Dsumner

Hey guys, this is my first time on here and I'm looking for some help with my 1989 3.0L, the storey goes I got the truck cheap, loaded it on the trailer, got it home and pulled the trans, and rebuilt it due to a bad bearing witch was no problem, got it running and found a bad oil leak so I pulled it down and did cam seals, water pump oil pan gasket and oil pump gasket, this is where the nightmare begins, long storey short I have no oil pressure, I've pulled it apart 5 times now, 2 new oil pumps and new pickup, I've tried pressure priming the motor like an LS motor, I've tried back feeding from the oil filter, ive tried petroleum jelly, before all this started the motor had good oil pressure and now nothing, I believe it' just not priming itself for some reason, love the truck ut ready to do a 2.4 diesel swap lol

RJR

Are you positive the oil pressure gauge and/or sending unit are working? The oil pressure went to zero on my '94 a week after I bought it (130,000) miles. It was just a faulty sending unit.
Have someone screw a known good gauge into the port on the block.

Dsumner

Yes RJR, I have a manual 0-50 gauge where the sending unit goes

Co_94_PU

iTrader: (-1)

Needs to come apart again, sorry. Check the pump to crank interface, don't recall if it's pinned or has a keyway off hand. While it's off, bore brush the oil passages to make sure they are clear of gasket sealer (pickup tube, sensor galley port, galley passage to filter), verify the mating surfaces are flush and true for the pump and pick so it's not sucking air.

My money is on a missing pin or goop in the passages.
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