Generac Power Systems GN - 320 User manual

Manual No. A8927
Revision 0 (11/16/98) Printed in U.S.A.
GENERAC®ENGINES
Overhead Valve
Industrial
Owner’s Manual
Model No. GN - 320/360/410 (11/13/15 Horsepower)
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If you don’t understand any portion of this manual, contact
Generac for a demonstration of actual starting, operating and
servicing procedures.
Throughout this publication and on tags and decals affixed to
the generator, DANGER, WARNING and CAUTION blocks are
used to alert you to special instruction about a particular
operation that may be hazardous if performed incorrectly or
carelessly. Observe them carefully.
These safety warnings cannot eliminate the hazards that they
indicate. Strict compliance with the special instructions while
performing the service plus “common sense” are major
measures to prevent accidents.
The following definitions apply to DANGER,WARNING,
CAUTION and NOTE blocks found throughout the manual.
These safety symbols indicate the following:
DANGER: After this heading you can read handling,
installing, operating or servicing instructions that, if not
strictly complied with, will result in personal injury.
WARNING: After this heading you can read handling,
installing, operating or servicing instructions that, if not
strictly complied with, may result in personal injury.
CAUTION: After this heading you can read instructions for
handling, installing, operating or servicing the generator
that, if not strictly complied with, may result in damage to
equipment and/or property.
NOTE: After this heading you can read explanatory statements that
require special emphasis.
These symbols indicate the following:
Points out important safety information and, if not followed, could
endanger personal safety and/or property of yourself and others.
P otential explosion hazard.
Potential fire hazard.
Potential electrical shock hazard.
RULES FOR SAFE OPERATION
Study these RULES FOR SAFE OPERATION carefully before
operating or servicing this equipment. Become familiar with the
OWNER’S MANUAL and with the engine.The engine can
operate safely, efficiently and reliably only if it is properly
operated and maintained. Many accidents are caused by failing
to follow simple and fundamental rules or precautions.
Generac cannot possibly anticipate every possible circumstance
that might involve a hazard. The warnings in this manual and on
tags and decals affixed to the equipment, are therefore, not all-
inclusive. If you use a procedure, work method or operating
technique Generac does not specifically recommend, you must
satisfy yourself that it is safe for you and others.You must also
make sure the procedure, work method or operating technique
that you choose does not render the engine to be unsafe.
DANGER: Do not tamper with the engine governed speed.
High operating speeds are dangerous and increase the
risk of personal injury or damage to the equipment.
Operating at low speeds with heavy load may shorten the
engine’s life.
BEFORE OPERATING
• Gasoline is highly FLAMMABLE and its vapors are
EXPLOSIVE. Do not permit smoking, open flames, sparks or
heat in the area while handling gasoline. Avoid spilling
gasoline on a hot engine. Comply with all of the laws
regulating storage and handling of gasoline.
• Store gasoline and other fuels only in containers designed
and approved for the storage of such materials.
• Pressure can build up in the fuel tank. Loosen the fuel tank
slowly to relieve any pressure in the tank.
• Add gasoline and other fuels in a clean, well-ventilated area.
Wipe up any spilled gasoline immediately. If gasoline has
been spilled, let it dry completely before starting the engine.
The engine exhaust from this product
contains chemicals known to the State
of California to cause cancer, birth
defects, or other reproductive harm.
WWAARRNNIINNGG::

