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Generac 3.9GN Generator Set

The Generac 3.9GN is a 40 kW Natural Gas or L.P. Vapor standby generator set powered by a Generac 3.9 GN engine. It is available at 120/240 V, single-phase and 60 Hz. It holds about 4.55 L (1.2 gal) of oil and 5.6 L (1.5 gal) of coolant, with a maximum ambient rating of 120 °C.

40 kW
Standby
3.9 L
Displacement
4.55 L
Oil capacity
1
Document types

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Specifications

FuelNatural Gas or L.P. Vapor
Frequency60.0 Hz
Standby power40 kW
Oil capacity4.55 L
Voltage options120/240 V
Phase1
Power factor1.0
Max ambient120 °C

Engine

Generac 3.9 GN
Oil capacity4.55 L
Coolant capacity5.6 L
Displacement3.9 L
AspirationNaturally Aspirated
Rated speed1800 rpm

Maintenance & consumables

for the Generac 3.9 GN
ItemSpecCapacityPart #Interval
Oil filterFull flow, cartridge
OilGear

Common questions

How many kW is the Generac 3.9GN?

The Generac 3.9GN is rated 40 kW standby.

What engine is in the Generac 3.9GN?

The Generac 3.9GN is powered by the Generac 3.9 GN engine.

What fuel does the Generac 3.9GN use?

The Generac 3.9GN runs on Natural Gas or L.P. Vapor.

How much oil does the Generac 3.9GN take?

The Generac 3.9 GN engine in the Generac 3.9GN has an oil capacity of 4.55 liters.

Fuel consumption

RatingLoadL/hgal/h
Standby25%132.057.0
Standby50%264.0113.0
Standby75%396.0170.0
Standby100%504.0216.0

Available documents

Spec sheet — 01693200EW (Generac)
Other sets with this engine