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Home›Cummins/Onan›Cummins/Onan 4BT 3.9

Cummins/Onan 4BT 3.9 Generator Set

The Cummins/Onan 4BT 3.9 is a 5 kW standby generator set powered by a Cummins/Onan 4BT3.9 engine. It holds 17.7 L (4.7 gal) of coolant.

5 kW
Standby
3.9 L
Displacement
2
Document types

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

Specifications

Standby power5 kW

Engine

Cummins/Onan 4BT3.9
Coolant capacity17.7 L
Displacement3.9 L

Maintenance & consumables

for the Cummins/Onan 4BT3.9
ItemSpecCapacityPart #Interval
Oil—

Common questions

What is the power rating of the Cummins/Onan 4BT 3.9?

The Cummins/Onan 4BT 3.9 is rated 5 kW standby.

What engine does the Cummins/Onan 4BT 3.9 use?

The Cummins/Onan 4BT 3.9 is powered by the Cummins/Onan 4BT3.9 engine.

Parts

117
Part #DescriptionQtySystem
102-1147Gasket, Drain - Oil PanGasket PartsGeek
140-2164Nut, Square (1/4-20)1Nut PartsGeek kuduparts $10.00
150-2007Guard. Belt Screw. Cap - Hex Head (1/2-13 X 2-1/4“)Belt PartsGeek FridayParts $263.79
150-2201Sensor, Speed – MagneticSensor PartsGeek
187-0001Pump, WaterPump PartsGeek
187-0002Gasket Kit, End - TopGasket PartsGeek
187-0008Belt, Drive4Belt PartsGeek
187-0009Thermostat4Thermostat PartsGeek
187-0010Gasket, ThermostatThermostat PartsGeek
187-0012Gasket, Cover - Valve1Gasket Amazon eBay PartsGeek
187-0013Pump, Transfer - FuelPump Amazon eBay PartsGeek
187-0020Pump, Injection1Pump PartsGeek
193-0244Sender, Oil Pressure (E1)Sensor PartsGeek
193-0353Sender, Temperature - OilSensor PartsGeek
193-0375# Sender, Water TemperatureSensor PartsGeek
309-0269Air Cleaner (Includes Element) - Standard1Switch PartsGeek ironwing $32.86
309-0272Air Cleaner - Heavy Duty (10" Inlet Tube)Air filter PartsGeek
309-0561Switch, Temperature - Washer, Lock (#10)1Switch PartsGeek
323-1200Resistor, Fixed, Wirewound AR4Resistor PartsGeek
323-1306Screw, Cap - Hex Head (1/4-20 x 1/2")1Screw PartsGeek
332-0051Clip, Wire - Fuel Hose---—Hose PartsGeek
332-2921Switch, Temperature - Washer, Lock (M8)1Switch PartsGeek
353-0094-01Connector Housing and Contact Pins, 8 Pin (Less Pins)1Connector PartsGeek
405-3826-01Support, Engine - Screw, Cap - Hex Head (M12 x 1.75 x 65mm)1Support PartsGeek
503-0098Hose, Oil Drain - Bulk (3/4Hose PartsGeek
503-0183Clamp, HoseHose PartsGeek
503-0365Heater, Engine - 750 Watt (120 volt)1Heater PartsGeek
503-0685Clamp, HoseHose PartsGeek
505-0104Air filter PartsGeek
526-0018Gasket, Flange (1-3/4)Gasket PartsGeek FridayParts $1002.50
750-1010Screw, Machine - Fillister Head (1/4-20 x 1")1Screw PartsGeek
800-0048Screw, Cap - Hex Head (3/8 - 16 X 3/4")1Screw PartsGeek
821-0018Thermostat (Includes Plugs)4Thermostat PartsGeek
102-1237Adapter, Oil Drain (Ml8 x 1/2") (S2)Service part / kit PartsGeek
145-0596Service part / kit PartsGeek
150-2187Lever, Actuator - GovernorService part / kit PartsGeek
150-2203Service part / kit PartsGeek
150-2218Service part / kit PartsGeek
150-2251Joint, BallService part / kit PartsGeek
151-0611Control, GovernorService part / kit PartsGeek FridayParts $249.00
151-0632Service part / kit PartsGeek FridayParts $315.00
154-2581Service part / kit PartsGeek
155-2062Service part / kit PartsGeek
155-2080Service part / kit PartsGeek
155-2175Clamp, Muffler 4"Service part / kit PartsGeek
155-2256Service part / kit PartsGeek
155-2353Service part / kit PartsGeek
187-0004Service part / kit PartsGeek
187-0007Service part / kit PartsGeek
187-0011Filter, Fuel1Service part / kit PartsGeek
187-0015Filter, Oil1Service part / kit Amazon eBay $39.95 PartsGeek