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• Do not overfill the fuel tank. Always allow room for fuel
expansion. If the tank is overfilled, the fuel can overflow onto
a hot engine and cause a FIRE or an EXPLOSION.
• Allow at least two (2) feet of clearance on all sides of the
engine, even while operating it outdoors, or you could damage
the engine.
• Thoroughly inspect the engine for loose or damaged parts
before each use. Do not use the engine until adjustments or
repairs are made.
• Check the oil level in the engine before each use.
• Inspect the engine periodically. Repair or replace all damaged
or defective parts immediately.
• Inspect fuel system frequently for leaks or damage. Repair or
replace any damaged or leaking component immediately.
Never attempt to change, alter or modify the engine fuel
system in any way that might affect safety or compliance with
applicable codes and standards.
WHILE OPERATING
•This engine was designed and manufactured for specific
applications. Do not attempt to modify the equipment or
use it for any application for which it was not designed.
• Engine exhaust gases contain DEADLY carbon monoxide
gas.This dangerous gas, if breathed in sufficient
concentrations, can cause unconsciousness or even death.
Operate this equipment only in the open air where adequate
ventilation is available.
• Do not insert any object through the cooling slots of the
engine.You could damage the equipment or injure yourself.
• Do not operate the engine faster than the speed necessary to
operate the equipment. Do not run the engine at high speed
when not operating the equipment.
• This engine requires an adequate flow of cooling air for its
continued proper operation. Never operate the equipment
inside any room or enclosure where the free flow of cooling air
into and out of the equipment might be obstructed. Without
sufficient cooling air flow, the engine quickly overheats,
damaging the engine or nearby property.
• Do not smoke around the engine. Wipe up any fuel or oil spills
immediately. Never leave oily or fuel soaked rags around the
engine. Keep the area around the engine clean and free of
debris.
• Keep hands, feet, clothing, etc., away from moving parts of
this engine.
• Never operate the engine (a) in the rain; (b) in any enclosed
compartment; (c) if the engine speed changes; (d) if the
engine sparks; (e) if flame or smoke is observed while the
engine is running.
• Never work on this engine or handle any electrical device
while standing in water, while barefoot, or while hands or feet
are wet. DANGEROUS ELECTRIC SHOCK will result.

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When ordering engine components, you must provide the
authorized service dealer with the engine identification number,
which is located on the engine identification decal. See the
illustration below for the location of the decal.
This engine meets the 1998 and later California emissions
regulations.To ensure that your engine continues to meet
these regulations, refer to the following information and
instructions in this owner’s manual.
SERVICE INFORMATION
Service on this engine within and after the warranty
period can be performed by any authorized service
dealer. Service technicians are factory trained and
capable of handling all service needs.
When contacting an authorized service dealer or the
factory about parts and service, always supply the
complete model number and serial number of your unit as
given on its data plate decal.
The warranty and replacement parts for this engine are
included in the owner’s manual.
TABLE OF CONTENTS
RULES FOR SAFE OPERATION..........................................2-3
GENERAL INFORMATION....................................................4-5
Service Information ..................................................................4
Engine Identification Decal Location ........................................4
Oil and Fuel Information............................................................5
OPERATION ..........................................................................6-7
Before Starting the Engine........................................................6
Starting the Engine ................................................................6-7
Stopping the Engine..................................................................7
Low Pressure Shutdown System ..............................................7
MAINTENANCE ..................................................................8-13
General Maintenance Recommendations ................................8
Service and Adjustments ....................................................8-10
Carburetor Adjustments ..........................................................11
Checking/Adjusting Valve to Rocker Arm Clearance ..............11
Retorquing Head Bolts ......................................................11-12
Maintenance Schedule............................................................12
Storage Instructions ................................................................13
Specifications ..........................................................................13
PARTS LISTS & EXPLODED VIEWS ..............................14-21
WARRANTIES ..................................................................22-24
California Emission Control Warranty Statement....................22
Emission Control System Warranty ........................................23
Generac Engine Warranty ........................................Back Cover
Generac Corporation
Eng. Identif. No. XXXXXX
Displacement XXXXXX
Decal

