  
cal overload. If the fuse needs to be replaced, use only  
an identical 4 amp replacement fuse (type AG).  
If, however, adjustments are necessary, or a new  
engine control board is installed in the generator, the  
following procedure should be followed (Figure 3.2):  
1. Set all three potentiometers (pots) fully counter-  
clockwise.  
NOTE:  
2. Under no load condition, increase the GAIN pot  
as much as possible without causeing instability.  
3. Apply 1/4, 1/2, 3/4 and full load to the unit.  
Decrease the GAIN pot if there is instability at any  
load point.  
4. Under full load condition, increase the stability  
pot until the unit returns to 60 Hertz (or 50 Hertz  
in 50 Hertz applications).  
This fuse will not remove the + battery input  
power from the PCB when it opens. This means  
the exercise timer will not be reset.  
3.2.5 SET EXERCISE TIME SWITCH  
This switch allows programming the generator to  
start and exercise automatically. See Weekly  
Exercise Cycle.”  
5. Reduce load to 3/4, 1/2, 1/4 and no load.  
Decrease the stability pot if there is instability at  
any load point.  
3.2.6 SYSTEM READY LED  
6. Adjust differential pot to make the recovery to  
load changes even faster and minimize load  
change undershoot and overshoot. If it is set too  
high it may introduce oscillations at some load. It  
can be set to zero (full CCW) if a small amount  
causes oscillations at some load.  
The System Ready LED (green) has two main pro-  
poses. First, the LED will be ON when the  
AUTO/OFF/MANUAL switch is in the AUTO position,  
UTILITY is present, and there are no system alarms.  
This ON state indicates the system is fully ready for  
automatic operation.  
The system ready LED will be OFF when the switch  
is in the MANUAL or OFF positions.  
Figure 3.2 — Engine Governor Adjustment  
The system ready LED is also used to indicate the  
presence of UTILITY sensing at the PCB when the  
switch is either in the AUTO or MANUAL modes. The  
LED will flash at the rate of 1/2 second on, 1/2 sec-  
ond off if the UTILITY sensing level is below the  
transfer back threshold.  
R44  
LED1  
C27  
Q2  
C9  
J2  
C26  
U7  
C4  
D10  
C21  
This secondary function is only available with dip  
switch two in the OFF position (engineered transfer  
switch application).  
C30  
C2  
RL1  
RL2  
R1  
R48  
D17  
3.3 MANUAL TRANSFER AND  
R49  
START-UP  
To transfer electrical loads to the Standby (EMER-  
GENCY) power source side and start the engine man-  
ually, refer to the Owner’s Manual of the particular  
transfer switch.  
U1  
J1  
L3  
D19  
0
DIP SWITCH  
DIFFERENTIAL  
STABILITY  
POSITION 1  
50/60 HZ  
POSITION 2  
GTS/ATS Select  
ON = GTS  
1
3
2
4
UNUSED  
ON = 50 HZ  
GTS/ATS  
OFF = ATS (standard mode)  
OFF = 60 HZ  
50/60 HZ  
®
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Section 3 - Operation  
Guardian 40kW Liquid-cooled Generators  
If DC power to the control board is lost, the weekly  
exercise setting will be lost. This is indicated by all  
five red LEDs continually flashing. In this state the  
generator will still start and run in manual mode, or  
automatically start and run if UTILITY is lost while in  
AUTO mode, but it will not perform a weekly exercise  
cycle.  
3.5 RETRANSFER AND SHUTDOWN  
When utility power source voltage has been restored,  
electrical loads may be transferred back to that  
source and the generator can be shut down as fol-  
lows:  
Verify that utility power supply voltage to the trans-  
fer switch has been positively turned Off, using  
whatever means provided (such as utility main line  
circuit breaker).  
If a failure occurs while running in this mode, the five  
red LEDs will stop flashing, the individual fault LED  
will turn on and the engine will shut down. Once the  
AUTO/OFF/MANUAL switch has been switch to OFF,  
the individual fault LED will turn OFF and the five  
red LEDs will begin flashing to show exercise has still  
not been set.  
• Set the generator’s main circuit breaker to its OFF  
or OPEN position.  
• Let the generator engine run at no-load for a few  
minutes, to stabilize internal unit temperatures.  
• On the generator console, set the AUTO/OFF/  
MANUAL switch to OFF. Wait for engine to come to  
a complete stop.  
Figure 3.2 - “Set Exercise Time” Switch  
For transfer to utility position, refer to the Owner’s  
Manual of the particular transfer switch.  
Turn on the utility power supply to the transfer  
switch, using whatever means provided (such as a  
utility main line circuit breaker). The utility power  
source now powers the loads.  
FUSE  
FUSE  
4A  
BAT.  
CHARGER  
15A  
MAIN  
3.6 AUTOMATIC OPERATION  
To set the system for fully automatic operation, pro-  
ceed as follows:  
AUTO  
OFF  
OFF  
ON  
• Check that load circuits are connected to the  
utility power supply.  
• Set the AUTO/OFF/MANUAL switch to its AUTO  
position.  
• Set the generator main circuit breaker to its ON or  
Closed position.  
SET  
EXERCISE  
TIME  
MANUAL  
3.7 WEEKLY EXERCISE CYCLE  
The engine control board will start and run the gen-  
erator once every seven days for approximately 12  
minutes. If utility should fail during this exercise  
period, the engine control board will transfer the load  
to the generator output and continue to run until util-  
ity returns.  
On the day, and at the time of day chosen for the gen-  
erator to exercise, set the weekly exercise cycle as fol-  
lows:  
1. Place the AUTO/OFF/MANUAL switch in the  
AUTO position.  
2. Press and hold the “Set Exercise” switch for three  
seconds, then release.  
At this time all five red LEDs will flash for approxi-  
mately 10 seconds, then the engine will start and run  
for it’s 12 minute exercise period, then shut down.  
The generator will now start and run each week at the  
same time.  
®
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
4.1 MAINTENANCE PERFORMED BY  
AUTHORIZED SERVICE DEALERS  
4.3 OVERLOAD PROTECTION FOR  
ENGINE DC ELECTRICAL SYSTEM  
Engine cranking, start up and running are controlled  
by a solid state Engine Controller circuit board.  
Battery voltage is delivered to that circuit board via a  
15 amp fuse. These overcurrent protection devices  
will open if the circuit is overloaded.  
A. EVERY THREE MONTHS  
1. Check battery state of charge and condition.  
2. Inspect and test fuel system.  
3. Check transfer switch.  
4. Inspect exhaust system.  
5. Check engine ignition system.  
6. Check fan belts.  
If a circuit breaker opens or a fuse element  
melts, find the cause of the overload before  
resetting the circuit breaker or replacing the  
!
B. ONCE EVERY SIX MONTHS  
1. Test Engine Safety Devices (low oil pressure, low  
coolant level, high coolant temperature).  
fuse.  
4.4 CHECKING FLUID LEVELS  
C. ONCE ANNUALLY  
1. Test engine governor. Adjust or repair, if needed.  
2. Clean, inspect generator.  
4.4.1 CHECK ENGINE OIL  
Check engine crankcase oil level (Figure 4.1) month-  
ly, or prior to use.  
3. Flush cooling system.  
• Remove oil dipstick and wipe dry with a clean,  
lint-free cloth.  
D. FIRST 100 OPERATING HOURS  
• Install oil dipstick, then remove again.  
• Oil should be between FULL and ADD marks.  
• If oil level is below the dipstick ADD mark, remove  
oil fill cap. Add the recommended oil to bring oil  
level up to the FULL mark. DO NOT FILL ABOVE  
THE “FULLMARK. See Section 1.14 for recom-  
mended oils.  
1. Change engine oil and oil filter. (After initial  
change, service engine oil and filter at 150 oper-  
ating hours or 6 months, whichever comes first.)  
2. Retorque cylinder head. (See Torque Specs,  
Section 1.13.)  
