Home›Engines›Generac GN-480

Generac GN-480 Engine

Name: Generac GN-480 Engine
Brand: Generac

The Generac GN-480 is a 0.48 L 2-cylinder natural engine rated at 3600 rpm, producing up to 11.9 kW. It powers generator sets from Generac, including the NP-66G, NP-66LPG, PP50G and PP70G. It holds 1.7 L (0.4 gal) of oil.

Also known as: Generac GN-480

Part of the Generac GN-480 engine family — 4 variants share parts & fitment.

0.48 L

Displacement

Cylinders

3600 rpm

Rated speed

11 kW

Gross power

On this pageSpecs Generator sets Maintenance FAQ Service intervals Torque & specs Fluids Procedures Wiring

Engine specifications

Oil capacity	1.7 L
Displacement	0.48 L
Cylinders	2
Aspiration	natural
Rated speed	3600 rpm
Gross power	11 kW

Generator sets powered by this engine

Generac NP-66G Generac NP-66LPG Generac PP50G Generac PP70GGenerac PRIMEPACT 55GGenerac PRIMEPACT 55LP Generac PRIMEPACT 66G Generac PRIMEPACT 66LP Generac PRIMEPACT 70 Generac Q-55G Generac Q-55LP Generac Q-70G

How to read your Generac engine serial & model number →

Common problems

Engine won't crank.
Cause: 1. 15 amp fuse blown. 2. Loose, or corroded or defective battery cable(s). 3. Battery is discharged or defective. 4. Defective starter contactor. 5. Defective starter motor. 6. Defective Start/Stop switch.
Fix: 1. Replace blown fuse. 2. Tighten, clean or replace, as necessary. 3. Recharge or replace battery. 4. Replace starter contactor. 5. Replace starter motor. 6. Replace switch.
Engine starts hard, runs rough.
Cause: 1. Dirty engine air cleaner. 2. Automatic choke is sticking. 3. Defective spark plugs. 4. Defective ignition magneto.
Fix: 1. Clean or replace as needed. 2. Free choke linkage as needed. 3. Clean, regap or replace. 4. Replace it if defective.
No AC output voltage.
Cause: 1. Main breaker(s) open. 2. Transfer switch (if so equipped) is set to wrong position. 3. Failure in vehicle electrical system. 4. Generator component failure.
Fix: 1. Close main breaker(s). 2. Reset transfer switch. 3. See vehicle manual. 4. Contact an authorized service facility.
Engine starts, then shuts down.
Cause: 1. Engine oil level is low. 2. Bad low air pressure switch. 3. Defective high temp switch. 4. Water in fuel.
Fix: 1. Add oil as needed. 2. Replace, if bad. 3. Replace, if bad. 4. Drain fuel tank and refill.
Engine cranks, won't start.
Cause: 1. Out of fuel. 2. Fuel shutoff valve is closed. 3. Fuel pump not operating. 4. Automatic choke not operating properly. 5. Engine is flooded. 6. Fuel filter is clogged. 7. Engine spark plugs defective. 8. Bad ignition magneto on engine. 9. Bad carburetor. 10. Dirty air cleaner.
Fix: 1. Refill fuel tank. 2. Open fuel shutoff valve(s). 3. Repair or replace pump. 4. Repair, replace or adjust. 5. Wait 5-10 minutes: try again. 6. Replace filter if clogged. 7. Clean, regap or replace as needed. 8. Replace if defective. 9. Adjust, repair or replace. 10. Clean or replace as needed.
Engine won't crank
Cause: 15 amp fuse blown. Loose, corroded or defective battery cable(s). Battery is discharged or defective. Defective starter contactor. Defective starter motor. Defective control relay (CR1).
Fix: 1. Replace blown fuse. 2. Tighten, clean or replace, as necessary. 3. Recharge or replace battery. 4. Replace starter contactor. 5. Replace starter motor. 6. Replace control relay.
Engine cranks, won't start
Cause: Out of fuel. Fuel shutoff valve is closed. Fuel pump not operating. Automatic choke not operating properly. Engine is flooded. Fuel filter is clogged. Defective Controller Circuit Board. Engine spark plugs defective. Bad ignition magneto on engine. Bad carburetor. Dirty air cleaner.
Fix: 1. Refill fuel tank. 2. Open fuel shutoff valve(s). 3. Repair or replace pump. 4. Repair, replace or adjust properly. 5. Wait 5-10 minutes; try again. 6. Replace filter if clogged. 7. Replace bad circuit board. 8. Clean, regap or replace as needed. 9. Replace if defective, 10. Adjust, repair or replace. 11. Clean or replace as needed.
No AC output voltage
Cause: 1. Main breaker(s) open. 2. Transfer switch (if so equipped) is set to wrong position. 3. Failure in vehicle electrical system. 4. Generator component failure.
Fix: 1. Close main breaker(s). 2. Reset transfer switch. 3. See vehicle manual. 4. Contact authorized service facility.
Generator overheating and shutdown
Cause: Insufficient cooling and ventilating air flow
Fix: Ensure air inlet and outlet openings in generator compartment are open and unobstructed
Exhaust gases entering vehicle interior
Cause: Openings in the vehicle that might permit exhaust gases to enter
Fix: Close windows, doors, and other openings in the vehicle
Engine won’t crank
Cause: 1. 15 amp fuse blown. 2. Loose, corroded or defective battery cable(s). 3. Battery is discharged or defective. 4. Defective starter contactor. 5. Defective starter motor. 6. Defective control relay (CR1).
Fix: 1. Replace blown fuse. 2. Tighten, clean or replace, as necessary. 3. Recharge or replace battery. 4. Replace starter contactor. 5. - Replace starter motor. 6. Replace control relay.
Engine starts, then shuts down
Cause: 1. Engine oil level is low 2. Bad control relay (CR1). 3. Bad low oil pressure switch. 4. Bad control relay (CR2). 5. Water in fuel.
Fix: 1. Add oil as needed. 2. Replace if bad (CR1). 3. Replace, if bad. 4. Replace bad relay (CR2). 5. Drain fuel tank and refill.
Engine starts hard, runs rough
Cause: 1. Dirty engine air cleaner.
Fix: 1. Clean or replace as needed.
Engine failure
Cause: Attempted cranking or starting engine before proper oil servicing
Fix: Properly service engine crankcase with recommended oil
Engine does not start after cranking for 15 seconds
Fix: Release the start/stop switch and try again

