How to Prime a Cummins Fuel Pump

by Sameca Pandova

When the fuel filter on a Dodge Cummins engine has been replaced, or the engine has run out of fuel, the Cummins VP44 fuel pump must be primed prior to operation. Priming the fuel pump assures that fuel pressure is normalized in the fuel system, and reduces the wear and tear on the starter. While earlier model Cummins Engines utilized a manual primer lever, Cummins engines from Dodge truck model years 1998 forward utilize electronic priming.

Park the truck on level ground and let the engine cool. Make sure there is adequate fuel in the tank.

Locate the lift pump. It will be a large assembly on the driver middle side of the engine with fuel supply and return lines running to it, below the fuel filter.

Actuate the push button on the lift pump to purge air from the system. The push button exists only on earlier Cummins models (pre 1998 model year). On these earlier models, disconnect the fuel lines and actuate the pump until air is purged from the lift pump. After the air is purged, reconnect the fuel lines.

Bump the starter and leave the key in the on position to allow the electric lift pump cycle on 1998 and later 24v Cummins engines. The lift pump will cycle for about 30 seconds, refill the fuel canister, and prime the system. Repeat this process three or four times to assure adequate purging of the system. It is not advisable to crank the engine for extended periods as this puts significant stress on the motor.

About the Author

Based near Chicago, Sameca Pandova has been writing since 1995 and now contributes to various websites. He is an attorney with experience in health care, family and criminal prosecution issues. Pandova holds a Master of Laws in health law from Loyola University Chicago, a Juris Doctor from Case Western Reserve University and a Bachelor of Arts in history and political science from Case Western.

Photo Credits

  • photo_camera diesel image by Andrey Kiselev from Fotolia.com