3. Retorque intake and exhaust manifold. (See  
Torque Specs, Section 1.13.)  
Figure 4.1 - Oil Dipstick and Oil Fill Cap  
E. EVERY 500 OPERATING HOURS  
1. Service air cleaner.  
2. Check starter.  
Oil Dipstick  
Oil Fill  
3. Check engine DC alternator.  
4.2 COOLING SYSTEM  
Air intake and outlet openings in the generator com-  
partment must be open and unobstructed for contin-  
ued proper operation. This includes such obstruc-  
tions as high grass, weeds, brush, leaves and snow.  
Without sufficient cooling and ventilating air flow, the  
engine/generator quickly overheats, which causes it  
to shut down. (See Section 6 for installation drawings  
and vent locations.)  
Oil Filter  
4.4.2 BATTERY FLUID  
Check battery electrolyte fluid at least once weekly.  
Fluid should cover separators in all battery cells. If  
fluid level is low, add distilled water to cover tops of  
separators. DO NOT USE TAP WATER IN BATTERY.  
The exhaust system parts from this product get  
extremely hot and remain hot after shutdown.  
High grass, weeds, brush, leaves, etc. must  
remain clear of the exhaust. Such materials may  
ignite and burn from the heat of the exhaust  
system.  
4.4.3 ENGINE COOLANT  
Check coolant level in coolant recovery bottle. See  
Specifications, Section 1.10.  
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
• Add recommended coolant mixture as necessary.  
• Periodically remove radiator pressure cap to make  
sure the coolant recovery system is functioning  
properly. Coolant should be at bottom of radiator  
filler neck. If coolant level is low, inspect gasket in  
radiator pressure cap. Replace cap, if necessary.  
To have pressure cap tested, contact an authorized  
service dealer. Inspect cooling system and coolant  
recovery system for leaks.  
4.5.8 CHECK FAN BELT  
• Inspect fan belts every three months. Replace any  
damaged, deteriorated, worn or otherwise defec-  
tive belt.  
• Check fan belt tension. Thumb pressure, exerted  
midway between pulleys, should deflect about 3/8  
to 3/4 inch. Adjust belt tension as required.  
4.5.9 INSPECT ENGINE GOVERNOR  
Visually inspect electronic governor.  
4.5 MAINTENANCE OWNER/  
OPERATOR CAN PERFORM  
DANGER  
4.5.1 CHECK ENGINE OIL LEVEL  
DANGER: Do not attempt to adjust the gover-  
nor. Only qualified service dealers should  
adjust the governor. Excessively high operat-  
Refer to “Checking Fluid Levels” in Section 4.4.  
!
ing speeds are dangerous and increase the  
risk of personal injury. Low speeds impose a  
heavy load on the engine when adequate  
engine power is not available and may short-  
en engine life. Correct rated frequency and  
voltage are supplied only at the proper gov-  
erned speed. Some connected electrical load  
devices may be damaged by incorrect fre-  
quency and/or voltage. Only qualified service  
technicians should adjust the governed speed.  
4.5.2 CHECK BATTERY  
• Check battery fluid level each week as outlined  
under “Check Fluid Levels”.  
• Check battery cables for condition, tightness, cor-  
rosion or damage. Clean, tighten or replace as  
necessary.  
4.5.3 EXERCISE SYSTEM  
If the unit is not set up for automatic operation, start  
the generator engine at least once every seven days  
and let it run at least 12 minutes. See Section 3.6,  
“Weekly Exercise Cycle”.  
4.5.10 CHANGING ENGINE OIL  
Refer to maintenance performed by authorized service  
dealers for engine oil and filter change frequencies.  
4.5.4 INSPECT COOLING SYSTEM  
• Inspect engine cooling system at least once each  
month.  
Drain the oil while the engine is still warm from run-  
ning. This means warm up the engine, shut it down  
and drain immediately as follows:  
• Check hoses for damage, deterioration, leaks, etc.  
Correct any discrepancies found.  
• Check hose clamps for tightness.  
1. Remove OIL DRAIN HOSE from its retaining clip.  
2. Loosen and remove OIL DRAIN HOSE CAP. Drain  
oil completely into suitable container.  
3. When all oil has drained, install and tighten OIL  
DRAIN HOSE CAP, and re-install into its retaining  
clip.  
4.5.5 CHECK ENGINE COOLANT LEVEL  
See “Checking Fluid Levels” in Section 4.4.  
4. Turn OIL FILTER (Figure 4.2) counterclockwise  
4.5.6 PERFORM VISUAL INSPECTION  
and remove. Dispose of old filter.  
5. Apply light coating of new engine oil to seal of new  
oil filter. Install FILTER and tighten by hand only.  
DO NOT OVERTIGHTEN.  
6. Remove OIL FILL CAP. Add recommended oil (see  
SPECIFICATIONS). DO NOT FILL ABOVE THE  
DIPSTICK “FULLMARK. Crankcase oil capacity  
is 4.0 U.S. quarts (3.8 liters).  
Complete a thorough visual inspection of the entire  
engine-generator monthly. Look for obvious damage,  
loose, missing or corroded nuts, bolts and other fas-  
teners. Look for fuel, oil or coolant leaks.  
4.5.7 INSPECT EXHAUST SYSTEM  
Inspect the exhaust system at least once every three  
months. Check all exhaust system pipes, mufflers,  
clamps, etc. for condition, tightness, leaks, security,  
damage.  
After refilling the crankcase with oil, always  
check oil level on dipstick. NEVER OPERATE  
ENGINE WITH OIL BELOW THE DIPSTICK  
!
“ADD” MARK.  
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
7. Start engine and check for oil leaks.  
4.5.13 COOLANT CHANGE  
Every year, have an authorized service dealer drain,  
flush and refill the cooling system. See SPECIFICA-  
TIONS (Section 1.10) for cooling system recommen-  
dations.  
Figure 4.2 - Oil Filter  
4.6 MISCELLANEOUS MAINTENANCE  
4.6.1 CLEANING THE GENERATOR  
Keep the generator as clean and as dry as possible.  
Dirt and moisture that accumulates on internal gen-  
erator windings have an adverse effect on insulation  
resistance.  
Oil Filter  
Periodically clean generator exterior surfaces. A soft  
brush may be used to loosen caked on dirt. Use a  
vacuum system or dry, low pressure air to remove  
any accumulations of dirt. The generator is housed  
inside an all-weather enclosure, clean the enclosure  
with a soft, damp cloth or sponge and water.  
4.5.11 CHANGING THE ENGINE AIR CLEANER  
To replace the engine air cleaner, (part number  
0A4637), remove the air cleaner cover and replace  
the air filter making sure it is positioned properly  
before reattaching the cover.  
Once each year, have the generator cleaned and  
inspected by an authorized service dealer. That deal-  
er will use dry, low pressure air to clean internal  
windings. Parts inside the control console should be  
cleaned and inspected at this time as well.  
See the “Service Schedule,” Section 6, for air cleaner  
maintenance.  
Finally, have the insulation resistance of stator and  
rotor windings checked. If insulation resistances are  
excessively low, the generator may require drying.  
4.5.12 SPARK PLUGS  
Reset the spark plug gap or replace the spark plugs  
as necessary. See Section 6.  
4.6.2 BATTERY  
All lead-acid storage batteries discharge when not in  
use. Refer to specific instructions and warnings that  
accompany the battery. If such information is not  
available, observe the following precautions when  
handling a battery:  
1. Clean the area around the base of the spark plugs  
to keep dirt and debris out of the engine. Clean by  
scraping or washing using a wire brush and com-  
mercial solvent. Do not blast the spark plugs to  
clean.  
2. Remove the spark plugs and check the condition.  
Replace the spark plugs if worn or if reuse is  
questionable. See the “Service Schedule,” Section  
6, for recommended inspection.  
3. Check the spark plug gap using a wire feeler  
gauge. Adjust the gap to 1.01 mm (0.040 inch) by  
carefully bending the ground electrode (Figure  
4.3).  
