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304 V8 - Can't get ANY oil pressure

2477 Views 20 Replies 9 Participants Last post by  254Triple
1972 Jeep CJ5 with a 304 V8. All fresh rebuilt, new front cover, new oil pump basically everything new. I set the engine in frame today, put the break in oil in via the distributor. I am using the old distributor modified so I can attach to my drill to prime the engine. I also have a mechanical oil pressure gauge hooked up to the sending unit port. I started running the drill "clockwise" to build pressure and nothing, gauge never moves. I reversed the drill for a dozen or so rotations and then forward again and still no oil pressure.

I removed the oil filter(it was dry) and the oil pump cover plate. I packed it with moly engine assembly lube, put the cover plate back on. Re-Test - Still nothing. Pulled the oil pressure relief cap off, spring and took out the plunger. Did not see any blockage/problem and plunger moves easily into recess hole. Installed spring and cap, still nothing on Re-Test.
I remember when I set the new oil pan on, I verified the sump pickup was within specs, put blu-loctite on the threads before screwing into block. I have 6 qts of the break in oil in the pan right now. According to my dipstick it is about a qt overfull, but filter is still dry so it will drop and I will adjust as needed once I get oil pressure.

Anybody have some ideas/insight as to what I can try next? Everything I have tried still no oil pressure.
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Oh, ok then it makes sense that I did not get oil from this when I tried earlier. I did drain the oil out and used my camera up through the drain plug hole and verified as best I could that the sump was still intact and had not moved. It was still in the holder and it was west from the bottom up quite a ways.

So some good news is all of the new pump cover and parts are back in with the CORRECT gasket. I put fresh 10w30 Break In Oil in(5qts) and using the new WIX filter. It started to build oil pressure within a few seconds of hitting the drill button. Ran it at 65 PSI for about 10-15 minutes making sure rockers were getting a bath. All looked great. Left it alone for 20 minutes and went back to use the drill again and I immediately got 65 PSI of pressure. So it was either the previous filter or that port blocked off before and the gasket was kind of flapping over the channel. That could explain why it had oil pressure at first then zero?

Anyway thank you to everyone for your excellent suggestions, it is much appreciated.


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