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OIL AND FUEL INFORMATION
NOTE: BE SURE TO READ THESE INSTRUCTIONS
CAREFULLY BEFORE ATTEMPTING TO START OR
OPERATE THIS EQUIPMENT. Using old or improper oil or
fuel can cause engine damage.
CAUTION: Any attempt to crank or start the engine
before it has been properly serviced with the
recommended oil may result in engine damage.
RECOMMENDED OIL TYPE
Using the proper type and weight of oil in the crankcase is
extremely important. Check the oil before each use and change
the oil regularly. Failure to use the correct oil, or using dirty oil,
can cause premature engine wear and failure.
The recommended oils include the following:
• During summer months: SAE 10W-30,
• During winter months: SAE 5W-20 or 5W-30. DO NOT USE
SAE 10W-40.
The crankcase oil capacity is about 1500 ml (51 oz.) with the oil
filter. Without the filter, the oil capacity is 1350ml (46 oz.). Use no
special additives.
RECOMMENDED FUEL TYPE
Use clean, fresh, regular UNLEADED gasoline with this engine.
CAUTION: Do not overfill the fuel tank. Always allow
room for fuel expansion.
WARNING: NEVER FILL THE FUEL TANK INDOORS. OR
WHEN THE ENGINE IS RUNNING OR HOT. DO NOT
LIGHT A CIGARETTE OR SMOKE WHEN FILLING THE
FUEL TANK.

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OPERATION AND MAINTENANCE
It is the owner’s/operator's responsibility to perform all safety
checks; to make sure that all maintenance for safe operation is
performed promptly; and to have the engine checked by an
authorized dealer periodically. Normal maintenance service and
replacement of parts are the responsibility of the owner/operator
and, as such, are not considered defects in materials or
workmanship within the terms of the warranty. Individual
operating habits and usage contribute to the need for
maintenance service.
Proper maintenance and care of your engine assures a minimum
number of problems and keeps your operating expenses at a
minimum. See your authorized dealer/distributor for service aids
and accessories.
BEFORE STARTING THE ENGINE
Perform the following tasks before trying to start the engine:
ADDING ENGINE OIL
1. Remove the yellow oil fill cap from the crankcase (Figure 1).
2. Add engine oil until the oil level is to the point of overflowing.
Figure 1 — Oil Fill Cap
CHECKING ENGINE OIL
1. Check the engine oil level before starting the engine each
time after the initial start. If the oil level is below the point of
overflowing, fill to the proper level.
ADDING FUEL
1. Fill the fuel tank using clean, fresh UNLEADED gasoline.
STARTING THE ENGINE
1. Open the fuel shut-off valve, if so equipped.
2. If your unit is equipped with the IDLE/CONTROL feature,
locate the IDLE/CONTROL ON/OFF SWITCH on the control
panel, and set it to the OFF (O) position.
3. Locate the RUN/STOP SWITCH (Figure 2) next to the
engine cylinder head and push it to RUN.
Figure 2 — RUN/STOP SWITCH
If your engine is equipped with a choke, use the
following instructions:
1. Place the choke lever in the FULL CHOKE POSITION
(Figure 3) by sliding it to the left (towards the valve cover),
in the direction indicated by the arrow.
Figure 3 — Choke Position
2. Grasp the recoil handle (Figure 4) and pull it slowly until you
feel slight resistance, then PULL QUICKLY.
LOWOIL
CHOKE
OHVI
LOWOIL
CHOKE
OHVI
Oil Fill
Cap
RUN / STOP SWITCH
LOW OIL LIGHT
CHOKE LEVER

A If the engine FAILS TO START, go to Step 3.
B. If the engine STARTS, go to Step 4.
Figure 4 — Recoil Handle
3. Move the choke lever to the HALF CHOKE POSITION,
and pull the recoil handle (Figure 4) two (2) times.
• If the engine STILL FAILS TO START, repeat
Steps 1-3.
4. Move the choke lever to the RUN POSITION by sliding it
to the right (away from the valve cover and under the
arrow).
5. Allow the engine to warm up for two (2) minutes before
using the equipment.
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STOPPING THE ENGINE
1. Remove the load on the engine, and let it run for 30
seconds.
2. Turn off the engine by moving the RUN/STOP SWITCH to
the STOP position.
3. Close the fuel shut-off valve, if so equipped.
LOW PRESSURE SHUTDOWN SYSTEM
The engine is equipped with a low oil pressure sensor that shuts
down the engine automatically when the oil pressure drops below 8
psi ). If the engine shuts down by itself and the fuel tank has
enough gasoline, check the engine oil level.
INITIAL STARTUP
A delay built in the shutdown system allows oil pressure to build
during starting. The delay allows the engine to run for about 10
seconds before sensing oil pressure.
SENSING LOW PRESSURE
If the system senses low oil pressure during operation, the
engine shuts down. As the system shuts down, the low oil light
comes ON (see Figure 2, page 6). However, once the engine
stops rotating, this light will go OFF.
RESTARTING THE ENGINE
If you try to restart the engine within (five) 5 seconds after it
shuts down, the engine may NOT start.The system needs 5 to
10 seconds to reset.
NOTE: If you do restart engine after a shutdown and have not
corrected the low oil pressure, the engine will run for
about 10 seconds as described above, and then it will stop.
Recoil Handle