• DO NOT use jumper cables and a booster battery  
to crank or start the generator engine.  
• DO NOT recharge a weak battery while it is  
installed in the generator. Remove battery from  
generator and recharge in a well-ventilated area,  
away from fuel vapors, sparks, heat or flames.  
• Battery electrolyte fluid is an extremely caustic  
sulfuric solution that can cause severe burns. DO  
NOT permit fluid to contact eyes, skin, clothing,  
painted surfaces, wiring insulation, etc. If any bat-  
tery fluid is spilled, flush the affected area with  
clear water immediately.  
Figure 4.3 – Setting the Spark Plug Gap  
SET PLUG GAP AT 1.01 mm  
(0.040 inch)  
• Always wear safety glasses, rubber apron and  
gloves when handling a battery.  
• Batteries give off explosive hydrogen gas while  
charging. The gas can form an explosive mixture  
around the battery for several hours after charging.  
Any spark, heat or flames can ignite the gas and  
cause an explosion which can shatter the battery,  
causing blindness or other serious injury.  
®
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
4.6.3 BATTERY MAINTENANCE  
4.6.4 BATTERY REPLACEMENT  
The battery should be inspected per the “Service  
Schedule,” Section 6. The following procedure  
should be followed for inspection:  
When replacing batteries, use the same number and  
the type of battery that follows:  
BCI Group No.  
CCA  
1. Inspect the battery posts and cables for tightness  
and corrosion. Tighten and clean as necessary.  
2. Check the battery fluid level of unsealed batteries  
and, if necessary, fill with DISTILLED WATER  
ONLY. DO NOT USE TAP WATER IN BATTERIES.  
3. Have the state of charge and condition checked.  
This should be done with an automotive-type bat-  
tery hydrometer.  
27F  
700 @ 0 deg. F  
NOTE:  
The BCI number should be located directly  
on the battery.  
PERIODIC REPLACEMENT PARTS  
Part Name  
Generac’s Part Number  
DANGER  
Oil Filter  
# 0E7415  
# 046627  
# 0A4637  
Radiator Cap  
Air Cleaner  
Spark Plug  
Storage batteries give off explosive hydrogen  
gas. This gas can form an explosive mixture  
around the battery for several hours after  
charging. The slightest spark can ignite the gas  
and cause an explosion. Such an explosion can  
shatter the battery and cause blindness or  
other injury. Any area that houses a storage  
battery must be properly ventilated. Do not  
allow smoking, open flame, sparks or any spark  
producing tools or equipment near the battery.  
Champion # RC12LC4  
Battery electrolyte fluid is an extremely caustic  
sulfuric acid solution that can cause severe  
!
burns. Do not permit fluid to contact eyes, skin,  
clothing, painted surfaces, etc. Wear protective  
goggles, protective clothing and gloves when  
handling a battery. If the fluid is spilled, flush  
the affected area immediately with clear water.  
Do not use any jumper cables or booster bat-  
tery to crank and start the generator engine. If  
!
the battery has completely discharged, remove  
it from the generator for recharging.  
Be sure the Auto/Off/Manual switch is set to  
the OFF position before connecting the battery  
!
cables. If the switch is set to AUTO or MANUAL,  
the generator can crank and start as soon as  
the battery cables are connected.  
Be sure the utility power supply is turned off,  
or sparking may occur at the battery posts as  
the cables are attached and cause an explosion.  
®
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
4.7 SCHEDULED MAINTENANCE  
Following is a recommended maintenance schedule for Generac small standby and residential generator sets. The  
established intervals in the schedule are the maximum recommended when the unit is used in an average service  
application. They will need to be decreased (performed more frequently) if the unit is used in a severe application.  
Use calendar time from the previous maintenance interval to determine the next required maintenance interval.  
Service Maintenance Interval Information:  
The various service maintenance intervals are designated by interval numbers as follows:  
1 An early inspection of the generator set to ensure it is ready to operate when required and to identify any poten-  
tial problem areas.  
Performed monthly, this inspectin requires approximately .5 man-hours per unit to complete.  
This inspection may be performed by the end user providing the following safety steps are taken to prevent  
the engine from starting automatically without warning:  
To prevent injury, perform the following steps in the order indicated before starting any maintenance:  
Disable the generator set from starting and/or connecting to the load by setting the control panel  
AUTO-OFF-MANUAL switch to the “OFF” position.  
Remove the control panel fuse.  
Turn off the battery charger.  
Remove the negative battery cable.  
The battery charger must be turned off BEFORE removing the battery cable to prevent an over current condi-  
tion from burning out sensitive control panel components and circuits.  
Following all maintenance, reverse these steps to insure the unit is returned to standby setup for normal  
operation when required.  
2 A break-in service inspection of the generator set to ensure it is ready to operate and carry the load when  
required, and to identify any potential problem areas.  
Performed ONLY ONCE following the first three months or the first 30 hours of operation after purchase of  
the unit and requires approximately 2.5 man-hours per unit to complete.  
This inspection contains some maintenance tasks which require special tools, equipment, and/or knowledge  
to accomplish and should be performed only by an authorized service dealer.  
3 An operational inspection of the generator set to ensure it is ready to operate and carry the load when required,  
and to identify any potential problem areas.  
Performed semi-annually or following each 50 hours of operation of the unit and requires approximately 1.5  
man-hours per unit to complete.  
This inspection contains some maintenance tasks which require special tools, equipment, and/or knowledge  
to accomplish and should be performed only by an authorized service dealer.  
4 A mid-level inspection of the generator set to ensure it is ready to operate and carry the load when required,  
and to identify any potential problem areas.  
Performed annually or following each 100 hours of operation of the unit and requires approximately 4.0  
man-hours per unit to complete.  
This inspection contains some maintenance tasks which require special tools, equipment, and/or knowledge  
to accomplish and should be performed only by an authorized service dealer.  
®
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
Maintenance  
Tasks  
Level 1  
Recom-  
mended  
Level 2  
Required  
Level 3  
Required  
Level 4  
Task  
Task  
Task  
Task  
Comp.  
Comp. to be done Comp. to be done Comp.  
Required  
to be done (Date-  
monthly Initials)  
3 months/  
Break-in  
(Date-  
Initials)  
Semi-  
annually  
(Date-  
Initials)  
to be done (Date-  
Annually Initials)  
1. Disable the unit from  
operating per the first page  
warning.  
2. Check the engine oil level.  
Adjust as necessary.  
3. Check the engine coolant  
level. Adjust as necessary.  
4. Check the engine coolant  
thermal protection level.  
Correct as necessary.  
5. Check the natural gas  
delivery system on gas  
engine driven units.  
Tighten connections as  
necessary.  
6. Check the air inlets and  
outlets for debris. Clean as  
necessary.  
7. Check the battery  
electrolyte level if  
accessible. Adjust as  
necessary.  
8. Check the battery posts,  
cables, and charger for  
loose connections,  
corrosion, and proper  
operation. Correct as  
necessary.  
9. Check the unit wiring for  
loose connections,  
corrosion, and damage.  
Correct as necessary.  
10. Check the engine  
accessory drive belts for  
wear, weather cracking,  
and damage. Replace as  
necessary.  
11. Visually inspect the unit  
looking for leaks, wear or  
damage, loose connections  
or components, and  
corrosion. Correct as  
necessary.  
12. Test the engine and  
transfer switch safety  
devices. Correct and/or  
adjust as necessary.  
®
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Section 4 — Maintenance  
Guardian 40kW Liquid-cooled Generators  
Maintenance  
Tasks  
Level 1  
Recom-  
mended  
Level 2  
Required  
Level 3  
Required  
Level 4  
Task  
Task  
Task  
Task  
Comp.  
Comp. to be done Comp. to be done Comp.  