Compiled from service & troubleshooting documentation across every generator set that uses the Generac GN-480.

Maintenance schedule

Item	Spec	Capacity	Part #	Interval
Air filter	Foam precleaner, wash in liquid detergent and water, re-oil with clean engine oil		069341	25 hr	Amazon eBay
Fuel filter			072375	100 hr	eBay
Oil filter	FRAM #PH3614		070185	100 hr	Amazon $28.95 eBay $30.00 FridayParts $45.99
Battery	Fill unsealed batteries with Distilled Water only; check state of charge with automotive-type hydrometer every six months		—	12 hr
Belt	40 in.		075216		Amazon eBay
Oil	SAE 10W-30, API classification "For Service SF"	1.7 liters	—	100 hr
Spark plug	Champion RC12YC; alternate Fram Autolite 65; gap 0.030 inch (0.76 mm)		072347	100 hr	Amazon $34.90 eBay $1.99

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Service intervals

Item	Action	Hours	Months	Notes
Engine crankcase oil	Check	8 hr		check at least every 8 hours of operation or before use
Engine crankcase oil level	Check	8 hr		or before each use
Engine oil level	Check	8 hr		at least every eight hours of operation, or before use
25-hour break-in check-up	Inspect	25 hr		First service — Change crankcase oil and oil filter; inspect cooling/ventilation openings, ignition, electrical and exhaust systems
Air cleaner foam pre-cleaner	Clean	25 hr	3 mo	whichever occurs first; clean and re-oil
All fluid levels	Check	25 hr		First service — 25-Hour Check Up
Cooling and ventilation openings	Inspect	25 hr		First service — part of 25-hour check up
Cooling and ventilation openings (25-hour checkup)	Inspect	25 hr		First service
Cooling and ventilation openings on the vehicle	Inspect	25 hr		First service — 25-Hour Check Up
Electrical system	Inspect	25 hr		First service — part of 25-hour check up
Electrical system (25-hour checkup)	Inspect	25 hr		First service
Engine carburetor adjustments	Check	25 hr		First service — part of 25-hour check up
Engine crankcase oil and oil filter	Change	25 hr		First service — First change after the 25-hour break-in period
Engine crankcase oil and oil filter (25-hour checkup)	Change	25 hr		First service — performed by Generac Authorized Service Dealer after break-in
Engine exhaust system	Inspect	25 hr		First service — part of 25-hour check up
Engine ignition system	Check	25 hr		First service — part of 25-hour check up
Engine oil and oil filter	Change	25 hr		First service — 25-hour check up.
Entire electrical system	Inspect	25 hr		First service — Part of 25-Hour Check Up
Exhaust system (25-hour checkup)	Inspect	25 hr		First service
Fluid levels	Check	25 hr		First service — part of 25-hour check up
Fluid levels (25-hour checkup)	Check	25 hr		First service
Foam pre-cleaner	Clean	25 hr	3 mo	whichever occurs first
Foam precleaner	Clean	25 hr	3 mo	Whichever occurs first; more often in dusty conditions
Foam precleaner (air cleaner)	Clean	25 hr	3 mo	clean and re-oil every three months or every 25 hours, whichever occurs first
Ignition system (25-hour checkup)	Check	25 hr		First service
Engine crankcase oil	Change	100 hr		First service — change more frequently under heavy load or high ambient temperature
Engine oil	Change	100 hr		First service — thereafter; more often under heavy load/high ambient
Air cleaner paper filter	Replace	100 hr	12 mo	whichever comes first; must be flame retardent type
Air intake screen	Clean	100 hr		at least every 100 hours; clean more often if necessary
Engine oil filter	Change	100 hr		First service — thereafter
Engine oil filter	Replace	100 hr		First service
Engine spark plugs	Clean	100 hr		reset gap to 0.030 inch (0.8 mm)
Fuel filter	Replace	100 hr	12 mo	whichever comes first
Fuel filter (gasoline only)	Replace	100 hr	12 mo	once each year or every 100 hours, whichever comes first
Oil filter	Change	100 hr		First service — Change after first 25 hours, then every 100 operating hours
Oil filter	Replace	100 hr		First service — every 100 operating hours thereafter
Paper air filter	Replace	100 hr	12 mo	whichever comes first
Spark plug	Clean	100 hr		clean and reset gap to 0.030 in (0.76 mm) every 100 hours
Spark plug gap	Adjust	100 hr		Adjust gap to 0.030 inch (0.76 mm)
Spark plugs	Clean	100 hr		reset gap to 0.030 inch (0.8mm); do not blast clean

