Low oil pressure on new 4.2 engine? what style pump

[Tripwire]

I have low pressure on a newly rebuilt 4.2 engine

at idle its about 5 PSI and at speed its only about 15.... if you run for a long time it drops even lower
the old engine had much higher

I swapped out the mechanical gauge with another one for testing purposes with same results

It dosnt seem to build up/drop when reving the engine like the old motor..

I am running Nappa gold filters and have changed them twice

Im going to try another new oil pump and pickup tube....I only want to do this once ( ok twice) should i go for a high volume or high pressure Any brand recomendations - im thinking the pump that came with the new motor was a cheap POS

help me obi Wan

[Ristow]

high volume.

you may have left a plug out in the oil system in the motor.

[Tripwire]

Yep ...i was thinking that also - i read on the internet there is one behind the timing gears that often gets overlooked... can anyone clue me in to its location? i dont wanna block off something thats supposed to be open

I just picked up the rebuilt and installed.....did not look for missing stuff

Thanks
Trip

[Tripwire]

Ok ordered a melling oil pump - high volume and a new pickup tube....also a gasket kit in case i need to remove the timing cover to look for missing galley plugs

Any tips on installing the pump?

I have always used kork gaskets and lots of goo to seal them - the felpro has a rubber gasket - do i need goo for this as well?

Thanks !

[Wayne]

Just install the gasket dry.

[TooRisky]

yup install it dry...any little leak will swell the cork for a better seal...

[jeepjerry]

A friend of mine had low oil pressure in his 230k mile 4.0. It got down around 5 psi hot at idle but the motor still runs pretty good so i suggested doing a high volume pump. He put the melling into it and now it gets down to 15psi at hot idle which is much better. Its around 35 psi cruising which is plenty unless you are beating on it a lot.