Required  
to be done (Date-  
monthly Initials)  
3 months/  
Break-in  
(Date-  
Initials)  
Semi-  
annually  
(Date-  
Initials)  
to be done (Date-  
Annually Initials)  
13. Initiate an automatic start  
and transfer of the unit to  
site load and exercise it for  
at least 1 hour looking for  
leaks, loose connections  
or components, and  
abnormal operating  
conditions. Correct as  
necessary.  
14. Start and exercise the unit  
at full rated load (use a  
load bank if the site load is  
not enough) for at least 2  
hours looking for leaks,  
loose connections or  
components, and abnormal  
operating conditions.  
Correct as necessary.  
15. Change the engine oil.  
16. Replace the engine oil  
filter(s).  
17. Replace the engine air  
filter(s).  
18. Replace the engine fuel  
filter(s) on diesel engine  
driven units and re-prime  
the fuel system.  
19. Check the engine spark  
plugs on gas engine driven  
units. Clean and re-gap or  
replace as necessary.  
20. Perform a 5 minute no-load  
operational run of the unit  
looking for any post service  
problems.  
21. Return the unit to standby  
setup for operation when  
required.  
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Section 5 — Troubleshooting  
Guardian 40kW Liquid-cooled Generators  
TROUBLESHOOTING POINTS  
PROBLEM  
CAUSE  
CORRECTION  
Engine won’t crank.  
1. 15 amp fuse blown.  
1. Replace fuse.  
2. Loose or corroded or defective  
battery cables.  
2. Tighten, clean or replace  
battery cables as necessary.  
3. Defective starter contactor.  
4. Defective starter motor.  
5. Dead or Defective Battery.  
6. 4 amp fuse blown.  
3. Replace contactor.  
4. Replace starter motor.  
5. Remove, change or replace battery.  
6. Replace fuse.  
Engine cranks, but won't start  
1. Out of fuel.  
2. Fuel solenoid (FS) is defective  
3. Open Wire #14 from Engine Control  
circuit board.  
1. Replenish fuel.  
2. Replace solenoid.  
3. Reconnect wire.  
4. Spark plugs defective.  
4. Clean, regap or replace plugs.  
1. Clean or replace as needed.  
Engine starts hard, runs rough.  
Engine starts, then shuts down.  
1. Flame arrestor (air cleaner) plugged or  
damaged.  
2. Plugged fuel line.  
3. Defective spark plugs.  
2. Unclog fuel line.  
3. Clean, regap or replace plugs.  
1. Engine oil level is low.  
2. Engine is overheated.  
3. Defective Low Oil Pressure Switch  
4. Defective Coolant Temperature Switch  
5. Defective Control Module circuit board.  
6. Coolant Level is Low.  
1. Check oil and add oil as needed.  
2. Check cooling system for leaks.  
3. Replace switch.  
4. Replace switch.  
5. Replace board.  
6. Repair leak - Add coolant.  
7. Replace Switch.  
7. Defective Low Coolant Level Switch  
AUTO/OFF/MANUAL Switch at,  
OFF engine continues to run  
1. Defective AUTO/OFF/MANUAL switch  
1. Replace switch.  
2. Reconnect/close wire.  
2. Open/disconnected wire #15A between  
AUTO/OFF/MANUAL switch and Control  
Module circuit board.  
3. Defective Control Module circuit board  
3. Replace board.  
No AC output from generator.  
1. Check main line circuit breaker.  
2. Check circuit breaker & fuses.  
3. Transfer switch set to NORMAL position  
4. Generator internal failure.  
1. Reset to ON or CLOSED.  
2. Reset and replace, if necessary.  
3. Set to GENERATOR position.  
4. Contact an authorized service dealer.  
5. Thermal circuit breaker open.  
5. Auto-reset - Wait 5 min. and  
attempt restart.  
NOTE:  
Under normal operating conditions, if repair of generator set or replacement of any parts is necessary dur-  
ing the warranty period, you must contact an authorized service dealer. Failure to have the repair or replace-  
ment performed by the authorized service dealer will result in non-coverage of warranty repair cost.  
®
Generac Power Systems, Inc. 23  
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Section 6 - Electrical Data  
Guardian 40kW Liquid-cooled Generators  
Wiring Diagram — Engine — Drawing No. 0E8115-A  
®
24 Generac Power Systems, Inc.  
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Section 6 - Electrical Data  
Guardian 40kW Liquid-cooled Generators  
Wiring Diagram — Engine — Drawing No. 0E8115-A  
®
Generac Power Systems, Inc. 25  
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Section 6 - Electrical Data  
Guardian 40kW Liquid-cooled Generators  
Electrical Schematic — Engine — Drawing No. 0E8116-A  
®
26 Generac Power Systems, Inc.  
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Section 6 - Electrical Data  
Guardian 40kW Liquid-cooled Generators  
Electrical Schematic — Engine — Drawing No. 0E8116-A  
®
Generac Power Systems, Inc. 27  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Mounting Base — Drawing No. 0E8084-A  
®
28 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Mounting Base — Drawing No. 0E8084-A  
ITEM  
PART NO.  
QTY.  
DESCRIPTION  
1
2
3
4
5
6
7
8
9
0E7331  
052860  
052251  
052257  
052252  
052259  
052891  
0536210214  
074906  
047411  
055414  
026850  
022097  
022473  
049813  
0A1694  
025507  
0E7359  
027482  
022129  
045771  
051756  
046526  
022131  
055934M  
049820  
059473  
061902  
058665  
038804D  
038805J  
021991  
036833  
022237  
022131  
075763  
050331  
050331A  
0A4010  
052858  
065852  
045764  
1
4
4
4
4
4
4
1
1
1
1
2
1
1
1
4
3
2
2
1
1
1
1
1
1
2
1
1
REF.  
1
1
1
6
6
WELDMENT MTG BASE 3.9L CRYSLR  
NUT FLANGED HEX M12-1.75  
DAMPENER VIBRATION 40 BLUE  
SPACER .49 X .62 X 1.87 PWDR/ZNC  
DAMPENER VIBRATION  
WASHER FLAT M12  
SCREW HHC M12-1.75 X 80 G8.8  
ASSY WIRE 15.0"  
SCREW HHTT M6-1.0 X 20 BP  
SCREW HHC M6-1.0 X 16 BP  
LUG SLDLSS #2-#8 X 17/64 CU  
WASHER SHAKEPROOF EXT 1/4 STL  
WASHER LOCK M6-1/4  
WASHER FLAT M6-1/4 ZINC  
NUT HEX M6 -1.0 G8 YEL CHR  
1-1/2" BUTTON PLUG  
WASHER SHAKEPROOF EXT 7/16 STL  
ENGINE MOUNT (3.9L CHRYSLER)  
WASHER SHAKEPROOF EXT 5/16 STL  
WASHER LOCK M8-5/16  
NUT HEX M8-1.25 G8 YEL CHR  
SCREW HHC M10-1.5 X 20 G8.8  
WASHER LOCK M10  
WASHER FLAT 3/8-M10 ZINC  
CLAMP VINYL .75 X .343 Z  
NUT HEX LOCK M8-1.25 NY INS  
HOLD DOWN BATTERY  
HOLD DOWN BATTERY  
BATT 12VDC 90-AH 27F  
CABLE BATT RED #4 X 20.00  
CABLE BATT BLK #1 X 30.00  
EARTH STRAP  
SCREW HHC 3/8-16 X 1 G8  
WASHER LOCK 3/8  
10  
11  
12  
13  
14  
15  
16  
18  
19  
20  
21  
22  
23*  
24*  
25*  
26*  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
41  
42  
43  
6
1
1
1
2
2
1
1
WASHER FLAT 3/8 ZINC  
BOOT BATTERY CABLE  
BATTERY POST COVWER (BLACK)  
BATTERY POST COVWER (RED)  
SCREW HHC M8-1.25 X 60 G8.8 FT  
NUT TOP LOCK FL M8-1.25  
SPRING CLIP HOLDER .37-.62  
SCREW HHTT M4-0.7 X 8 BP  
*NOT SHOWN-USED TO HOLD DOWN I/N 32.  