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Service specifications

Type	Item	Value	Unit	Condition
Clearance	Clearance between exhaust system parts and combustible material	3	inches (76 mm)	minimum
Clearance	Clearance between fuel line and exhaust system parts	2	inches (51 mm)	minimum
Clearance	Compartment clearance - back	1/2	inch (13 mm)	minimum; suspended mount recommends at least 1/2 inch
Clearance	Compartment clearance - front and top	1/2	inch (13 mm)	after compartment lined with metal and sound insulation
Clearance	Compartment clearance - sides	1	inch (25 mm)	minimum
Gap	Spark plug gap	0.030	inch (0.76 mm)
Gap	Spark plug gap	0.030 inch (0.76 mm)	inch (mm)
Gap	Spark plug gap	0.030 inch (0.8 mm)	inch (0.8 mm)
Gap	Spark plug gap	0.030 inch (0.8mm)	inch
Gap	Spark plug gap	0.8	mm
Gap	Spark plug gap (Section 3.5)	0.030 inch (0.76 mm)	inch (0.76 mm)
Other	Battery cable size by length	0 to 10 ft (0 to 3 m) = 2; 11 to 15 ft (3.4 to 4.5 m) = 0; 16 to 20 ft (4.5 to 6 m) = 000		for warm weather use No. 2 cable up to 20 feet
Other	Battery compartment minimum ventilation opening	2	square inches	at the top of the compartment
Other	Bonding conductor	No. 8 AWG copper wire minimum		flexible conductor if replaced
Other	Circuit breakers	20 and 30	amps
Other	Compression ratio	8.6 to 1
Other	Engine crankcase capacity	1.5	U.S. quarts
Other	Engine displacement	480	cc
Other	Engine displacement	570	cc
Other	Fuel Pump Primer hold time	30	seconds	cold engine not started in more than two weeks
Other	Generator mounting bolts	3/8"-16 hardened steel bolts (Grade 5); four required		at least three threads visible past retaining lock nuts
Other	Governor speed (engine)	2900	rpm
Other	Grounding conductor minimum	No. 8 AWG	copper wire
Other	Maximum cranking time	15	seconds
Other	Minimum cooling air inlet opening	100	square inches	unrestricted; divide by free-air percentage to compensate for screens/louvers
Other	Oil capacity	1.7	liters
Other	Rated horsepower	19	hp at 3600 rpm
Other	Rated horsepower Q-55G	15	hp	at 3600
Other	Rated horsepower Q-70G	18	hp	at 3600 rpm
Other	Rated max. continuous AC output	5500	watts (5.5 kW)	120 V
Other	Rated max. continuous AC output	7000	watts (7.0 kW)	120 V
Other	Rated max. continuous current	22.9	AC amps	240 V
Other	Rated max. continuous current	29.1	AC amps	240 V
Other	Rated max. continuous current	45.8	AC amps	120 V
Other	Rated max. continuous current	58.3	AC amps	120 V
Other	Rotor poles	2	poles
Pressure	Fuel inlet pressure required	0.39	PSI
Pressure	Fuel inlet pressure required	11	inch WC
Pressure	High Temperature Switch trip point	284	F (140 C)
Pressure	LP gas fuel system leak test pressure	90	psi (620 kPa) minimum
Pressure	LP gas leak test pressure	90	psi (620 kPa)	not less than, with soap and water solution; no flame
Pressure	LP gas pressure at gaseous fuel solenoid/secondary regulator inlet	11	inches water column	optimum; do NOT exceed 14 inches water column
Pressure	Low oil pressure shutdown	8-10	PSI	switch contacts close below this pressure
Pressure	Low oil pressure shutdown	about 8-10	PSI	oil pressure switch closes below this
Pressure	Low oil pressure shutdown setpoint	2-6	PSI	oil pressure switch contacts close
Pressure	Low oil pressure shutdown switch	2-6	PSI	contacts close below this pressure
Pressure	Low oil pressure shutdown switch actuation	8-10	PSI	below this pressure switch contacts close and engine shuts down
Pressure	Low oil pressure switch	10 PSI	PSI
Pressure	Low oil pressure switch actuation	2-6 PSI	PSI
Pressure	Oil pressure shutdown	2-6	PSI
Pressure	Primary regulator outlet pressure to secondary regulator	11	inches water column (max 14)
Resistance	Fuse rating (engine DC control circuit)	15	amp
Resistance	Grounding conductor minimum size	No. 8 AWG copper		flexible conductor
Speed	Driven speed of rotor	3600	rpm
Speed	Engine RPM	2700	rpm
Speed	Engine governed speed	2500	rpm
Speed	Engine governed speed	2571	rpm
Speed	Engine governor speed	2700	rpm
Speed	Engine governor speed	3000	rpm
Speed	Engine governor speed / engine RPM	3000	rpm

