HomeEnginesCummins/Onan G12

Cummins/Onan G12 Engine

The Cummins/Onan G12 is an engine rated at 1500 rpm, producing up to 153 kW. It powers generator sets from Cummins/Onan, including the G 12.

Also known as: Cummins G12

1500 rpm
Rated speed
153 kW
Gross power

Engine specifications

Rated speed1500 rpm
Gross power153 kW

Service specifications

34
TypeItemValueUnitCondition
OtherCompression ratio10.5:1
OtherCompression ratio10.5:1(1); 8.5:1(2)
OtherCompression ratio10:1(1); 8.5:1(2)
OtherCompression ratio11:1(1); 8.5:1(2)
OtherCompression ratio12:1; 10:1; 8.5:1
OtherCompression ratio8.5:1
OtherEngine standby/prime power (W/Fan / W/O Fan)--kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10.5:1: 120/128/108/117; 8.5:1: 111/119/101/109kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10.5:1: 72/77/65/70; 8.5:1: 66/71/60/64kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)105/113/95/103 (both CRs)kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10:1: 154/162/139/147; 8.5:1: 150/157/135/143kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10:1: 178/186/159/166; 8.5:1: 168/175/151/159kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10:1: 222/230/169/177; 8.5:1: 205/213/158/166kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10:1: 278/288/252/262; 8.5:1: 265/275/240/250kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)10:1: 434/456/389/410; 8.5:1: 415/437/372/393kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)11:1: 223/235/187/200; 8.5:1: 210/223/178/191kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)11:1: 241/254/212/224; 8.5:1: 218/230/204/216kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)12:1: 102/105/93/95; 10:1: 97/100/87/90; 8.5:1: 91/94/81/84kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)12:1: 125/128/113/116; 10:1: 117/120/106/109; 8.5:1: 110/112/99/102kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)38/41/34/37kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)60/64/54/58kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/527/CLD/479kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/570/CLD/518kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/618/CLD/561kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/680/CLD/618kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/720/CLD/654kW60 Hz, 1800 RPM, 0.8 PF
OtherEngine standby/prime power (W/Fan / W/O Fan)CLD/788/CLD/716kW60 Hz, 1800 RPM, 0.8 PF
PressureSAE J1349 test condition: barometric pressure29.61in. Hg100 kPa; 300 ft (91 m) altitude
PressureSAE J1349 test condition: water pressure0.30in. Hg1 kPa
TemperatureRating note (1): water temperature to aftercooler, or use of air-to-air aftercooler with 100 F or lower air temperature to the radiator32C (90 F)applies to 10.5:1 / 10:1 / 11:1 note-(1) ratings
TemperatureRating note (2): water temperature to aftercooler, or use of air-to-air aftercooler with 130 F or lower air temperature to the radiator54C (130 F)applies to 8.5:1 note-(2) ratings
TemperatureRating note (3): water temperature to aftercooler, or use of air-to-air aftercooler with 110 F or lower air temperature to the radiator32C (90 F)applies to 10.5:1 note-(3) ratings
TemperatureRating note (4): water temperature to aftercooler, or use of air-to-air aftercooler with 130 F or lower air temperature to the radiator54C (130 F)applies to 8.5:1 note-(4) ratings
TemperatureSAE J1349 test condition: inlet air temperature77F25 C

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

FluidGradeStandardAmbientCapacityNotes
Fueldry processed natural gas905 BTU per standard cubic foot (33.72 kJ/l) lower heating value, used for the tabulated ratings; deration may be required due to altitude, temperature, type of fuel or use of a catalytic converter

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

Common questions

Which generators use the Cummins/Onan G12 engine?

The Cummins/Onan G12 powers 1 generator set(s), including Cummins/Onan G 12.