®
Generac Power Systems, Inc. 29  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Enclosure — Drawing No. 0E8439-E  
®
30 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Enclosure — Drawing No. 0E8439-E  
ITEM  
PART NO.  
QTY.  
DESCRIPTION  
1
2
3
4
5
6
7
8
9
0E8411  
0E8042  
0E8041  
0C2454  
0E7807  
0E7808  
0E7809  
0E8387  
0E6986  
0E7795  
089961  
0A2115  
0E8404  
0D2538A  
0D2538  
043116  
022097  
022473  
0E7570  
0E7571  
070015  
0E7662  
0D2537A  
0D2537  
0D2023  
0E7869  
0E8001  
0E8060  
0E7966  
0D3037A  
0C7781  
0E7794  
0E8052  
0D3037  
0E8007  
0E8008  
0E7992  
0E8055  
026850  
0912970063  
0912970064  
049813  
0E8665  
0D2023  
0E8442  
0E7829A  
0E7829B  
0E7829P  
0E7829R  
0E7829S  
0E7829T  
0E7829N  
078115  
1
1
1
62  
1
1
1
1
2
1
2
4
1
1
1
8
12  
12  
2
4
4
4
1
1
2
2
1
1
1
1
2
1
1
1
1
1
1
1
4
2
2
2
1
1
1
1
2
4
2
1
1
2
8
INTAKE DUCT HSB  
DUCT DISCHARGE RH FRONT  
DUCT DISCHARGE LH FRONT  
SCREW TH-FRM M6-1 X 16 N WA Z/JS  
BAFFLE REAR BOTTOM  
POST CORNER LH REAR  
POST CORNER RH REAR  
BAFFLE REAR TOP  
DOOR COMPARTMENT SIDE  
SUPPORT, R/H SIDE  
FOAM STRIP 3/4" WIDE X 3/16" THK (40" LG)  
WASHER NYLON .257  
BRACKET STIFFENER LH FRONT  
HINGE LIFT OFF TYPE B KNUCKLE  
HINGE LIFT OFF TYPE B PIN  
SCREW HHC M6-1.0 X 12 G8.8  
WASHER LOCK M6-1/4  
WASHER FLAT 1/4-M6 ZINC  
GAS SPRING  
BALL STUD GAS SPRING MOUNT  
NUT HEX 5/16-18 LOCK  
SCREW WING M6-1.00 X 25  
HINGE LIFT OFF TYPE A KNUCKLE  
HINGE LIFT OFF TYPE A PIN  
TRIM VINYL SELF GRIPPING (91" LG)  
BRACKET STIFFENING BACK  
MUFFLER BOX  
ROOF W/GAS SPRING MNT 3.0L FRD  
BRACE FRONT TOP  
LATCH 1/4 TURN NONLOCKING  
PAWL DOOR HSB  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
41  
42  
43  
44  
50 *  
51  
52  
53  
54  
55  
56  
57  
58  
SUPPORT LH SIDE  
MUFFLER BOX TOP  
LATCH QUARTER TURN LOCKING  
POST CORNER LH FRONT  
POST CORNER RH FRONT  
BRACE FRONT BOTTOM  
DUCT DISCHARGE MID FRONT  
WASHER SHAKEPROOF EXT 1/4 STL  
ASSY GRD WIRE 99HSB  
ASSEMBLY BASE-DOOR GROUND WIRE  
NUT HEX M6 X 1.0 G8 YEL CHR  
BRACKET STIFFENER LH FRONT  
TRIM VINYL SELF GRIPPING (165.5"LG)  
KIT INSULATION 3.9L HSB  
AI ROOF PANEL 1  
AI DOOR PANEL  
AI CORNER POST PANEL 1  
AI CORNER POST PANEL 2  
AI SUPPORT LH PANEL  
AI SUPPORT RH PANEL  
AI ROOF PANEL 2  
WASHER SELF LOCKING DOME  
* ALL ITEMS NOTATED WITH "AI" ARE COMPONENTS OF 0E8442  
®
Generac Power Systems, Inc. 31  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Control Panel — Drawing No. 0E7118-G  
®
32 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Control Panel — Drawing No. 0E7118-G  
ITEM PART NO. QTY.  
DESCRIPTION  
ITEM PART NO. QTY.  
DESCRIPTION  
1
2
3
4
5
6
7
8
9
10  
11  
12  
13  
14  
15  
16  
0E7195  
0E7196  
0E7197  
0E7193  
0E7194  
0E4494  
082573  
032300  
022676  
067682B  
060015  
054199  
0C2657  
099076  
040213  
0E9668  
0E4905  
1
1
1
1
1
1
1
2
1
1
1
1
1
1
2
1
1
CONTROL BOX HSB  
34  
35  
36  
0D4698 *  
0E7252  
0C1229  
REF.  
1
1
BLOCK TERM 20A 6 X 3 X 1100V  
BRACKET CB 221.5 X 102  
DECAL WARNING ELECTRICAL  
SHOCK  
DECAL AVR COVER  
COVER PLATE, AVR  
HARNESS CNTRL PNL 3.0L FORD  
(NOT SHOWN)  
SCREW PPPH HI-LO #4-24 X 3/8  
SCREW HHTT M5-0.8 X 10 BP  
CONN DEUTSCH GASKET 8/12 POS  
DT  
SCREW PHTT #6-32 X 3/8 ZYC  
SCREW PHTT #6-32 X 5/8 ZYC  
WASHER LOCK #6  
SCREW PHTT M4-0.7 X 12 ZYC  
WASHER LOCK #8-M4  
SCREW PPHM M5-0.8 X 30 ZINC  
SCREW HHTT M5-0.8 X 16  
WASHER LOCK #10  
WASHER FLAT #10 ZINC  
NUT HEX M5-0.8 G8 YEL CHR  
SCREW HHTT M6-1.0 X 12 ZINC  
SCREW HHC M6-1.0 X 20 G8.8  
WASHER LOCK M6-1/4  
WASHER FLAT 1/4-M6 ZINC  
WIRE ASSY 3" X (2) 3/16" TABS  
WASHER MICA .203  
WASHER SHAKEPROOF EXT #10  
STL  
COVER FRONT PANEL HSB  
COVER TOP PANEL HSB  
DECAL WARNINGS HSB  
DECAL CONTROLS HSB  
SWITCH ROC DPDT ON-OFF-ON  
SWITCH ROCKER DPST 125V SPD  
HOLDER FUSE  
37  
38  
39  
0C1127  
0A1441B  
0E7128  
1
1
1
FUSE 15A X AGC15  
40  
41  
42  
0E7358  
074908  
0C5141  
8
6
1
FUSE 4A SLO BLO GLASS  
FITTING CONDUIT 90D 3/8"  
DECAL DANGER HIGH VOLTAGE  
TRANSFRMR 16V 6VA  
TRANSFORMER 16V 56VA  
PCB SUPPORT SNAP-IN 1/4"  
ASSY PCB HSB CONTROLLER 3.9L  
ASSY PCB HSB CONTRLR 3.0L  
FORD  
ASSY VOLTAGE REGULATOR 60HZ  
RELAY 12VDC C FORM W/DIODE  
SOCKET RELAY  
CONN DEUTSCH RECEPT GY/FLN  
CONN DEUTSCH RECEPT WDGE  
BLKHD  
ASSY BOSCH GOV DRIVER  
CIRCT BRK 5.5 X 1 ETA 46-500-P  
ASSY 2A 12V UL BATTERY  
CHARGER  
FITTING CONDUIT STR 1-1/2"  
DECAL NEUTRAL  
DECALCUSTOMER CNNCTN XFER  
SW  
BLOCK TERM 20A 6 X 6 X 1100V  
DECAL CUSTOMER CNNCTN E1 E3  
N
43  
44  
45  
46  
47  
49  
50  
51  
52  
53  
54  
55  
56  
57  
58  
59  
60  
0C2699  
0C2323  
022155  
0C2265  
022264  
020911  
066849  
022152  
023897  
051716  
090388  
042568  
022097  
022473  
0441140187  
070370  
023762  
11  
4
15  
4
4
2
2
4
3
2
2
4
8
6
2
2
1
17  
18  
19  
20  
21  
067680  
1
1
REF.  
