Does anyone know the acceptable oil psi for a 4.0? I have done a pressure test but i can't find any info on the proper psi. This is on a freshly built engine, all new bearings and parts, what psi should i expect? Thanks for any info!

 

do you have the RAVE manual on your PC, should be in there. If not I could look it up for you. BTW you can d/l the RAVE manual for free, do a search on here for the link.

 

i have the rave manual but i can't find it anywhere, i have googled it too.............no info!!

 

hmm i couldn't find it in the RAVE manual either. What are you getting from the pressure tester? I'm thinking it should be between 20-40psi but that is just a guess.

 

found it in the manual!!

Lubrication
System type .................................................. ................... Wet sump, pressure fed
Oil pump type .................................................. ................. Eccentric rotor
Oil pressure .................................................. .................... 2.75 bar (40 lb/in2) at 2500 rev/min with engine at
running temperature
Oil filter-internal .................................................. .............. Wire screen, pump intake filter.
Oil filter-external .................................................. ............. Full flow, self-contained cartridge

Looks like 40psi at operating temp, I have less than half that.

 

Is there a way to rebuild the oil pump??

 

You are going at this *** backwards.
Go rent an oil pressure tester and first thing one morning, prior to starting the engine, hook it up. You have to run 4 tests, cold at idle, 2000RPM's when cold, idle at operating temp and 2000 RPM's at operating temp, then get back to us with thos 4 sets of numbers.

 

Mike,
I understand that 4 test are called for, I have a mechanical gauge installed. The rave manual states 40psi at operating temp, that seems pretty straight forward. I hold under 20psi cold or hot, 2500rpm or idle. Could you please explain how the calculation of the 4 numbers are used?

 

You can get new gear for the pump, to answer your question. Most times it doesn't do much, and they are a bear to swap out. Have to pull the front cover. Then, if your mains are close to being gone, it won't make a difference

 

His engine has already been rebuilt, the oil pump should have been replaced when the engine was rebuilt.
Pull your oil pan and check the oil pump pick up screen for blockage.