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Recommended fluids

Fluid	Grade	Standard	Ambient	Capacity	Notes
Engine oil	SAE 10W-30	For Service SF		1.4 liters	Do not add any additives to the recommended oil; storage refill uses API classification For Service SE
Fuel	High quality UNLEADED gasoline (leaded REGULAR grade acceptable substitute)				Do not use gasoline containing methanol; alcohol content must not exceed 10 percent ethanol and must be removed during storage
Fuel	High quality UNLEADED gasoline (leaded regular acceptable substitute)				Gasohol not recommended; if using gasoline with alcohol, max 10% ethanol, no methanol
Fuel	High quality UNLEADED gasoline; leaded REGULAR grade gasoline is an acceptable substitute				Do not use gasoline containing alcohol (such as gasohol); if used, must not contain more than 10 percent ethanol and must be removed during storage. Do NOT use gasoline containing methanol
Fuel	High quality unleaded gasoline (leaded regular acceptable substitute)				Generac does not recommend gasoline containing alcohol; if used, not more than 10 percent ethanol and must be removed from tank during storage; do NOT use methanol
Fuel	High quality unleaded gasoline, regular grade acceptable				Gasoline containing alcohol must not contain more than 10 percent ethanol and must be removed during storage; do NOT use methanol
Fuel	LP gas (liquid propane), vapor withdrawal only	NFPA 501C			Gaseous fuel system; factory set, nonadjustable, tamper-proof to meet 1997 California Air Resources Board requirements
Fuel	LP gas (propane)				LP-vapour withdrawal fuel system as standard; requires inlet pressure of 11" WC (0.39 PSI)
Fuel	Unleaded gasoline				Leaded regular acceptable substitute. Do not use gasoline containing methanol. If alcohol, max 10% ethanol and remove during storage.
Fuel	Unleaded gasoline (leaded REGULAR acceptable substitute)				Do not use gasoline containing alcohol; if used, max 10 percent ethanol and must be removed from tank during storage. Do not use methanol.
Fuel	Unleaded regular gasoline (leaded acceptable substitute)				Do not use gasoline containing more than 10% ethanol; do not use methanol-containing gasoline
Fuel	LP gas (liquefied petroleum gas)	Vapor withdrawal type fuel system	-29°C to 0°C		Propane vaporizes as low as -20 degF (-29 degC); butane returns to liquid below about 32 degF (0 degC). Higher propane ratio desired below freezing
Other	Battery electrolyte - dilute sulfuric acid				Fill unsealed batteries with distilled water only; do not use tap water
Other	Bicarbonate of soda solution			1.0 pound (500 grams) per 1 gallon (4 liters) of water	Electrolyte neutralizing agent
Other	Distilled water				For battery cells only; DO NOT USE TAP WATER IN BATTERY

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

Setting Spark Plug Gap adjustment

⚠ DO NOT BLAST CLEAN SPARK PLUGS.

⚠ Sparking can occur if wire terminals do not fit firmly over spark plug terminal ends.

Tools: Feeler gauge

Clean spark plugs by scraping or wire brushing and washing with commercial solvent.
Reset gap to 0.030 inch (0.8mm) using a feeler gauge.

Battery Cable Connections installation

⚠ Verify the battery cable boot for the starter cable has been installed.

⚠ Damage will result if the battery connections are made in reverse.

Connect the battery cable from the POSITIVE, POS or (+) post to the lug on the starter contactor.
Connect the battery cable from the NEGATIVE, NEG or (-) post to the frame ground connection.
Connect cables so the connectors are clean and tight.

Initial Start (Post Installation) installation

⚠ Correct any leakage immediately before proceeding.

Turn off all electrical loads by setting the generator's main circuit breakers to OFF.
Crank and start the engine; more cranking may be required to prime the fuel lines.
Let the engine warm up about five minutes to stabilize internal temperatures.
Inspect the engine/generator for fuel, oil and exhaust system leaks; correct any leakage immediately.
When no-load tests are complete, apply electrical loads and check operation under load; run at least 30 minutes.
Turn off all electrical loads by setting the main circuit breakers to OFF.
Let the unit run at no-load a few minutes, then shut down the engine.

Testing Under Load installation

⚠ You must not allow the unit to overheat during prolonged operation.

Apply electrical loads equal to about 75 to 100 percent of the unit's rated wattage/amperage capacity.
Let the unit run at least 30 minutes with load applied.
Check that the unit is not running excessively hot and that adequate cooling airflow is available.

Testing the LP Gas System for Leaks installation

⚠ DO NOT USE ANY FLAME TO TEST FOR LEAKS.

⚠ Gaseous fuel lines between tank and secondary regulator are under positive pressure; outlet side of secondary regulator is negative pressure and can draw flame into a line or fitting causing an explosion.

Tools: Soap and water solution

Obtain a separate source of 12 volts DC to open the gaseous fuel solenoid valve.
Test all connections, hoses, valve regulators, fittings and other fuel system parts.
Test under gas or air pressure of not less than 90 psi (620 kPa).
Use soap and water or an equivalent solution to check for leaks.
Do not place the generator into service until the system is properly tested.

25-Hour Check Up maintenance

After 25-hour break-in period, contact authorized service facility for maintenance.
Change engine crankcase oil and oil filter.
Check all fluid levels.
Inspect cooling and ventilation openings on vehicle.
Check engine carburetor adjustments.
Check engine ignition system.
Inspect entire electrical system.
Inspect engine exhaust system.

Battery maintenance

⚠ DO NOT USE TAP WATER IN BATTERY.

⚠ STORAGE BATTERIES GIVE OFF EXPLOSIVE HYDROGEN GAS.