REF.  
REF.  
0E6875A  
0E6881 *  
0C5139 *  
0E5142 *  
22  
23  
24  
0E3161  
054450  
0D5070A  
1
1
1
25  
26  
27  
0E2514  
0A9457  
0E7539  
1
1
1
61  
62  
63  
64  
65  
66  
67  
68  
055444  
030468  
049939  
022158  
022985  
038750  
0A2115  
0C2454  
1
1
1
1
1
2
4
4
HEATSINK  
WASHER STEP NYLON .20  
RECTIFIER MSC 12A 600V 1N1206R  
NUT HEX #10-32 STEEL  
WASHER FLAT #6 ZINC  
SCREW HHC M6-1.0 X 30 G8.8  
WASHER NYLON .257  
28  
29  
046357 *  
0D3719B  
REF.  
1
30  
31  
057073  
0E7283  
0E3628  
0E3664  
0E7539A  
1
1
1
1
1
JUNCTION BLOCK 3/8-16  
CB 0150A2P240V S QN2 LL  
CB 0200A2P240V S QN2 LL  
BASE QN CIRCUIT BREAKER  
DECAL TB1 HSB CONTROL PANEL  
SCREW THF M6-1 X 16 N WA Z/JS  
32  
33  
* ITEMS INCLUDED AS PART OF I/N 39  
®
Generac Power Systems, Inc. 33  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Engine — Drawing No. 0E8121-D  
®
34 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Engine — Drawing No. 0E8121-D  
ITEM PART NO. QTY.  
DESCRIPTION  
ITEM PART NO. QTY.  
DESCRIPTION  
1
2
0E5048A  
0E7477  
1
1
FLEXPLATE 3.9L HSB  
MACHINING, 3.9L ENGINE  
ADAPTOR  
39  
40  
050873A  
031919  
1
1
PLUG PIPE 1/4 CSK W/ VIBRA SL  
PLUG STD PIPE 3/8 COUNTER-  
SUNK  
3
4
5
6
0E6703  
0E8336  
0E7841  
0E7254  
1
REF  
2
COVER, FLYWHEEL ACCESS  
REWORK, 3.9L CHRYSLER ENGINE  
GASKET, THERMOSTAT ADAPTOR  
MACH, THERM ADAPTOR 3.9L  
CHRY  
BRACKET, IGNITION COIL  
COIL IGNITION 3.9L CHRYSLER  
SCREW HHC M6-1.0 X 16 G8.8  
BOLT, AUTO TRANS CRANKSHAFT  
BRACKET, ALTERNATOR  
FAN SPACER, ENGINE COOLING  
WASHER LOCK M6-1/4  
WASHER FLAT 1/4-M6 ZINC  
SCREW HHC M6-1.0 X 35 G8.8 BLK  
NUT HEX M6 X 1.0 G8 YEL CHR  
SCREW HHC 3/8-16 X 1 G8  
WASHER FLAT 3/8-M10 ZINC  
WASHER LOCK 3/8  
41  
42  
43  
44  
45  
46  
47  
48  
49  
50  
51  
52  
53  
54  
55  
56  
57  
58  
59  
60  
61  
62  
63  
64  
65  
66  
67  
022145  
030795  
051756  
046526  
0A1232A  
0A7801B  
045772  
022403  
0E7950  
0E7951  
0E8445  
0E7415  
042568  
061652  
031578  
082120  
023645  
0E9974  
0D3488A  
0E7954  
0E8309  
029187  
032712  
054455  
0E8606  
0E8642  
0E8597  
6
6
5
6
1
1
1
2
1
1
1
1
1
1
1
1
5
2
1
1
1
2
2
1
2
WASHER FLAT 5/16-M8 ZINC  
SCREW HHC 5/16-18 X 1 G5  
SCREW HHC M10-1.5 X 20 G8.8  
WASHER LOCK M10  
ASSEMBLY, D.C. ALTERNATOR  
PULLEY POLY-V 82 OD.  
NUT HEX M10-1.5 G8 YEL CHR  
SCREW HHC 5/16-18 X 2 G5  
TUBE, DIPSTICK 3.9L CHRYSLER  
DIPSTICK OIL LEVEL 3.9L CRYSLR  
BRACKET, DIPSTICK TUBE  
OIL FILTER, 3.9L CHRYSLER  
SCREW HHC M6-1.0 X 20 G8.8  
SCREW HHC M10-1.5 X 85 G8.8  
SCREW HHC 3/8-16 X 1-1/2 G8  
SPACER .41 X .75 X .39 ST/ZNC  
SCREW SHC 3/8-16 X 1.25 G8.8 Z  
CAP VINYL 3/8"ID X 1"DP BLK  
BELT SERPENTINE 70"  
CABLE IGN COIL 3.9L CHRYSLER  
ASSY, IGNITION MODULE 3.9L  
SPACER .19 X .31 X .50 PL  
SCREW HHTT #10-32 X 1.75 CZ  
ADP OIL DRN 1/2-20  
SCREW PPH TAPPING #4 X 3/8"LG  
ASSEMBLY, RESISTOR  
HARNESS, 3.9L CHRYSLER ENGINE  
(NOT SHOWN)  
1
7
8
9
0E7956  
0E7953  
047411  
0E8591  
0E7921  
0E7749  
022097  
022473  
049721  
049813  
036833  
022131  
022237  
0E9747  
022129  
049821  
057073  
052677  
066849  
056739  
0D2244M  
087599  
0E0992B  
1
1
4
6
1
1
7
10  
2
3
11  
21  
14  
1
11  
3
1
1
2
1
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
STARTER, 12 VOLT  
WASHER LOCK M8-5/16  
SCREW SHC M8-1.25 X 30 G12.9  
JUNCTION BLOCK 3/8-16  
WASHER NYLON .50 X .87 X .06  
SCREW HHTT M5-0.8 X 16  
RELAY SOLENOID 12VDC PNL MNT  
ASSY MAGPICKUP(3/8-24 MALE)  
PLUG PLASTIC 3/8 NPT  
1
1
REF  
REF  
1
PLUG EXPANSION 21/32" O.D.  
(WATER PUMP) (QTY 1)  
68  
0E8755  
1
HARNESS, IGNITION 3.9L CHRY  
(NOT SHOWN)  
PLATE, FLEX DISK SPACER  
SCREW SHC M10-1.5 X 25 G12.9  
CAP VINYL 1/4"ID X 1"DP BLK  
HEAT SHEILD, L/H SIDE  
SCREW THF M6-1X16 N WA Z/JS  
BARBED EL 90 3/8 NPT X 3/8  
HOSE OIL DRAIN ASSY 21"  
HOSE CLAMP BAND 5/8"  
30  
0E0992A  
REF  
PLUG EXPANSION 14.1 O.D.  
(INJCTOR HOLE) (QTY 6)  
COOLING FAN 10-BLADE (KYSAIR)  
CLUTCH, COOLING FAN  
TENSIONER W/BRACKET  
PULLEY CRANKSHAFT 3.9L  
CRYSLR  
ASSY,WATER LEVEL SENSOR C/E  
PL  
SENSOR HI COOLANT SHUTDOWN  
PLUG STD PIPE 1/8 SOCKET HEAD  
SWITCH,OIL PRESSURE, 10PSI,  
2POL  
69  
70  
71  
72  
73  
74  
75  
76  
77  
0E8731  
052647  
0E9975  
0F1444A  
0C2454  
043790  
069860C  
048031J  
0F1444  
1
2
1
2
2
1
1
REF  
1
31  
32  
33  
34  
0E7754  
0E7854  
0E7855  
0E7952  
1
1
1
1
35  
0E0561  
1
36  
37  
38  
035606  
061012  
0A8584  
1
1
1
HEAT SHIELD, R/H SIDE  
®
Generac Power Systems, Inc. 35  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Radiator — Drawing No. 0E8102-E  
®
36 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Radiator — Drawing No. 0E8102-E  
ITEM  
PART NO.  
