shrmpboatcptn

I'm working on a '96 dodge w/ a 12 valve cummins for a friend. It has a loud knocking noise that changes when you throttle the motor up. I think he has been hotrodding it because of all the oil i found that was blown out of the dipstick tube. I dont think the knock is from the injection pump because it is too loud. Does anyone have any ides as to what is causing this noise? any help is geatly appreciated.

TIMMY22

a bad lift pump will cause a tick,tick,tick.....

shrmpboatcptn

Its coming from the engine itself though which is why i dont think its an injector pump.

TIMMY22

lift pump and injection pump are two different anti-mules.

lift pump is down on the side of the block drivers side ahead and above the starter. the springs wear out on the plunger in the lift pump. the plunger then floats away from the cam lobe. gives you the tick,tick,tick....


injection pump is up high drivers side.

fschiola

You may have already checked but, how is the coolant level/ condition? How does the oil look, any gray matter on the dipstick?

shrmpboatcptn

Found the culprit.........bad injector on the second cylinder......replaced it and it runs great