Tools: hydrometer

Once weekly: Inspect battery posts and cables for tightness, corrosion. Clean and/or tighten as needed.
Check battery fluid level; if necessary, fill with DISTILLED WATER ONLY. DO NOT USE TAP WATER.
Every six months: Have battery state of charge and condition checked by automotive service facility with hydrometer.

Battery Inspection maintenance

⚠ Storage batteries give off explosive hydrogen gas.

⚠ Battery electrolyte is caustic sulfuric acid; wear protective goggles, clothing and gloves.

Tools: hydrometer, distilled water

Once weekly, inspect battery posts and cables for tightness and corrosion.
Clean and/or tighten as needed.
Check battery fluid level and fill with distilled water only.
Do not use tap water in the battery.
Every six months have state of charge and condition checked by an automotive service facility.

Battery Inspection and Service maintenance

⚠ Storage batteries give off explosive hydrogen gas

⚠ Battery electrolyte is caustic sulfuric acid

Tools: Automotive type battery hydrometer

Once weekly inspect battery posts and cables for tightness and corrosion.
Clean and/or tighten as necessary.
Check battery fluid level and fill with distilled water only.
Every six months have state of charge and condition checked with an automotive hydrometer.

Change Engine Oil maintenance

Tools: suitable container

Warm up engine for at least five minutes, then shut down.
With engine still warm, remove cap from oil drain hose and drain oil completely into a suitable container.
When oil has drained, install and tighten drain hose cap.
Remove oil dipstick and fill crankcase with recommended oil; crankcase holds about 1.4 liters.
Do not fill above FULL mark; install and tighten dipstick cap before operating.

Change Oil Filter maintenance

⚠ Filter will retain some oil

Turn oil filter counterclockwise to remove.
Coat gasket of new filter with engine oil.
Turn new filter clockwise until gasket contacts filter adapter, then tighten an additional 3/4 to one turn by hand.
Run engine and check for leaks.
Check oil level and fill to full mark after checking for leaks.

Changing Engine Oil maintenance

⚠ DO NOT OVERFILL ABOVE FULL MARK

Warm up engine at least five minutes, then shut down.
With engine still warm, remove oil drain plug and drain oil completely.
Install and tighten oil drain plug.
Remove oil dipstick and fill crankcase with recommended oil.
Install and tighten dipstick cap before operating engine.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Voltage reconnection

Voltage	Phase	Connection	Leads	Notes
		Grounding/bonding	Bonding conductor; No. 8 AWG copper wire minimum	Ground generator by solid mounting to vehicle frame/chassis or by approved bonding conductor. DO NOT disconnect bonding conductor. If replaced, use only flexible No. 8 AWG copper wire minimum.
		Isolation of power sources	Junction box to double-pole, double-throw transfer switch or approved isolation receptacle	Must prevent vehicle electrical circuits from being connected to two different power supplies at the same time (generator and dockside power). Generator AC connection system uses a GROUNDED neutral; a separate green ground wire connects to the vehicle junction box.
120	1	120 V only - dual stator windings connected in parallel	T1 (red) and T3 (black) hot; T2 (white) grounded neutral; green ground wire	Line T1 to T2 protected by 30-amp circuit breaker CB1; line T3 to T2 protected by 30-amp circuit breaker CB2. Maximum current 58.3 A (70G) or 55.0 A (70LP) at 120 V.
120	1	120 VAC loads only	T1(Red)-T2(White) or T3(Black)-T2(White)	Grounded neutral, dual stator AC power windings
120	1	Connection for 120 Volts Only (Figure 1)	Dual stator power windings; grounded neutral; CB1	These air-cooled Q Series generator sets are equipped with dual stator AC power windings supplying power by a dual 2-wire connection system.
120	1	Dual 2-wire connection system	T1, T2, T3, T4; BLACK, WHITE, GROUNDED NEUTRAL	Connection for 120 volts only (Figure 1)
120	1	Dual 2-wire connection system (120 volts only)	Dual stator power windings; grounded neutral	Figure 1 — Connection for 120 Volts Only; jumper between circuit breakers must be removed when connecting for 120/240 volts
120	1	Loads across T1 (red) to T2 (white) and T3 (black) to T2 (white)	T1 (red), T2 (white), T3 (black)	Must not exceed 58.3 amps for PRIMEPACT 70G or 55 amps for PRIMEPACT 70LP with 120 V across each set of terminals. Do NOT connect loads in excess of circuit breaker ratings.
120	single	120 VAC loads only	T1 (red) and T3 (black) hot, T2 (white) grounded neutral	Max total wattage equal to generator's rated power output, 120V across output terminals
120	single	120 volts only — dual 2-wire connection with jumper between circuit breakers installed		Figure 1 connection for 120 volts only; grounded neutral
120 volts only	1	jumper installed between circuit breakers	T1/T2/T3/T4, neutral	stator dual 2-wire connection system
120 volts only	single	jumper wire installed between circuit breakers for 120/240V reconnection	T1/T2/T3/T4, grounded neutral	dual stator AC power windings, dual 2-wire connection system; neutral grounded
120/240	1	120/240 VAC loads	T1(Red)-T2(White)-T3(Black)	One 240V load, or two 120V loads each up to half rated wattage
120/240	1	Dual voltage reconnection		Remove jumper between circuit breakers when connecting for 120/240 volts. Units are not listed per RVIA/ANSI when reconnected for dual voltage output.
120/240	1	Reconnectable dual voltage output	Dual stator power windings	All units are reconnectable to 120 and/or 240 volts, dual voltage output; units are not listed per RVIA/ANSI when reconnected for dual voltage output
120/240	1	Reconnected for dual voltage AC output	Dual stator power windings	Be sure to remove the jumper between the circuit breakers when connecting for 120/240 volts. If reconnected for dual voltage, the unit is no longer RVIA listed.
120/240	single	120/240 VAC loads	T1 (red), T2 (white), T3 (black); dual stator AC power windings	One load at 240V full rated output, or two separate 120V loads each up to half rated output; T1-T2 protected by 30A CB1, T3-T2 protected by 30A CB2 (20A CB2 on some models)
120/240	single	Dual voltage output — remove the jumper between the circuit breakers		Units are not listed per RVIA/ANSI when reconnected for dual voltage output; replacement line breakers consist of two separate breakers with a connecting piece between handles
230	Single	Dual two-wire connection system, neutral grounded (Figure 1.1 — Connections for 230 Volts Only)		Dual stator AC power windings; two 30-amp circuit breakers. If reconnected for dual voltage AC output (115/230 volts), replacement line breakers consist of two separate breakers with a connecting piece between the handles.
230	Single	Dual two-wire connection system; neutral is grounded; one side of the winding is grounded	T1 (red) 'hot', T3 (black), green ground wire	Dual stator AC power windings; solid-state voltage regulator connected across 1/2 of the output winding, regulating at 115 volts when AC frequency is 50 Hertz
240	1	120/240 V dual voltage output	T1 (red), T2 (white), T3 (black), green ground wire	All units are reconnectable to 120 and/or 240 volts, dual voltage output. Units are not listed per RVIA/ANSI when reconnected for dual voltage output. Rated maximum continuous current at 240 volts is 29.2 amps (70G) or 27.5 amps (70LP).