QTY.  
DESCRIPTION  
1
2
3
4
5
6
7
8
9
10  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
0D7825A  
0D7174C  
0E7640  
0E7924  
0F2853  
0D8252  
0D8251  
0E0726  
076749  
035685  
069860C  
058443  
0C2454  
052250  
048031C  
029032  
0A2111  
0E7640A  
035461  
065852  
051756  
022131  
046526  
045772  
1
1
1
1
1
1
1
1
1
4
1
17  
5
2
1
1
1
1
1
1
4
8
4
4
RADIATOR COPPER BRASS  
VENTURI,3.9L CRYSLR HSB 22"FAN  
RADIATOR SUPPORT L/H SIDE  
HOSE LOWER RADIATOR  
HOSE, RADIATOR UPPER, 3.9L  
FAN GUARD, TOP  
FAN GUARD, BOTTOM  
BRACKET, WATER BOTTLE 1.5L MIT  
TANK COOLANT RECOVERY  
CLAMP HOSE #28 1.32-2.25  
HOSE OIL DRAIN ASSY 21"  
SCREW CRIMPTITE 1/4-20 X 5/8  
SCREW TH-FRM M6-1X16 N WA Z/JS  
TAPE FOAM 1 X 1 (27"LG)  
CLAMP HOSE BAND 1/4  
HOSE 9/32 ID (30" LG)  
SCREW SWAGE 10-32 X 5/16 Z/YC  
RADIATOR SUPPORT R/H SIDE  
BARBED STR 1/4NPT X 3/8  
SPRING CLIP HOLDER .37-.62  
SCREW HHC M10-1.5 X 20 G8.8  
WASHER FLAT 3/8-M10 ZINC  
WASHER LOCK M10  
NUT HEX M10-1.5 G8 YEL CHR  
®
Generac Power Systems, Inc. 37  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Fuel System — Drawing No. 0E8122-F  
®
38 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Fuel System — Drawing No. 0E8122-F  
ITEM  
PART NO.  
QTY.  
DESCRIPTION  
1
2
3
4
5
6
7
8
9
033212  
075580  
0E8365  
039253  
022145  
022129  
045771  
042907  
0C2454  
026307  
0E1056  
0E6584  
057822  
059194  
064945  
0D1509  
050279  
0E7839  
0E6586  
0E4394  
040105  
0E6382B  
0F2119  
0E6376B  
042561  
057822  
0E7929  
0A4637  
0E6406  
0E7702  
0A4632A  
037561  
046580  
0E8286  
044118  
049815  
049226  
051713  
022097  
057796  
057795A  
052223  
061012  
0E9295  
0F3994  
4
1
1
2
2
8
2
2
2
1
1
1
3
1
1
1
1
1
2
1
1
1
2
1
2
1
1
1
1
1
1
1
4
1
1
4
4
4
4
1
1
1
1
1
1
SCREW HHC 5/16-18 X 1-1/4 G5  
FLANGE FUEL INLET  
ASSY REG. 3.9L N/G-LPV 1800RPM  
SCREW HHC M8-1.25 X 20 G8.8  
WASHER FLAT 5/16 ZINC  
WASHER LOCK M8-5/16  
NUT HEX M8-1.25 G8 YEL CHR  
SCREW HHC M8-1.25 X 16 G8.8  
SCREW TH-FRM M6-1 X 16 N WA Z/JS  
ELBOW 90D STREET 3/4  
FUEL HOSE ASSY NAT.GAS/L.P.V.  
BRACKET REGULATOR 3.0L FORD HSB  
CLAMP HOSE #8 .53-1.00  
HOSE 5/8 ID LPG & NG (36" LG)  
GASKET CARB ADAPTOR  
DECAL INLET PRESSURE  
DECAL FUEL INLET NG  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
41  
42  
43  
44  
45  
MACHINING, CARBURETOR ADAPTOR  
GASKET BOSCH 32 & 40  
ACTUATOR BOSCH 40 GOVERNOR  
HOSE COOL 2IN ID 20R4 (2" LG)  
VENTURI HOLDER W/40MM ACTUATOR  
O-RING 45.63 ID X 2.62 WIDTH  
VENTURI 28 ID THROTTLE W/CHOK  
CLAMP HOSE #36 1.88-2.75  
CLAMP HOSE #8 .53-1.00  
BASE AIR CLEANER PLATE  
FILTER AIR 11.5" CA326  
HOLDER VENTURI  
HOLD DOWN AIR CLEANER  
PLATE AIR CLEANER TOP  
NUT WING 1/4-20 NYLK  
SCREW SHC M6-1.0 X 45 G12.9  
STREET EL 45DEG 1/2" NPT BRASS  
BARBED STR 1/2NPT X 5/8  
SCREW HHC M5-0.8 X 16 G8.8  
WASHER LOCK M5  
WASHER FLAT M5  
WASHER LOCK M6-1/4  
GROMMET  
BARBED EL 90 3/4 PLASTIC  
HOSE 1/2 ID SAE-30R2 FUEL/OIL  
PLUG STD PIPE 1/8 SOCKET HEAD  
ASSY THROTTLE 28MM  
PCV VALVE 2.5L FORD  
®
Generac Power Systems, Inc. 39  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Alternator — Drawing No. 0E5146-B  
®
40 Generac Power Systems, Inc.  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Alternator — Drawing No. 0E5146-B  
ITEM  
PART NO.  
QTY.  
DESCRIPTION  
1
2
0E5093A  
0E7413A  
0E5094A  
0E7412A  
0E5706  
0E5048  
0E5048A  
0E6668  
0E6076  
046526  
1
1
1
1
1
REF  
REF  
1
1
8
ROTOR 390 30KW 1P DIRECT HSB  
ROTOR 390 40KW 1P DIRECT HSB  
STR-390--35AD1 HSB (382MM LONG)(3.0LFORD)  
STR-390--40AD HSB (433MM LONG)(3.9L CHRYSLER)  
REAR BEARING CARRIER 390/DRCT  
FLEXPLATE 3.0L FORD  
3
4
FLEXPLATE 3.9L HSB  
5
6
7
8
9
FLYWHEEL ASSY 3.0L HSB LG GEAR  
REVCOR FAN 10.75 X 2 W/PRESS DIS  
WASHER LOCK M10  
SCREW HHC M10-1.5 X 16 G8.8  
STUD M14-2.0 X 490 G5 ZINC (3.0L FORD)  
STUD M14-2.0 X 540 G5 ZINC (3.9L CHRYSLER)  
WASHER LOCK M14  
051755  
4
4
4
4
04576100BK  
04576100BF  
043123  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
051779  
0E7587  
023365  
092980  
052625  
0A2602  
042558  
0A2601  
0E7226  
045757  
4
1
5
4
4
1
1
1
1
2
2
4
4
1
NUT HEX M14-2.0 G8 YEL CHR  
ASSY BRUSH HOLDER 390/HSB  
WASHER SHAKEPROOF INT #8  
SCREW PPHM M4-0.7 X 25  
SCREW SHC M10-1.5 X 35 G12.9  
WASHER FLAT .688 ID X 3.25 OD  
KEY SQ 3/8 X 1 STEEL  
SCREW HHC M16-2.0 X 45 G8.8  
GUARD STATOR 390  
SCREW HHC M6-1.0 X 25 G8.8  
NUT TOP LOCK FL M6-1.0  
052857  
051715  
038150  
077043F  
NUT HEX M4-0.7 G8 YEL CHR  
WASHER FLAT #8 ZINC  
CONDUIT FLEX 1-1/4" (30" LG)  
ROTOR REPLACEMENT PARTS  
30  
31  
047248  
070892  
1
1
BALL BEARING-45 MM  
SLIP RING -MACHINED-  
®
Generac Power Systems, Inc. 41  
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Section 7 - Exploded Views and Parts  
Guardian 40kW Liquid-cooled Generators  
Muffler — Drawing No. 0E8068-E  
7
21  
13  
12  
11  
10  
5
1
22  
10  
11  
10  
12  
23  
13  
14  
17  
19  
22  
TO  
COMPARTMENT  
9
TO EXHAUST  
MANIFOLD  
21  
10  
16  
19  
15  
6
20  
3
11  
14  
20  
11  
17  
24  
8
TO EXHAUST  
MANIFOLD  
19  
2
20  
8
19  
11  
8
15  
4
18  
ITEM PART NO. QTY.  
