SSPerformance

iTrader: (76)

new 396 and my car is barley reading on the gauge like5psi at idle i put a new sending unit in the car when i did the swap. the o ring is in the oilp pump perfect. Could i have a bad oil pump? it did the same thing in my 346ls1 with a 224 cam and caused the motor to spin a bearing. im runing a thunder racing ported pump and a double roller timing chain. they gave me shims to shim out the pump and i made shure the oil hole was lines up on the shims but metal to metal dosent that make u loose oil presure

TA2SLOW346

iTrader: (3)

Make sure the front and rear plugs are in the main oil passage in the block. Its right next to the oil pump behind the front cover and behind the rear cover.

SSPerformance

iTrader: (76)

i put a brand new one in the rear but neve check to make shure there was one in the front

SSPerformance

iTrader: (76)

car was also making 30psi till it got warm

Fade2blk500

iTrader: (18)

I would have put a new oil pump in it to begin with..

SSPerformance

iTrader: (76)

just got it all apart the front gallery plug is there. im gona put my stock oil pump back into it tomorrow and see what it does..... i think the oil pump is bad

kossuth

iTrader: (12)

Who assembled the motor??? Having decent oil pressure and then it falling off once warm is a classic example of a motor that is too loose. I hope it's just the oil pump like you were saying or something else. I got burned once with a rotating assembly kit for one of our tractors on the farm. Got the motor together and it only made 20 psi cold and lost all oil pressure at idle once warm. Tore it back down and plastigaged it like I should have to start with and found that the "precision reground crank" was over .003 out because it never even crushed down the plastigage. Got a new crank and bearings and it holds 60 psi all the time. A galley plug missing would more than likely kill all the oil pressure. Try the pump and see. Also if that doesn't work try a mechanical gauge on it. Maybe the cluster is messed up. Good luck

SSPerformance

iTrader: (76)

i platic gauged it from that start the motor was within spec the rod and crank where all .0015

kossuth

iTrader: (12)

Hmm, ok If you get it all together and it still doesn't hold pressure it has to be the o ring or something along those lines. What about the cam bearings??? That could also cause a drastic loss of pressure like that if they are way out of spec.

crainholio

iTrader: (2)

Sounds like you built the engine yourself and did your QC with plasti-gage...not good.

At least 3 measurements at different locations, with real micrometers not plastic squish, on each main and rod are the least amount of checking you can get away with for a decent assembly.

If you don't make at least two return trips to the machine shop for more journal polishing to get the clearances just right, you're not doing it right.

Try the pump, you might get lucky this time.

goober35

iTrader: (1)

Just for ***** and giggles did you put that O ring on the pick up tube right. It is not supose to be cramed up against that mount. It is supose to be right in front of that lip.

777

iTrader: (21)

Two things for the previous two posts. He had his motor built by someone else. He also said that the oil pump o-ring was put in right.

To be honest with you I would not mess with it. It may void the warranty. Just send it back and get it fixed.

Sorry about that I'm not positive if he built the motor or not. I just got finished reading a post almost exactly like this with the same cubic inch engine.

SSPerformance

iTrader: (76)

replaced the oil pump and it makes 35psi and a hot idel