187-0017Service part / kit Amazon eBay $44.71 PartsGeek
187-0018Service part / kit PartsGeek
187-0146Service part / kit PartsGeek
187-0198Service part / kit PartsGeek
309-0553Service part / kit PartsGeek
309-0554Service part / kit PartsGeek
323-1304tiotming, UmectorService part / kit PartsGeek
332-0325Service part / kit PartsGeek
332-0941Service part / kit PartsGeek
332-1087Service part / kit PartsGeek
332-1279Harness. Wiring (Includes Cable Ties and Terminals)Service part / kit PartsGeek
332-1445Tie. CableService part / kit PartsGeek
332-2739BracketService part / kit PartsGeek
333-0291Service part / kit PartsGeek
333-0292Service part / kit PartsGeek
353-0094Service part / kit PartsGeek
357-0030RECTIFIER ‘BATT CHARGINGService part / kit PartsGeek
416-0446Cable, Battery (#2/0) 12-1/2" (Jumper)Service part / kit PartsGeek
416-0893Service part / kit PartsGeek
416-0921Service part / kit PartsGeek
501-0441Line, Fuel - Flex (Fuel In)Service part / kit PartsGeek
501-0502Line, Fuel - Flex (Fuel out)Service part / kit PartsGeek
503-0197Service part / kit PartsGeek
504-0011Valve, Shutoff (1/2”)Service part / kit PartsGeek
505-0026Coupling, Pipe (1/8")Service part / kit PartsGeek
505-0050Nut, Cap - Hex Head (#10-32 x 30mm)Service part / kit PartsGeek
505-0059Service part / kit PartsGeek
505-0098BandService part / kit PartsGeek
505-0185Service part / kit PartsGeek
505-1373Service part / kit PartsGeek
526-0008Service part / kit PartsGeek
526-0115Washer (5/16 “)Service part / kit PartsGeek
526-0196Washer, Spacer - Shield JC)INT, BALL LINKAGEService part / kit PartsGeek
526-0327Service part / kit PartsGeek
800-0012Screw, Cap - Hex Head (1/4-20 x 2-1/4”) Begin Spec C MANIFOLD KIT, INTAKEService part / kit PartsGeek
800-1003Service part / kit PartsGeek
800-2060Washer. Lock - EIT (5/16")Service part / kit PartsGeek
800-2110Hood, Inlet - Air MoldedService part / kit PartsGeek
800-2112Screw. Cap - Hex Head (M12 x 30nin)Service part / kit PartsGeek
812-0075Service part / kit PartsGeek
813-0103Service part / kit PartsGeek
815-0172Cover, Adapter OutletService part / kit PartsGeek
850-0025Service part / kit PartsGeek
850-0030Washer, Lock - Spring (#10)Service part / kit PartsGeek
850-0050Washer, Lock - Spring (3/8”)Service part / kit PartsGeek
850-2006Washer, Lock - Spring (M6)Service part / kit PartsGeek
850-2008Heater, Engine CoolantService part / kit PartsGeek
850-2012Washer, Lock - Spring (M12)Service part / kit PartsGeek
856-0013Service part / kit PartsGeek
860-2007Screw, Machine - Round Head (M10 x 32 x 3/4")Service part / kit PartsGeek
870-0053Service part / kit PartsGeek
870-0131Service part / kit PartsGeek
870-0212Nut, Locking (1/4-20)Service part / kit PartsGeek
871-0010ENut, Hex (10-32) ‘853-0006 Elackwasher 526-004$Service part / kit PartsGeek
871-0028Service part / kit PartsGeek
928-0502BService part / kit PartsGeek
928-0506Service part / kit PartsGeek
960-0135Service part / kit PartsGeek
960-0136Battery, 24V, 55Ah, AGMService part / kit PartsGeek
960-0242Service part / kit PartsGeek
960-0504AService part / kit PartsGeek
960-0505Service part / kit PartsGeek
960-12Service part / kit PartsGeek
K19-CP460 kWe1Service part / kit PartsGeek
K38-CP920 kWe1Service part / kit PartsGeek
K50-CP1240 kWe1Service part / kit PartsGeek

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.

Available documents

Reference — 0043090 (Cummins/Onan)Service manual — CONTENTS-Cummins-B-Series-Troubleshooting-Repair-3666087-588pages (Cummins/Onan)

Other sets with this engine

Cummins/Onan DGBCCummins/Onan DGCACummins/Onan DGCB