If after verifying the oil PSI with a mechanical gauge and it indeed reads low, you can consider dropping the oil pan and shim the oil pressure relief spring to boost up the oil PSI.

 

I did verify it before and my pressure was going down to 5-7 PSI but I'm getting no rattling or rod knock when it gets really low.

Yes I have 40-50 PSI when it's cold but once it warms up (Running 5-10 minutes) it'll drop to 5 PSI at idle but goes up with RPM's.

I'm running the high volume pump & I'd read a few comments about shimming the relief spring. I almost did it before I put the pan back on.

 

If you think I didn't do anything wrong during assembly then what could have wiped out the bearings so quickly then? Of course I'm SWAG right now that it is a bearing issue since I can't figure out anything else that could be causing the low oil pressure. New gaskets and bearings for the engine from Summit will be here tomorrow. Clevite wasn't available so I got Sealed Power instead. Also my previous main bearings were half grooved bearings and the new Sealed Power are full grooved bearings. I'd read some where that the full grooved bearings were better for our engines than the half grooved.

 

Since you're getting no noises, I'm thinking that your main bearings aren't wiped. I'm thinking that your clearances may be a bit on the loose side. With my 150,000 mile 5.9, my oil psi starts off in the 40+ psi range at idle, but drops off to about 10 - 15 at idle once warmed up a bit, when watching the OE gauge on the dash.

 

I guess I'd just like to be able to figure out what caused the clearances to all of a sudden get looser than they were? I'm still toying with the idea of pulling the engine and installing the new bearings. It'd give me a chance to check everything out also. But I am also not enthusiastic about the idea either.

 

I had engines with worn bearings/cranks and even spun bearings and still had more pressure than 10 psi. I never ran thinner oil than 10/40. Just a few thoughts you may want to try before pulling the motor. Try removing the oil pressure sensor and installing a hose into a bucket. Pull the coil wire and crank the motor over and see if any debris comes out. Wonder if any debris is getting pushed up after it runs and is blocking pressure to the sender. Also may want to remove one of the valve covers and see if you have decent amount of oil coming up to the rockers. It can be messy so put a lot of rags around. Can also remove the distributor and run the pump with a electric drill if you don't want to run the motor. You could test this both cold and hot and see if there is any difference. If it is indeed leaking pressure finding the source is going to be the problem.

 

Those are some good ideas thanks. It just really bothers me that this is happening on a newly rebuilt engine and I'm not comfortable taking this off-road and being at steep angles with it acting up like this.

 

That seems more 'smart' than 'paranoid'.... Gotta be able to TRUST the vehicle you take out into the boonies. Getting to the bottom of the issue is definitely a good plan.

 

Wish it'd turned out to be something EASY but that isn't how this whole project has worked out to be. I'll do some testing and then if I don't figure out anything I'll pull the engine.

 

Engine warming up oil pressure is fine. This is 10-40wt oil BTW

https://youtu.be/svdc2r6t3Qo?si=ELFfEHU0Zc4Vr7df


Once it's warmed up to operating temperature, 205* it drops to 5-10 PSI


Shut it off and restart it oil pressure is reading nothing until I rev it.


I've misplaced my socket for removing the sensor. I think I left it at my sister house when I was working on my nieces rig. so I'll grab another one tomorrow and test things again and try some of the ideas suggested.

But the engine isn't rattling when the pressure is reading low either.