HomeCummins/OnanCummins/Onan 4000

Cummins/Onan 4000 Generator Set

The Cummins/Onan 4000 is a 4 kW standby generator set powered by a Cummins/Onan EM (SN5782U1G2RA) engine. It holds about 3.3 L (0.9 gal) of oil.

4 kW
Standby
782.0 L
Displacement
3.3 L
Oil capacity
0
Document types

How to read your Cummins/Onan serial & model number →

Service parts for the 4000

Grouped by system, with how many of each the parts manual calls for.

Air intake

1 required
N16SBAir filtersee priceAmazon

Fuel system

1 required
FF5039Fuel filter$26.99eBay

Prices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.

Specifications

Standby power4 kW
Oil capacity3.3 L

Engine

Cummins/Onan EM (SN5782U1G2RA)
Oil capacity3.3 L
Displacement782.0 L
Rated speed1800 rpm

Maintenance & consumables

for the Cummins/Onan EM (SN5782U1G2RA)
ItemSpecCapacityPart #Interval
Air filterBreaker Ampere Rating 1600AN16SB Amazon eBay
Fuel filterFuel, Spin-OnFF5039 Amazon $78.00 eBay $26.99
Oil filter150 hr
Battery150 hr
Belt
Coolant
Oil3.5 quarts50 hr
Spark plug300 hr

Common questions

What size generator is the Cummins/Onan 4000?

The Cummins/Onan 4000 is rated 4 kW standby.

What engine does the Cummins/Onan 4000 use?

The Cummins/Onan 4000 is powered by the Cummins/Onan EM (SN5782U1G2RA) engine.

What's the oil capacity on a Cummins/Onan 4000?

The Cummins/Onan EM (SN5782U1G2RA) engine in the Cummins/Onan 4000 has an oil capacity of 3.3 liters.

What fuel filter does the Cummins/Onan 4000 use?

The Cummins/Onan 4000 uses fuel filter part number FF5039.

What air filter fits the Cummins/Onan 4000?

The Cummins/Onan 4000 uses air filter part number N16SB.

Troubleshooting

6

Symptoms & remedies

SymptomRemedy
The engine fails to crank.A. Try starting at the genset rather than at the remote control. b. Replace fuse F1 on the control panel if it has blown. c. Clean and tighten the positive (+) and negative (-) battery cable connections at the battery and the genset. d. Recharge the battery. Refer to the battery manufacturer's recommendations.
The engine cranks slowly.A. Disconnect the air conditioner and other large loads. b. Clean and tighten the positive (+) and negative (-) battery cable connections at the battery and the genset. c. Recharge the battery. Refer to the battery manufacturer's recommendations. d. Change the engine oil to oil having the proper viscosity for the ambient temperature. See Table 1.
The engine cranks but fails to start.A. Check the fuel tank and fill if necessary. b. Open any closed fuel shut off valve. c. Check engine oil level and add oil as necessary. d. Replace fuse F2 (side of control panel) if it has blown. e. Service the air cleaner. f. Secure the spark plug leads on the spark plugs. g. Replace the spark plugs.
The engine runs and then stops or surges.A. Check the fuel tank and fill if necessary. b. Check the engine oil level and add oil as necessary. Drain excess oil if the level is above the dipstick Full mark. c. Check and reset the carburetor preheater lever and altitude adjust knob. See Varying Weather and Altitude. d. Secure the spark plug leads on the spark plugs. e. Replace the spark plugs.
There is no electrical power even though the genset runs.A. Reset tripped circuit breakers. See Powering Equipment. b. Unless there is an automatic power transfer switch, plug the boat power cord into the genset power output receptacle (if so equipped) or turn the pontoon boat power selector switch to its genset position (if so equipped).
The remote battery condition meter indicates low voltage.A. Clean and tighten the positive (+) and negative (-) battery cable connections at the battery and the genset. b. Recharge the battery. Refer to the battery manufacturer's recommendations.

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing. Full Cummins/Onan 4000 troubleshooting guide (8 entries) →