DESCRIPTION  
ITEM PART NO. QTY.  
DESCRIPTION  
1
0E8616  
1
MUFFLER 7" X 9" X 21" 2.5" IN &  
OUT  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25*  
052860  
052891  
0E8816  
051769  
0E0170  
049808  
024114  
080762  
0E8726  
039288  
0F0170A  
082361  
4
4
2
4
1
8
6
2
2
NUT TOP LOCK FL M12-1.75  
SCREW HHC M12-1.75 X 80 G8.8  
EXHAUST FLANGE 2" PIPE  
WASHER LOCK M12  
EXHAUST BLANKET 705MM  
WASHER FLAT M12  
NUT HEX 5/16-24 STEEL  
BOLT U 3/8-16 X 2.62  
STRAP MUFFLER  
2
3
4
5
0F1081  
0F1087  
0E8026  
0E5914  
1
1
1
1
WYE, PIPE 3.9L CHRYSLER  
PIPE R/H SIDE 3.9L CHRYSLER  
PIPE L/H EXHAUST MANIFOLD  
BRACKET MUFFLER 3.0L FORD  
HSB  
6
7
8
0E8702  
0E8727  
036797  
039253  
022145  
022129  
045771  
0C2454  
1
1
3
2
6
9
3
4
PIPE MUFFLER INLET  
PIPE MUFFLER OUT  
BOLT U 5/16-18 X 2.25  
SCREW HHC M8-1.25 X 20 G8.8  
WASHER FLAT 5/16-M8 ZINC  
WASHER LOCK M8-5/16  
NUT HEX M8-1.25 G8 YEL CHR  
SCREW TH-FRM M6-1 X 16 N WA  
Z/JS  
1
1
REF  
SCREW HHC M8-1.25 X 55 G8.8  
EXHAUST BLANKET 875MM  
INSULATION-EXAUST (3.33" LG)  
9
10  
11  
12  
13  
*NOT SHOWN-USED FOR ITEM #2  
®
42 Generac Power Systems, Inc.  
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Section 8 — Installation Diagram  
Guardian 40kW Liquid-cooled Generators  
Installation Diagram — Drawing No. 0E8422-A  
®
Generac Power Systems, Inc. 43  
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Section 9 - Notes  
Guardian 40kW Liquid-cooled Generators  
®
44 Generac Power Systems, Inc.  
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Section 9 - Notes  
Guardian 40kW Liquid-cooled Generators  
®
Generac Power Systems, Inc. 45  
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Section 10 – Warranty  
Guardian 40kW Liquid-cooled Generators  
GENERAC POWER SYSTEMS "TWO YEAR" LIMITED WARRANTY FOR GUARDIAN®  
"PREPACKAGED EMERGENCY AUTOMATIC STANDBY GENERATORS"  
For a period of two years from the date of original sale, Generac Power Systems, Inc. (Generac) warrants that its Guardian generator  
will be free from defects in material and workmanship for the items and period set forth below. Generac will, at its option, repair or  
replace any part which, upon examination, inspection and testing by Generac or a Guardian Authorized Warranty Service Dealer, is  
found to be defective. Any equipment that the purchaser/owner claims to be defective must be examined by the nearest Guardian  
Authorized Warranty Service Dealer. All transportation costs under the warranty, including return to the factory, are to be borne and  
prepaid by the purchaser/owner. This warranty applies only to Generac Guardian prepackaged emergency automatic standby genera-  
tors sold and rated for use in "Standby" applications.  
WARRANTY SCHEDULE  
YEARS ONE and TWO - 100% (one hundred percent) transferable coverage on Labor and Part(s) listed (proof of purchase and main-  
tenance is required):  
Engine - All Components  
Alternator - All Components  
Transfer System - All Components  
Steel enclosures are warranted against rusting for the first year of ownership only. Damage caused after receipt of generator is the  
responsibility of the owner and is not covered by this warranty. Nicks, scrapes, dents or scratches to the painted enclosure should be  
repaired promptly by the owner.  
All warranty expense allowances are subject to the conditions defined in Guardian's Warranty Policies, Procedures and Flat Rate  
Manual.  
THIS WARRANTY SHALL NOT APPLY TO THE FOLLOWING:  
• Guardian generators that utilize non-Guardian/Generac replacement parts.  
• Guardian generators utilizing non-Guardian/Generac automatic transfer switches.  
• Repairs performed by individuals other than Guardian/Generac authorized dealers.  
• Any Guardian generators used as rental or trailer mounted applications.  
• Air-cooled units used for prime power in place of existing utility power where utility power is present or in place of utility power where  
utility power service does not normally exist.  
• Costs of normal maintenance, adjustments, installation and start-up.  
• Steel enclosures that are rusting due to the improper installation, location in a harsh or saltwater environment or scratched where  
integrity of paint applied is compromised.  
• Failures caused by any contaminated fuels, oils, coolants or lack of proper fluid amounts.  
• Failures due, but not limited, to normal wear and tear, accident, misuse, abuse, negligence or improper installation. As with all  
mechanical devices, the Generac engines need periodic part(s) service and replacement to perform well. This warranty will not  
cover repair when normal use has exhausted the life of a part(s) or engine.  
• Failures caused by any external cause or act of God, such as collision, theft, vandalism, riot or wars, nuclear holocaust, fire,  
freezing, lightning, earthquake, windstorm, hail, volcanic eruption, water or flood, tornado or hurricane.  
• Damage related to rodent and/or insect infestation.  
• Products that are modified or altered in a manner not authorized by Generac in writing.  
• Any incidental, consequential or indirect damages caused by defects in materials or workmanship, or any delay in repair or replace-  
ment of the defective part(s).  
• Failure due to misapplication.  
Telephone, cellular phone, facsimile, internet access or other communication expenses.  
• Living or travel expenses of person(s) performing service, except as specifically included within the terms of a specific unit warranty  
period.  
• Expenses related to "customer instruction" or troubleshooting where no manufacturing defect is found.  
• Rental equipment used while warranty repairs are being performed.  
• Costs incurred for equipment used for removal and/or reinstallation of generator, (i.e.; cranes, hoists, lifts, etc.)  
• Overnight freight costs for replacement part(s).  
• Overtime labor.  
• Starting batteries, fuses, light bulbs and engine fluids.  
THIS WARRANTY IS IN PLACE OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED. SPECIFICALLY, GENERAC MAKES  
NO OTHER WARRANTIES AS TO THE MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states do not  
allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you.  
GENERAC'S ONLY LIABILITY SHALL BE THE REPAIR OR REPLACEMENT OF PART(S) AS STATED ABOVE. IN NO EVENT  
SHALL GENERAC BE LIABLE FOR ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF SUCH DAMAGES ARE A  
DIRECT RESULT OF GENERAC'S NEGLIGENCE. Some states do not allow the exclusion or limitation of incidental or consequential  
damages, so the above limitation may not apply to you.  
This warranty gives you specific legal rights. You also have other rights from state to state.  
®
GENERAC POWER SYSTEMS, INC.  
P.O. BOX 297 • WHITEWATER, WI 53190  
Revision (10/01/04)  
Part No. 0E8359  
Revision F (01/24/05)  
Printed in U.S.A.  
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