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GENERAL MAINTENANCE
RECOMMENDATIONS
The owner/operator is responsible for making sure that all periodic
maintenance tasks are completed on a timely basis; that all
discrepancies are corrected; and that the equipment is kept clean
and properly stored. Never operate a damaged or defective
engine.
CAUTION: Disconnect the spark plug wire from the spark
plug, and place the wire where it cannot come in contact
with the spark plug before working on this engine.
CHECKING THE OIL LEVEL
See the BEFORE STARTING THE ENGINE section on page 6 for
information on checking the oil level.The oil level should be
checked before each use, or at least every eight (8) hours of
operation. Keep the oil level maintained.
CHANGING THE OIL AND OIL FILTER
Your engine may be equipped with an oil filter. Change the oil and
filter after the first eight (8) hours of operation. Change the oil
and oil filter (if so equipped) every 50 hours thereafter. If you are
using this engine under dirty or dusty conditions, or in extremely
hot weather, change the oil more often.
Use the following instructions to change the oil while the engine is
still warm:
1. Clean the area around the oil drain plug, remove the plug and
drain the oil completely into a suitable container (Figure 5).
Figure 5 — Oil Filter and Drain Plug
2. When the oil is drained, install and tighten the oil drain
plug.
3. If your engine is equipped with an oil filter, use the
following instructions:
A. Place a suitable container beneath the oil filter and
turn the filter counterclockwise to remove the filter.
B. Coat the gasket of a new filter with engine oil.Turn
the new filter clockwise until the gasket contacts the
filter adapter, then tighten an additional 3/4 turn.
4. Remove the oil fill plug and insert a clean funnel into the
plug opening. Fill the crankcase with the recommended
oil until the oil level is at point of overflowing. Approxi-
mately 1350ml (46 oz.) are required without an oil filter;
1500ml (51 oz.) with an oil filter. POUR SLOWLY.
5. When the crankcase is filled to the proper level, install
and tighten the oil fill plug.
SERVICING THE AIR CLEANER .
Your equipment’s air cleaner is one of the most important
areas to maintain.This engine will not run properly and may
get damaged if it is run with a dirty air cleaner system.
Clean or replace the paper air filter (Figure 6) every 50
hours of operation or once a year, whichever comes first.
Clean or replace the filter more often if the engine is operated
under dusty or dirty conditions. Clean the foam pre-filter
every 25 hours of operation, or sooner under dusty or dirty
conditions.
Oil Filter
Drain Plug

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CAUTION: Never run this equipment without the complete
air cleaner system installed on the engine.This could result
in premature wear to the engine.
Use the following instructions to clean or replace the
air cleaner components.
1. Loosen the two screws on the air cleaner cover. Remove the
air cleaner cover (Figure 6).
Figure 6 — Removing the Air Cleaner Cover
2. Remove the paper air filter and the foam pre-filter from the
air cleaner cover (Figure 7).
Figure 7 — Air Cleaner Components
CHOKE
CHOKE
3. To clean or replace the foam pre-filter:
A. Wash the pre-filter in soapy water.
B. Squeeze the pre-filter dry with a clean cloth. DO
NOT TWIST.
NOTE: If the pre-filter is still dirty after washing and drying it,
replace it with a new one.
C. Apply enough clean engine oil to saturate the pre-
filter.
D. Wrap the pre-filter in a clean dry cloth and squeeze
out the excess oil. DO NOT TWIST. Set the pre-filter
aside.
4. To clean or replace the paper air filter:
A. Clean the air filter by tapping it gently on a solid
surface.
NOTE: If the filter is too dirty, replace it with a new one.
Dispose of the old filter properly.
5. Clean the air cleaner cover.
6. Insert the pre-filter into the cover, then the paper air
filter (see Figure 7).
7. Reinstall the air cleaner cover and tighten the two (2)
screws (see Figure 6).
REPLACING THE SPARK PLUG
Use a Champion RC12YC spark plug or equivalent.The
correct air gap is 0.76mm (0.030 in.). Remove the plug every
100 hours of operation or once each year, whichever comes
first.This will help your engine to start easier and run better.
1. Stop the engine and pull the spark plug wire off of the
spark plug.
2. Clean around the spark plug and remove it from the
cylinder head.
Foam
Pre-Filter may
stick to cover
Paper
Filter
Foam
Pre-Filter

