HomeEnginesCummins/Onan QSK78

Cummins/Onan QSK78 Engine Engine

The Cummins/Onan QSK78 is a 78 L 18-cylinder turbo charged and low temperature after-cooled engine rated at 1800 rpm, producing up to 2461 kW. It powers generator sets from Cummins/Onan, including the C2750 D5, C3000 D5, DQLE and DQLF. It holds 312 L (82.4 gal) of oil.

Also known as: Cummins QSK78

Part of the Cummins/Onan QSK78 engine family — 7 variants share parts & fitment.

78.0 L
Displacement
18
Cylinders
1800 rpm
Rated speed
2461 kW
Gross power

Engine specifications

Oil capacity312.0 L
Displacement78.0 L
Cylinders18
AspirationTurbo charged and low temperature after-cooled
Rated speed1800 rpm
Gross power2461 kW

Parts cataloged across the Cummins/Onan QSK78 family

7
Part #DescriptionCategory
0140-3963Filter, Air - Standard Dutyair_filter
A034R952Filter, Air - Heavy Dutyair_filter
A034R957Element, Primary - Heavy Dutyair_filter
A034R963Secondary, Primary - Heavy Dutyair_filter
908-0600Cummins QSK78 Series Engine Operation and Maintenance Manualother_service
A041X654Element, Replacement - Crankcase Breatherother_service
APCH-1007-12Bulletin 5600277other_service

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 Cummins/Onan QSK78?

The Cummins/Onan QSK78 engine has an oil capacity of 312.0 liters.

What is the displacement of the Cummins/Onan QSK78?

The Cummins/Onan QSK78 has a displacement of 78.0 liters with 18 cylinders.

Which generators use the Cummins/Onan QSK78 engine?

The Cummins/Onan QSK78 powers 5 generator set(s), including Cummins/Onan C2750 D5, Cummins/Onan C3000 D5, Cummins/Onan DQLE, Cummins/Onan DQLF, Cummins/Onan QSK78 series.