No oil pressure on cold start

[DrHolliday]

Last weekend I replaced my head gaskets on a 454 BBC. Got it all buttoned up and everything worked great. I took it for a test drive and come back to find I am leaking oil out of the front of my oil pan. I did drop the pan when I had the heads off because I dropped a bolt in the motor. I did get the bolt out when I dropped the pan.

So I know my pan gasket did not seal. I'm changing it Saturday and using a felpro one piece gasket. But I've noticed a strange issue. I have 0 oil pressure on a cold start for about 30 seconds to 1 minute. Then oil pressure builds to about 65 psi. I know it's oil pressure and not the mechanical gauge because I have lifter noise until the pressure starts to build. I've also noticed on the highway oil pressure drops with RPM's. at 2500 on the tach pressure drops to about 35-40 psi and engine rpms fall it climbs back up to 65 psi.

I'm thinking the pick up tube is to blame. It might have come loose when I had the pan dropped? Just looking for ideas on what it might be. I do have a new oil pump to put in when I have the pan dropped too.

I'm running rotella 15w40 with 1 qt of lucas stabilizer.

 

[87scotty]

My guess is pickup to maybe it got bent when you had pan off? At the higher rpms more oil is in the block and the pickupmay not be able to grab it had this problem on a friends scout

 

[87scotty]

Or loose fell in pan lol

 

[bucket]

Could be loose/bent/cracked. I'm leaning towards bent, causing the pan to be too close to the pickup. Maybe a bunch of trash in the oil filter too.

 

[DrHolliday]

I got the truck apart and found more coolant sludge in the oil pan. Decided to pull the intake and re seal it again with better gaskets. Left the original oil pump in it because the pickup tube was welded to it. Right now I'm running cheap 10w30 that I'll drain tomorrow and refill to help rinse out some of the coolant. Oil looks clean, no oil pan leaks and the oil pressure is acting normal. 40 psi at warm idle 65-70 psi on highway.

I'm just keeping my fingers crossed that my coolant leak is finally fixed. if it's not I'll be pulling the motor to have the heads and block inspected and do a full rebuild while it's apart.