Generac GN-320/360/410 Engine
— 10 —
Figure 9 — Removing Heat Shield
SERVICE AND ADJUSTMENTS
ENGINE SPEED
CAUTION: The engine speed was properly adjusted at the
factory and should require no additional adjustment. Do
not attempt to change engine speed. If you believe the
engine is running too fast or too slow, take your engine to
an authorized service center for repair and adjustment.
CHANGING THE ENGINE GOVERNED SPEED WILL
VOID THE ENGINE WARRANTY.
Your engine runs at a constant speed. This constant operating
speed is maintained by a mechanical, flyweight type, fixed
speed governor. DO NOT try to adjust the governed speed
setting for the following reasons:
• Operating the engine at high engine speeds is dangerous and
increases the risk of personal injury or damage to the
equipment.
• Operating the engine at low engine speeds with heavy loads may
shorten the engine’s life.
3. Set the spark plug gap (Figure 8) to 0.76mm (0.030 in.).
Install a correctly gapped spark plug into the cylinder head.
Figure 8 — Setting Spark Plug Gap
CLEANING THE SPARK ARRESTOR
SCREEN
The engine exhaust muffler has a spark arrestor screen. Inspect
and clean the screen every 100 hours of operation or once
each year, whichever comes first.
NOTE: If you use your engine on any forest-covered, brush-
covered or grass-covered unimproved land, it must
have a spark arrestor.The spark arrestor must be
maintained in good condition by the owner/operator.
Clean and inspect the spark arrestor screen as follows:
Inspect the screen and replace if it is torn, perforated or otherwise
damaged (see Steps 1-4 below).DO NOT USE a defective screen. If
the screen is not damaged, clean it with a commercial solvent.
If the spark arrestor is found to be damaged or defective, replace it
as follows:
1. Remove the four (4) screws that connect the heat shield to
the muffler (Figure 9).
2. Remove the four (4) screws that attach the spark arrestor
screen (Figure 9).
3. Replace damaged screen with new screen (Part No. 83083).
4. Reattach the screen and the heat shield with the four (4)
screws. Resintall the heat shield to the muffler with the four
(4) screws.
Spark
Arrestor
Screen
83083
Heat Shield
SET PLUG GAP AT 0.76 mm
(0.030 inch)

3. Loosen the rocker arm jam nut. Using an allen wrench to turn
the pivot ball stud, check the clearance between the rocker
arm and the valve stem with a flat feeler gauge (Figure 11).
Figure 11 — Adjusting Valve to Rocker Arm Clearance
4. When the valve clearance is correct, hold the pivot ball stud
with the allen wrench and tighten the rocker arm jam nut.
Torque the jam nut to 7.15-9.35 N-m (65-85 in-lb). After
tightening the jam nut, recheck the valve clearance to make
sure it did not change (see Figure 11).
5. Reinstall the rocker cover gasket, rocker cover and
the four (4) screws (see Figure 10).
Tighten Jam Nut to
65-85 inch-pounds
Allen Wrench
Feeler Gauge
Loosen Jam Nut,
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CARBURETOR ADJUSTMENTS
The carburetor of your engine is pre-set at the factory. The
carburetor should not be tampered with because this will VOID
THE EMISSION CONTROL SYSTEM WARRANTY. If you
experience problems and your engine is used at an altitude in
excess of 5000 feet, contact the nearest authorized dealer
regarding high altitude setting changes.
CHECKING/ADJUSTING VALVE TO
ROCKER ARM CLEARANCE
Every 50 hours of operation, remove the rocker cover and
check the valve to rocker arm clearance.
When adjusting the clearance, the engine should be at room
temperature, and the piston should be at Top Dead Center
(TDC) of its compression stroke (both valves are closed). The
correct clearance is 0.05-0.1mm (0.002-0.004 in.). Check and
adjust the valve to rocker arm clearance as follows:
1. Remove the four (4) screws from the rocker cover
(Figure 10).
2. Remove the rocker cover and rocker cover gasket.
Figure 10 —Removing the Valve Cover
OHVI LOW
OI

