Cad 331 oil pressure problem..help!

First time I've rebuilt a Cadillac 331. I got very low oil pressure. I know the bearings are correct and the pump is rebuilt. Are there any hidden galley plugs or bypass problems I might have missed? Anything peculiar to the 331 that comes to mind? I'm probably overlooking something simple and will no doubt feel like a stump when I figure it out, but any input is welcome. Thanks

 

Is your oil filter canister set up properly? Inlet/outlet, pinched oil line? When rebuilding the motor did you have the oil pump apart and repack it with a bit of axle grease?

 

How low... what are the specs on the oil pump compaired to what you are getting?

 

there is a plug on the inside of the block in front of the distributor gear. If you look at the back of the block there is on on the right side but that one is outside. It was when they drilled out the oil holes on each side of the banks for the lifters but you cant get that side from the outside because the distributor. If that plug isnt in there you wont have oil pressure. If i remember correctly you it is behind the left side plug if your looking at the back of the block. Hope this makes sense. I built a 52 motor last year but my memory isn't all that great.

 

I don't know how Cad oil pumps are set up, but having a ~.003 inch gasket under the cover plate for the gears dropped my oil pressure in my Buick by about 10 lbs. at cruise...no gasket--back to specs. Might be something to check out...

 

Thanks for the input. The pump was rebuilt by a shop in Texas, I did not take it apart to mic it or pack and prime it. I will look for the galley plug and insure it is there. I'm thinking it is bypassing one of the galleys. Pressure is 4-5 psi.

 

I hope it wasnt a shop in ft. worth .

 

Take apart the pump and have a look under that cover. If there's a gasket, get rid of it and check clearances between the gears and the pump. If there's enough clearance, that might be your problem. Also, you'll be able to check your bypass...Do you know the clearances you built into the motor? Did you do the cam bearings?

 

Problem solved! Jesus was right about the the galley plug in front of the drive gear for the distributor. A rookie mistake on my part. Thanks to everyone for input.

 

Great! Everyone makes mistakes--at least this one was an easy fix!