Engine/Transmission (1994 - 1998) no oil pressure

[JKure]

I just changed my oil cooler and the oil bypass valve new gaskets now i dont have any oil pressure? I had 20lbs before i started? Any ideas there isnt away for the oil pump to go that easley?

 

[Vaughn MacKenzie]

Hmm. . . sounds like it's not seating right and letting everything bleed off.

 

[ata]

The oil pump in the Cummin's are gear driven and gear pumps. About as Bullet Proof as you can get. Something didn't go together right or working right. First thought would be the By-Pass valve.

 

[Matthug]

Umm even 20 PSI at idle is too low! I'd check for badly worn bearings or something thats making you loose oil pressure. I have 40 at hot idle. You are using 15W40 oil and not 10W30 or something right?