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RETORQUING THE HEAD BOLTS
After the first 50 hours of operation, retorque the head bolts.
NOTE: Only perform this adjustment after the first 50 hours of
operation.The head bolts will need no further adjustment.
1. Remove the four (4) screws from the rocker cover
(see Figure 10).
2. Remove the rocker cover and rocker cover gasket.
3. Torque the bolts to 6.9 kg-m. (44 ft-lb).
4. Torque the bolts in the following sequence: A, B, C, D, (star
pattern). See Figure 12.
Figure 12 — Tightening Sequence
C
B
D
A
MAINTENANCE SCHEDULE
Every 8 Hours or 25 Hours or Every 50 Hours or Every 100 Hours or Every
MAINTENANCE OPERATION or Daily Season Season Season
Check Oil Level X
Change Oil See Note 1
Change Oil Filter (if so equipped) See Note 1
Service Air Filter Foam Pre-Filter Paper Filter (Note 2)
Replace or Clean Spark Plug X
Clean Spark Arrestor Screen X
Adjust Valve Clearance X
Retorque Head Bolts See Note 3
NOTE 1: Change oil and filter after first 8 hours of operation and then every 50 hours thereafter. Change sooner when operating under heavy load or
in dusty or dirty environment or in high ambient temperature.
NOTE 2: Clean more often when operating under dirty or dusty conditions.
NOTE 3: Perform this task ONLY after first 50 hours of operation. Head bolts will NOT need further retorquing.

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STORAGE INSTRUCTIONS
This engine should be started at least once a week and run for at
least 30 minutes. If this cannot be done and the equipment must
be stored for more than 30 days, use the following guidelines to
prepare it for storage.
WARNING: Never store the engine with the fuel in the tank
indoors or in an enclosed, poorly ventilated areas, where
fumes can reach an open flame spark or pilot light as on a
furnace, water heater, or clothes dryer.
1. Run the engine for about five (5) minutes to warm it.
NOTE: Alcohol-blended fuel, or “gasohol”, attracts moisture which
can lead to the separation and formation of acids during
storage.This acidic gas can damage internal engine parts.
Methanol, ethanol and grain alcohol all are forms of
gasohol. If you did use “gasohol,” drain the fuel tank, then
run the engine until it stops from lack of fuel.
WARNING: Drain the fuel into approved container outdoors,
away from open flame. Be sure the engine is cool.
NOTE: Using a fuel additive such as STA-BIL® fuel stabilizer, or an
equivalent, will prevent gum deposits from forming in the
engine’s fuel system.
2. While the engine is still warm, drain the oil from the
crankcase. Refill with it with fresh oil. See BEFORE
STARTING ENGINE on Page 6 for oil recommendations.
3. Remove spark plug and pour about 1/2 ounce (15ml) of
engine oil into the cylinder. Crank slowly to distribute oil.
CAUTION: Avoid spray from the spark plug hole when
cranking the engine slowly.
4. Install the spark plug. Do not connect the spark plug wire.
5. Clean the dirt, oil and grease from the cylinder, cylinder head,
fins, blower housing, rotating screen and muffler area.
6. Close the fuel shut-off valve.
OTHER STORAGE TIPS
1. Do not store gasoline from one season to another.
2. Replace the gasoline can if it starts to rust. Rust and/or dirt
in a gasoline can cause problems when you use that fuel
with this equipment.
3. Store the equipment in a clean and dry area.
SPECIFICATIONS
Model GN-320 GN-360 GN-410
Bore 80mm 85mm 90mm
Stroke 64mm 64mm 64mm
Valve Clearance 0.05–0.10mm 0.05–0.10mm 0.05–0.10mm
Displacement 321cc 363cc 407cc
Maximum Tilt Angle
While Operating 15° 15° 15°
Oil Capacity with Oil 1500ml 1500ml 1500ml
Filter (51 oz.) (51 oz.) (51 oz.)
Oil Capacity without Oil 1350 ml 1350 ml 1350 ml
Filter (46 oz.) (46 oz.) (46 oz.)

