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Generac 4.2L V6 Gas

Legacy Liquid-Cooled Gas

Production Discontinued
This engine is no longer in production (discontinued 2012). Specifications and documentation remain archived for reference.

Generac 4.2L V6 Gas is a legacy naturally aspirated, liquid-cooled spark-ignited engine used in QT commercial standby generator sets including 35-48 kW nodes. EPA families rooted at AGNXB04.22L1 through AGNXB04.22NN record 49.3-55.4 kWm natural-gas and propane calibrations at the 1800 RPM certification test speed.

Generac 4.2L V6 Gas 4.2L V6 Naturally Aspirated natural gas generator engine specifications
Generac 4.2L V6 Gas 4.2L V6 Naturally Aspirated natural gas generator engine specifications
Electrical Output
55 kW
Cylinders
V6
Displacement
4.2 L
Rated Speed
1,500 RPM

Generac 4.2L V6 Gas generator set context

The Generac 4.2L V6 Gas is listed here as a natural gas generator-drive engine for 50 Hz generator sets, with a headline 55 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

42lv6gasGenerac 4.2L V6 GasLegacy Liquid-Cooled Gas 4.2L V6 Gas

Technical Specifications

BrandGenerac
Model4.2L V6 Gas
SeriesLegacy Liquid-Cooled Gas
ConfigurationV6 Naturally Aspirated
Cylinders6
Displacement4.2 L
Fuel TypeNatural Gas
Ignition TypeSpark Ignition
Cooling MethodLiquid-Cooled
Emissions StandardU.S. EPA Stationary
CertificationsU.S. EPA Stationary, U.S. EPA NSPS Subpart JJJJ
Country of OriginUnited States
Year Introduced2011
Year Discontinued2012

Frequently asked questions

What fuel does the Generac 4.2L V6 Gas use?

The Generac 4.2L V6 Gas is a Natural Gas generator-set engine.

What is the displacement and cylinder configuration of the 4.2L V6 Gas?

The Generac 4.2L V6 Gas is a V6 (6-cylinder) engine with a displacement of 4.2 L.

What emissions standard does the 4.2L V6 Gas meet?

The Generac 4.2L V6 Gas is certified to U.S. EPA Stationary emissions standards.

Is the 4.2L V6 Gas still in production?

No — the Generac 4.2L V6 Gas is discontinued (production ended around 2012). Its specifications and datasheets remain archived here for reference.

Reference

Last database update
2026-07-25
Manufacturer files
No datasheet linked yet

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