Help with low oil pressure

[moparmike68]

It is weird to have to tell a seasoned shop "how to build", but they often have younger inexperienced guys doing much of the work now. In my case, I trusted the local builder to assemble my stroker. They did just that, assemble. My bearing clearance must be quite large due to the low oil pressure. The old saying of "trust and verify" applies here. I trusted but did not verify. They built engines for us in the past that were excellent.

Well this was an older guy that had an older shop with machines visible so I thought I was good. I thought”oh this guy is older and wiser and is probably good at rebuilding g engines over decades.Not too sure now🫩. You just never know

 

[Ricks72Chlgr440]

Well this was an older guy that had an older shop with machines visible so I thought I was good. I thought”oh this guy is older and wiser and is probably good at rebuilding g engines over decades.Not too sure now🫩. You just never know

Exactly. The shop I use is always really busy so thinking they just quickly built it and out the door. It takes a little longer to use plastigauge for bearing clearance but I doubt it was done. I know Mopar Joe said one time he sent back bearings in a stroker kit because they did not provide the correct clearance. It can happen, but machine shops should check for that.

 

[moparmike68]

Exactly. The shop I use is always really busy so thinking they just quickly built it and out the door. It takes a little longer to use plastigauge for bearing clearance but I doubt it was done. I know Mopar Joe said one time he sent back bearings in a stroker kit because they did not provide the correct clearance. It can happen, but machine shops should check for that.

No kidding

 

[rickseeman]

You said in your first post that you tried a high volume pump and it made no difference. I'm finding that hard to believe. I'm a B/RB oil pump guy. A HV pump is 1/4" thicker than a stock pump. Is that what you put on there? Last week I finished up a 383 rebuild. When I put it on the test stand it had low hot oil pressure idling. So I put a HV pump on and now it has 30-40. The engines in our classic Mopar muscle cars are over 50 years old. There are problems associated with this. One recurring theme you will hear about on the forums every month is “low hot oil pressure idling”. Yes it’s true, you have low hot oil pressure idling. Don’t panic. Your engine is not going to “blow up”. It will still make plenty of oil pressure when you are driving because the oil pump is turning more rpm’s. But when you are idling the engine might be turning as low as 700 rpm’s. That means your oil pump is turning 350 rpm’s. Engines wear. Even though your engine has been rebuilt, there are 16 lifter bores that are worn and there's a lot of oil passing each lifter. Factory rod and main bearing clearances were very tight. A rebuild today likely has more clearance. Your problem is very common. A M-63HV usually fixes the problem. If not you can go to thicker oil. (By the way, the stock spring is red or pink, usually will bypass around 55 psi. The black spring, sometimes called the hemi spring, bypasses around 75 psi. Use whichever spring you like.)