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Parts cataloged across the Generac GN-480 family

252

Part #	Description	Category
069341	FOAM PRE-CLEANER	air_filter
073123	AIR FILTER (NOT SHOWN)	air_filter
073131	AIR CLEANER SUPPORT BRACKET	air_filter
0C2338A	AIR CLEANER DECAL-PRIMEPACT 55LP	air_filter
0C2338C	AIR CLEANER DECAL-PRIMEPACT 66LP	air_filter
0C2338E	AIR CLEANER DECAL-PRIMEPACT 70LP	air_filter
69341	Foam Pre-cleaner	air_filter
73123	Air Filter	air_filter
083049	REGULATOR VOLTAGE	avr
83049	Voltage Regulator	avr
075216	BELT (POLY V 4L)-40"	belt
42633	BELT (POLY V 4L)-40"	belt
75216	40" Poly Vinyl 4L Belt	belt
066386	BRUSH HOLDER	brush
490316	Brush Set Spring	brush
66386	BRUSH HOLDER	brush
75257	Brush Assembly	brush
80011	Brush Set Spring	brush
55162	PIPE SEALANT	fluid
072375	FILTER, FUEL	fuel_filter
087769	FUEL FILTER	fuel_filter
87769	FUEL FILTER	fuel_filter
87789	Fuel Filter	fuel_filter
066480	AIR CLEANER GASKET	gasket
067158	INTAKE MANIFOLD GASKET	gasket
067895	INTAKE MANIFOLD GASKET	gasket
067897	EXHAUST GASKET (NOT SHOWN)	gasket
067920	VALVE COVER GASKET	gasket
068548	GASKET, OIL FILTER ADAPTER	gasket
069325	OIL SUMP GASKET	gasket
069332	CYLINDER HEAD GASKET	gasket
069336	OIL SUMP GASKET	gasket
069379	CARBURETOR MOUNTING GASKET	gasket
070594	CARBURETOR MOUNTING GASKET	gasket
072315	BREATHER GASKET	gasket
072383	GASKET, COLLECTOR PAN	gasket
075229	SLIDE PAN, GASKET	gasket
075258	ENGINE GASKET KIT	gasket
077643	GASKET, EXHAUST OUTLET	gasket
091481	GASKET AND CAP ASSEMBLY	gasket
0A5508	OIL FILL TUBE GASKET	gasket
66480	Air Cleaner Gasket	gasket
67895	GASKET, INTAKE MANIFOLD	gasket
67897	Exhaust Gasket	gasket
67920	Valve Cover Gasket	gasket
68548	Oil Pad Gasket	gasket
69332	Cylinder Head Gasket	gasket
69336	GASKET, OIL SUMP	gasket
69379	Carburetor Mounting Gasket	gasket
72315	GASKET, BREATHER	gasket
72383	Collector Pan Gasket	gasket
73174	GASKET, EXHAUST MANIFOLD	gasket
75209	GASKET, EXHAUST MANIFOLD	gasket
75224B	GASKET, COLLECTOR PAN	gasket
75229	Slide Pan Gasket	gasket
75258	Engine Gasket Kit	gasket
77114	Exhaust Outlet Gasket	gasket
77643	Exhaust Outlet Gasket	gasket
78229	SLIDE PAN, GASKET	gasket
78631	GASKET, CARBURETOR/SKIRT	gasket
79678	Exhaust Manifold Gasket	gasket
87895	Intake Manifold Gasket	gasket
89965	Cylinder Head Gasket	gasket
91481	Gasket and Cap Assembly	gasket
A5508	OIL FILL TUBE GASKET	gasket
030340	HOSE ¼ ID	hose
047290	HOSE 3/8 ID SINGLE BRAID (16” LG)	hose
057822	CLAMP HOSE #8 .53-1.00	hose
070596	BREATHER TUBE	hose
070597	AIR INLET TUBE	hose
074994	HOSE 1\2 ID	hose
087770	FUEL LINE	hose
30340	1/4" FUEL LINE (8" LONG)	hose
47662-T	4-1/2" long Fuel Hose	hose
70596	Breather Tube	hose
70597	Air Inlet Tube	hose
74950	TUBE, OUTER OIL	hose
74951	TUBE, INNER OIL	hose
74994	1/2" I.D. x 10" LONG HOSE	hose
75710-A	Oil Fill and Drain Tube	hose
75710A	TUBE, OIL FILL AND DRAIN	hose
87770	5/16" dia. Fuel Line	hose
070185	Oil Filter	oil_filter
70185	FILTER, OIL	oil_filter
70536	Oil Screen	oil_filter
022097	WASHER LOCK M6-1/4	other_service
022676	FUSE AGC-15A.	other_service
026307	ELBOW 90 DEG STREET 3/4	other_service
026915	NIPPLE CLOSE 3/4 X 1.375	other_service
028739	4" LONG TIE WRAP	other_service
037398	HEX LOCK NUT (NYLON)	other_service
038750	M6-1.0 X 30MM HEX HD. CAPSCR.	other_service
047227	GOVERNOR ADJUSTER SCREW	other_service
047411	SCREW HHC M6-1.0 X 16 G8.8	other_service
049451	WASHER FLAT .406ID X 1.62OD	other_service
049813	NUT HEX M6 X 1.0 G8 YEL CHR	other_service
