Little to no oil pressure on new engine start up.

[NachoBlanco]

I just finished my rebuild and droped my 79 regal t. 3.8l in my sandrail. I started it up, but have less than 5 psi oil pressure. and suggestions on why this could be? I am getting a flow of oil out of the turbo oil line, but no oil out of the pushrod and rockerarms. I rebuilt the oil pump (new gears, spring and piston) Any help would be greatly appreciated.

 

[STP]

Did you perform the front cam bearing mod?

 

[NachoBlanco]

I don't kno what that is, so I would guess no.

 

[Blown&Injected]

I would like to know about that mod too, but that is not what would cause little to no oil pressure.

Something is wrong! Passage blocked: gasket in the front cover/oil pump, cam bearing installed in the wrong position; Bad clearance: oil pump, bearings. Maybe a plug missing or leaking.

 

[NachoBlanco]

I know that all con rod bearings and main bearings are within .030. I checked these with plasti-gauge. The engine rebuild shop installed the cam bearings, so I might have made a mistake in assuming they are correct. I guexx i could take off the timing chain cover and double check the passages.

I read on the oil pump litterature that a thrust plate may be needed if the housing was badly scored. There are som minor marks in the housing, but i doubght there is enough to loose all oil pressure. Thanks, and please keep the ideas coming.

 

[Blown&Injected]

It .030 has anything to do with the bearing clearances - that is the problem, even .003 is too much on the rods and mains. Book says .0004 to .0018 on the mains. 4/10,000ths sounds way to tight, but .030 or even .003 is too loose.

It sounds like .003 may be OK for a full tilt race engine that runs a big oil pump and get a rebuild or bearings every xx number of passes.

 

[NachoBlanco]

I think I am wrong on the previously posted numbers. I will have to double check them tonight. I know I was within the recomended limits.

 

[Mark E.]

Just a guess, But are you sure the galley plugs are installed behind the timing chain gears?

 

[NachoBlanco]

I can't believe it, I bet that's it. I have two small plugs left from the gasket kit. Live and learn. I guess this kind of stuff happens when you have three monkeys putting together one engine. I will take off the timing chain cover and chain tonight. I really appreciate everyones help. What a great forum you have here.

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