— 14 —
Generac GN-320/360/410 Engine EEXXPPLLOODDEEDDVVIIEEWW——LLOONNGGBBLLOOCCKK((GGNN--332200//336600//441100))
10C
21A
21B
3C
4C

— 15 —
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RREEPPAAIIRRPPAARRTTSSLLIISSTT——LLOONNGGBBLLOOCCKK((GGNN--332200//336600//441100))
ITEM PART NO. QTY. DESCRIPTION
1 71978 1 Connecting Rod With Cap
and Bolt
2 71980 1 Piston Pin
3A 89291 1 Piston Ring Set 80 MM (320)
3B 71977 1 Piston Ring Set 85 MM (360)
3C 21533 1 Piston Ring Set 90 MM (410)
4A 89217 1 Piston 80 MM (320)
4B 76339 1 Piston (360)
4C 96699 1 Piston (410)
5 71983 2 Piston Pin Retainer
6A 78666A 1 Crankshaft Assembly With
Gears (Small Taper)
6B 76378A 1 Crankshaft Assembly With
Gears (Straight Shaft)
7 A7628 1 Governor Arm
8 78658 1 Governor Arm “R” Pin
9 78659 2 Governor Arm Washer
10A 88261D 1 Crankcase H.S. W/Taper Plugs
(320)
10B 88261C 1 Crankcase H.S. W/Taper Plugs
(360)
10C 88261E 1 Crankcase H.S. W/Taper Plugs
(410)
12 72655 2 Crankshaft Seal
13 A8930 1 Gov. Gear Assembly
14 78645 1 Governor Retainer
(“C” Ring)
15 A7811 1 Governor Spool
19 A7081 1 Camshaft Assembly
20 76701 1 Crankcase Gasket
21A 21713A 1 Cylinder Head Gasket
(320-360)
21B 21713B 1 Cylinder Head Gasket (410)
22 78691 1 Oil Pressure Reliefcover
23 A5771 1 Pressure Relief Spring
24 A5776 1 Pressure Relief Ball
25 76361 1 Thrust Washer
26 A8898B 1 Gear Cover
27 86514 2 Valve Spring Retainer
28 91308 2 Valve Spring
ITEM PART NO. QTY. DESCRIPTION
29 86025 1 Gerotor Set
30 84430 1 Balancer
31 21714 1 Cylinder Head With Valve
Seats & Guides
32 86516 1 Exhaust Valve
33 86517 1 Intake Valve
34 88396B 2 Push Rod
35 83897 2 Tappet
36 77158 1 Oil Pick-Up Assembly
37 71987 1 Rocker Cover Gasket
38 72694 2 Pivot Ball Stud
39 83907 2 Rocker Arm
40 72696 2 Jam Nut (Rocker Arm)
41 78694 1 Push Rod Guide Plate
42 21742 4 M10-1.5 x 105 Head Bolt
43 83938 1 Rocker Cover Breather
Assembly
44 76329 1 Oil Fill Plug
46 86254 1 O-Ring 17.8 I.D. x 2.4 THK.
47 26925 2 3/8" NPT Pipe Plug
48 74908 1 M5-0.8 x 8MM Screw
(Thread Forming)
50 86515 4 Valve Spring Keeper
51 78606 4 M6-1 x 12MM Pan Head
Screw & Lockwasher
52 A1442 8 Hex Head Flange Bolt
M8-1.25 x 42MM
53 78672 1 Valve Stem Seal
54 89673 2 Valve Spring Washer
N/A 21947C 1 Long Block Assm. (320cc
w/item 6A
N/A 21948C 1 Long Block Assm. (360cc
w/item 6A
N/A 21949C 1 Long Block Assm. (360cc
w/item 6B
N/A A1044A 1 Long Block Assm. (410cc
w/item 6A
N/A A6497A 1 Long Block Assm. (410cc
w/item 6B