055162	PIPE SEALANT	other_service
056893	#10-24 X 1/2 SCREW	other_service
061696	BARBED 90 DEG. 3/8 X 1/2	other_service
065795	BATTERY CHARGER RECTIFIER	other_service
066476	M6-1.0 X 12MM HEX SCREW W/LOCK WASHER	other_service
067813	VALVE GUIDE	other_service
067891	IGNITION COIL	other_service
067910	INTAKE VALVE SEAT	other_service
069316	EXHAUST VALVE	other_service
069317	INTAKE VALVE	other_service
069327	PISTON LOCKING RING	other_service
069333	SLEEVE BEARING	other_service
070108	GOVERNOR-TO-CARBURETOR ROD	other_service
070125	ANTI-LASH SPRING	other_service
070155	GOVERNOR LEVER	other_service
070535	OIL SCREEN	other_service
072366	COTTER PIN (governor)	other_service
073112B	Carburetor Assembly	other_service
074961	GOVERNOR ADJUSTER BRACKET	other_service
074962C	GOVERNOR SPRING (PP55G/LP, PP66G/LP)	other_service
074962G	GOVERNOR SPRING (PP70G/LP, Q70G)	other_service
075211	GASEOUS FUEL REGULATOR	other_service
075248	STANDARD PISTON ASSEMBLY	other_service
075249	STANDARD PISTON RING SET	other_service
075252	KIT, CARBURETOR OVERHAUL-NOT SHOWN	other_service
075271	VALVE OVERHAUL KIT	other_service
075944	GOVERNOR SPRING BRACKET	other_service
076242	1/8 I.D. X 1/8 RIVET	other_service
089473	BI-METAL ASSEMBLY, CHOKE	other_service
089870	Solenoid, Fuel Shutoff (Q-70G Only)	other_service
091306	SOLENOID, CHOKE	other_service
0A1662A	CARB. V-TWIN L/P	other_service
0A2666	GASEOUS FUEL SOLENOID	other_service
0A5198	REGULATOR MOUNTING BRACKET	other_service
0A5606	ELBOW 90 DEG 3/8 X 3/4	other_service
0A7782A	FLYWHEEL ASSEMBLY	other_service
22676	15 Amp Fuse	other_service
22876	FUSE AGC-15A.	other_service
31971	BALL BEARING	other_service
38077	CIRCUIT BREAKER 15A.	other_service
53623	2.5A Circuit Breaker	other_service
54502	3A Circuit Breaker	other_service
56739	Starter Contactor	other_service
65795	Battery Charge Rectifier	other_service
66443B	Vibration Mount	other_service
67888	3/8" NPT Oil Drain Plug	other_service
67891	Ignition Armature Assembly	other_service
67910	Intake Valve Seat	other_service
69316	Exhaust Valve	other_service
69317	Intake Valve	other_service
69333	Sleeve Bearing	other_service
70199	Breather Baffle	other_service
70530	Camshaft Assembly	other_service
70535	Oil Screen	other_service
70584	Valve Tappet	other_service
72301	Breather Assembly	other_service
72361	Governor Shaft Bushing	other_service
72362	Governor Shaft Bushing	other_service
72379B	Bearing Carrier, Upper	other_service
73106B	Pulley, Alternater	other_service
73112B	Carburetor Assembly	other_service
73130	Flywheel	other_service
73159	BALL BEARING	other_service
75211	GASEOUS FUEL REGULATOR	other_service
75234	RESISTER, 1 OHM 25W 42 A9947B 1 45A CIRCUIT BREAKER (10KW)	other_service
75244	Remote Cable Assembly	other_service
75249	Standard Piston Ring Set	other_service
75252	Carburetor Overhaul Kit	other_service
75261	Clutch Assembly	other_service
75269	Armature Assembly	other_service
75271	Valve Overhaul Kit	other_service
75995	Bearing Carrier, Lower	other_service
76271	VALVE OVERHAUL KIT	other_service
77004-G	Rotor Assembly	other_service
77005H	Rotor	other_service
80095H	ROTOR ASSEMBLY	other_service
81190	LP HOOK-UP FITTING	other_service
82081	C/BREAKER 30A.	other_service
86731A	ASSEMBLY, MUFFLER	other_service
87798	Start/Stop Switch	other_service
87844H	Stator	other_service
87845-G	Stator Assembly	other_service
89473	Bimetal Choke Assembly	other_service
89680	SPARK ARRESTOR	other_service
89870	Fuel Solenoid Shutoff (Q70)	other_service