Parts

70
Part #DescriptionQtySystem
015-0074Steering Wheel Mounting Disk (Rubber)1Steering wheel mounting disk Amazon eBay
050-0030Steering Wheel1Steering wheel Amazon eBay
103-0810Gasket, Mounting - Gearcase1Gasket Amazon eBay
122-0320Adapter, Oil Filter1Oil filter Amazon Amazon eBay eBay
122-0360Drain, Oil Filter (Unpainted/Painted)1Oil filter Amazon eBay
122-0645Oil Filter1Oil filter Amazon $14.11 eBay $11.99
122-0774Filter, Oil1Oil filter Amazon eBay $12.48
140-1087Gasket, Horn - Air3Gasket Amazon eBay
149-1994Pump, Fuel - Electric (Serial F860825839-F863114065)1Pump Amazon eBay
149-2110Pump, Fuel - Electric (Begin F860825893)1Pump Amazon eBay
153-0554Element, Thermostat1Thermostat Amazon eBay
191-1599Starter, 12 Volt Motor (Spec A)1Starter Amazon eBay
191-1667Starter, 12 Volt Motor (Begin Spec B)1Starter Amazon eBay
509-0040Seal, Oil - Crankshaft1Seal Amazon eBay $9.95
AMC5NN8286DRadiator Hose, LowerHose Amazon eBay
AMP192-DBGVCCReman Injection PumpPump Amazon eBay
AMP4000-DPAReman Injection PumpPump Amazon eBay
AN500T0122STARTER MOTOR - Aftermarket ManufactureStarter Amazon eBay
AN500T0127STARTER MOTORStarter Amazon eBay
FF5039Fuel, Spin-OnFuel filter Amazon $78.00 eBay $26.99
M-1604-9Spark Plug (Gasoline)1Spark plug Amazon eBay
N16SBBreaker Ampere Rating 1600AAir filter Amazon eBay
SN5782U1G2RANAMEPLATE1Nameplate Amazon eBay
101-0450Screw, Cap - Hex Head 3/8-16 x 1-1/4"1Service part / kit Amazon eBay FridayParts $799.90
103-0772Gearcase1Service part / kit Amazon eBay
110-0197Insert, Valve Seat - Intake2Service part / kit Amazon eBay $27.99
110-1824Bearing, Crankshaft - Rear (Standard .002" .010" .020" .030" Undersize)1Service part / kit Amazon eBay
110-1879-01Washer, Lock (3/8")1Service part / kit Amazon eBay
110-3527Insert, Valve Seat - Exhaust2Service part / kit Amazon eBay
113-0189Ring, Retaining - Piston (Standard .005" .010" .020" .030" .040" Oversize)2Service part / kit Amazon eBay $49.99
114-0240Rod, Connecting (Standard .010" .020" .030" Undersize)4Service part / kit Amazon eBay
114-0257Ring Set, Piston (Standard .010" .020" .030" Undersize)2Service part / kit Amazon eBay
123-1174Spring, Breather Valve1Service part / kit Amazon eBay
123-1175Reed, Breather Valve1Service part / kit Amazon eBay
140-1891Element, Cleaner - Air21Service part / kit Amazon eBay $11.55
140-1894Housing, Cleaner - Air1Service part / kit Amazon eBay
150-1187Screw, Machine - Pan Head (#8-32 x 3/8")2Service part / kit Amazon eBay
153-0555Housing Assembly, Choke1Service part / kit Amazon eBay
153-0556Bracket, Mounting - Diaphragm1Service part / kit Amazon eBay
153-0563Clip, U' - Diaphragm Mounting2Service part / kit Amazon eBay
153-0567Bi-Metal, Choke11Service part / kit Amazon eBay
154-2447Manifold, Intake1Service part / kit Amazon eBay
166-0747Clamp, Coil3Service part / kit Amazon eBay
166-0772Coil, Ignition1Service part / kit Amazon eBay
167-1605-02Cable, Plug - Spark (135" Boot, Spec A-C)1Service part / kit Amazon eBay
167-1615-01Cable, Spark Plug 9'1Service part / kit Amazon eBay
212000Fax: 0044 (0) 1743 212700Service part / kit Amazon eBay
223141Fax: 0044 (0) 1785 215110Service part / kit Amazon eBay
226-2980Switch, Low Oil Pressure10Service part / kit Amazon eBay
300-2784Emerald Control BoardService part / kit eBay
300-3056/3687Emerald Control BoardService part / kit buy
300-3763-01Emerald/Marquis Control BoardService part / kit eBay
300-3950Control Board Replacement Kit1Service part / kit eBay
312-0249Condenser, Ignition6Service part / kit Amazon eBay $63.34
323-1486SocketsService part / kit Amazon eBay
323-1487-04Onan 16-Socket ConnectorService part / kit Amazon eBay
420-0572Control board testerService part / kit eBay
516-01412 "Pin, Gear Cover Locating1Service part / kit Amazon eBay
564625Fax: 0039 (0) 31 565480/564145/396001Service part / kit Amazon eBay
582240Perkins Engines Company LimitedService part / kit Amazon eBay
583000Telex: 32501 Perken G1Service part / kit Amazon eBay
610181Service part / kit Amazon eBay
610182Service part / kit Amazon eBay
815-0590Screw, Hex Head (Special)10Service part / kit Amazon eBay
850-0050Washer, Lock - Spring (3/8”)4Service part / kit Amazon eBay
870-0302Nut, Self-Locking (5/16-24)28Service part / kit Amazon eBay
A30816Fax: 0061 (0) 597 1305Service part / kit Amazon eBay
M-1604-11/4 in. barb fitting1Service part / kit Amazon eBay
M-1604-14Governor Adjustment1Service part / kit Amazon eBay
M1604BGE AND BGEL GENERATOR SETSService part / kit Amazon eBay

Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.

Fuel consumption

RatingLoadL/hgal/h
Prime0.62.3
Standby0.41.5

Available documents

Full service, cheapest listings

Priced items from this model's own parts manual.

Fuel filter FF5039$26.99
1 priced item$26.99
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