— 16 —
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43A
43B
43C

— 17 —
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ITEM DESCRIPTION PART NO. QTY. ITEM DESCRIPTION PART NO. QTY.
31 Breather Hose 72745 1
32 Manifold Head Gasket 91039 1
33 M6 x 20 SHCS 40945 2
34 Carburetor Bolt 81647 2
35 M6 x 12 HHCS 66476 2
36 K Adapter 91028 1
37 M6 Lock Washer 22097 3
38 M6 Hex Nut 49813 2
39 Carburetor/Air Box 90970 1
Gasket
40 M6 Ribbed Lock- 93873 2
washer
41 Spitback Plate 91204 1
42 Carburetor/Manifold 89228 1
Gasket
43A 320 Nikki Carburetor 93302A 1
43B 360 Nikki Carburetor 91187A 1
43C 410 Nikki Carburetor A4600 1
44 Air Cleaner Base 73108A 1
45 M6 Flatwasher 49811 4
46 #8 x 3/8" Plastite 59635 1
Screw
47 Air Filter 73111 1
48 Precleaner 81646 1
49 Choke Knob 83504 1
50 M6 x 16 HHCS 47411 2
51 Bracket Air Box 90827 1
60 1/4” ID Hose 30340 12”
61 Hose Clamp 48031C 1

— 18 —
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ITEM PART # QTY. DESCRIPTION
22 40976 2 SHCS M8-1.25 X 20
26 22129 2 Lock Washer M8
94 B2348 1 Tank Cradle
95 52858 2 M8 Lock Nut
96 59012 2 M8 X 20 FLHCS
97 96083 1 Front Tank Bracket
98 96084 1 Rear Tank Bracket
99 89263 1 Dipstick ASM
100 A6558 1 Oil Fill/Check Tube

— 19 —
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EEXXPPLLOODDEEDDVVIIEEWW——OOIILLFFIILLTTEERRAANNDDOOPPTTIIOONNAALLOOIILLFFIILLLLTTUUBBEE
ITEM PART # QTY. DESCRIPTION
2 86999 1 Oil Filter Gasket
3A 72709 1 Oil Blockoff
3B 94683 1 Oil Filter Adapter
4 49821 2 M8 X 30 SHCS
5 99236 1 Oil Press Switch
6 70185 1 Oil Filter

— 20 —
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EEXXPPLLOODDEEDDVVIIEEWW——LLOOWWOOIILLSSHHUUTTDDOOWWNNAANNDDGGOOVVEERRNNOORR
ITEM PART # QTY. DESCRIPTION
7 78653 1 Run/Stop Switch
8 85272 1 LED Assembly
9 93104 1 L.O.S. Decal
10 93611 1 Black Sleeving
12 84329 1 3 Pin Male HSG
13 92981 1 Wire Assembly
14 22097 2 M6 Lockwasher
15 92079 2 M6 X 30 Taptite
16 84542 1 Ignition Coil
18 87221B 1 L.O.S. Module
20 72347 1 Sparkplug
ITEM PART # QTY. DESCRIPTION
21 72734 1 Governor Lever
23 83502 1 Adjust Screw
24 83512 2 M8 X 15 Taptite
25 73100 1 60Hz Gov. Spring
27 83503 1 M5 Lock Nut
28 73101 1 Governor Brkt.
29 72735 1 Governor Rod
30 72789 1 Anti-Lash Spring
101 83782 1 Idle Coil ASM
102 66311 1 M8 — 1.25 Jam Nut