90144	20A Circuit Breaker	other_service
90145	30A Circuit Breaker (all units); 30A Circuit Breaker Q-70G	other_service
91306	Choke Solenoid	other_service
91480	Rocker Arm and Cover	other_service
92113	dk a_i Dh ok	other_service
92234	RV CONTROL BOARD	other_service
92848H	STATOR ASSEMBLY	other_service
97939	Battery Charge Rectifier	other_service
A1662A	Carburetor	other_service
A2666	GASEOUS FUEL SOLENOID	other_service
A4008	LP Regulator	other_service
A5892	Magnetic Housing Ass'y	other_service
A9178	Ignition Assembly	other_service
070547	OIL PUMP ASSEMBLY	pump
090475	FUEL PUMP	pump
70547	OIL PUMP ASSEMBLY	pump
90475	FUEL PUMP	pump
067805	OIL SEAL	seal
067866A	O-RING	seal
067871	O-RING, CAP	seal
067888	OIL SEAL ASSEMBLY	seal
067924	OIL SEAL	seal
068554A	GOVERNOR SHAFT SEAL	seal
068573	OIL PUMP O-RING	seal
070122	VALVE STEM SEAL	seal
070169	SEALING WASHER	seal
070506	OIL GALLEY O-RING	seal
075253	WASHER VALVE COVER SEAL	seal
079678	RING, SEALING	seal
22717-A	Rubber Grommet	seal
22717-B	Rubber Grommet	seal
67805	OIL SEAL-30 DIAMETER	seal
67866	O-RING	seal
67866A	O-RING	seal
67871	O-RING, CAP	seal
67911	SEAL, VALVE STEM	seal
67924	OIL SEAL-35 DIAMETER	seal
68554	Governor Shaft Seal	seal
68554A	GOVERNOR SHAFT SEAL	seal
68573	O-RING, OIL PUMP	seal
70122	Valve Stem Seal	seal
70169	Sealing Washer	seal
70189	Sealing Washer	seal
70506	O-RING, OIL GALLEY	seal
7512-4	O-ring Drain	seal
75253	Washer Valve Cover Seal	seal
75262	SEAL, BREATHER SCREW	seal
75263	SEAL, BREATHER SCREW	seal
75711	O-ring Adaptor	seal
75712	O-ring Drain	seal
074948	10 PSI-SWITCH, OIL PRESSURE	sensor
074950	SWITCH, HIGH TEMPERATURE	sensor
075281	SWITCH, HIGH TEMPERATURE	sensor
0A8584	SWITCH OIL PRESSURE	sensor
60108	GASKET, OIL FILTER SUPPORT	sensor
74027	SWITCH, HIGH TEMP.	sensor
75281	High Temperature Switch	sensor
77667	Oil Pressure Switch	sensor
A8584	SWITCH-OIL PRESSURE	sensor
072347	SPARK PLUG	spark_plug
075272	SPARK PLUG TERMINAL	spark_plug
72347	SPARK PLUG-CHAMPION R12YC	spark_plug
73132	Spark Plug Boot	spark_plug
75272	Spark Plug Terminal	spark_plug
0C2881	STARTER MOTOR (NOT SHOWN)	starter
0D1227	CONTACTOR, STARTER	starter
75255	Starter Motor	starter
75260	Starter Drive Assembly	starter
86729	Contactor, Starter	starter
99948	STARTER MOTOR	starter
C2881	STARTER MOTOR (NOT SHOWN)	starter

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Common questions

What is the oil capacity of the Generac GN-480?

The Generac GN-480 engine has an oil capacity of 1.7 liters.

What is the displacement of the Generac GN-480?

The Generac GN-480 has a displacement of 0.48 liters with 2 cylinders.

Which generators use the Generac GN-480 engine?

The Generac GN-480 powers 12 generator set(s), including Generac NP-66G, Generac NP-66LPG, Generac PP50G, Generac PP70G, Generac PRIMEPACT 55G.

How often should you change the oil in the Generac GN-480?

The Generac GN-480 oil change interval is every 100 hours.

What is a common problem with the Generac GN-480 engine?

A commonly reported issue on generators using the Generac GN-480 is: Engine won't crank.. Cause: 1. 15 amp fuse blown. 2. Loose, or corroded or defective battery cable(s). 3. Battery is discharged or defective. 4. Defective starter contactor. 5. Defective starter motor. 6. Defective Start/Stop switch.. Fix: 1. Replace blown fuse. 2. Tighten, clean or replace, as necessary. 3. Recharge or replace battery. 4. Replace starter contactor. 5. Replace starter motor. 6. Replace switch..