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Cummins QSK78

QSK78 Series

In Production

Cummins QSK78 77.627 L V18 diesel engine for generator and industrial constant-speed applications. EPA annual certification data lists up to 3,312 kW mechanical power at 1800 RPM. U.S. EPA Tier 2 / U.S. EPA Interim Tier 4 / U.S. EPA Final Tier 4. Electrical ratings are stored only where an official Cummins generator-set rating card identifies the exact engine model.

Cummins QSK78 77.627L V18 diesel generator engine specifications
Cummins QSK78 77.627L V18 diesel generator engine specifications
Electrical Output
3,312 kW
Cylinders
V18
Displacement
77.627 L
Rated Speed
1,500 RPM

Cummins QSK78 generator set context

The Cummins QSK78 is listed here as a diesel generator-drive engine for 50 Hz generator sets, with a headline 3,312 kW / standby rating. Use this page to compare the published engine output, electrical kWe/kVA ratings, emissions level, datasheet availability, and neighboring models before specifying an alternator, controller, enclosure, voltage, and compliance package.

Also searched as

qsk78Cummins QSK78QSK78 Series QSK78

Technical Specifications

BrandCummins
ModelQSK78
SeriesQSK78 Series
ConfigurationV18
Cylinders18
Displacement77.627 L
Fuel TypeDiesel
Ignition TypeCompression Ignition
Cooling MethodLiquid-Cooled
Emissions StandardU.S. EPA Tier 2 / U.S. EPA Interim Tier 4 / U.S. EPA Final Tier 4
CertificationsU.S. EPA Tier 2, U.S. EPA Interim Tier 4, U.S. EPA Final Tier 4
Country of OriginUnited States

Frequently asked questions

What fuel does the Cummins QSK78 use?

The Cummins QSK78 is a diesel generator-set engine.

What is the displacement and cylinder configuration of the QSK78?

The Cummins QSK78 is a V18 (18-cylinder) engine with a displacement of 77.627 L.

What emissions standard does the QSK78 meet?

The Cummins QSK78 is certified to U.S. EPA Tier 2 / U.S. EPA Interim Tier 4 / U.S. EPA Final Tier 4 emissions standards.

Is the Cummins QSK78 still in production?

Yes — the Cummins QSK78 is a current production model.

Is a datasheet available for the QSK78?

Yes — an official Cummins datasheet for the Cummins QSK78 can be downloaded from this page.

Reference

Last database update
2026-07-24
Manufacturer files
1 datasheet linked

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