After smacking my valves and pistons i had my whole motor rebuild, everything new. ZC block/z6 head.

after rebuild : First it took forever to build oil pressure, once it did we started it, let it idle and warm up, then reved it and it was knocking, called the machine shop they said bring it back. pulled the motor brought it back they re measured the crank, rods and bearing. said it was good, bearing didnt even looked like we turned the car on. He said the knocking was from loose valves, so did the valve adjustment and dropped it back in, still no oil pressure and knocking.

they want me to pull the motor agaaaain, i asked if i should change the oil pump they said no because now we have to see again if anything is messed up.

could a brand new oem oil pump be bad?

0 oil psi at idle, 3000k it will slowly go up to 40psi

 

That's a horror story!
They (machine shop) didn't want to hear the car running? Motor still in.
I would never had made the decision to pull it first and not tow it to them for a listen.

I am doubtful the crank and rods are well with such terrible ol pressure.
The clearances at the crank and rod bearings practicly dictate oil pressure. Any knocking is BAD. Tapping loose rockers are not KNOCKS.

I would tow it to them intact and have them make good on it.

 

What was purchased for the rebuild? All oem, ebay, etc....etc....? Did the machine shop check to mmakae sure everything was within spec?

 

the cost of towing it to them wouldnt be worth it :/ and whos knows whats gonna have to be replace.

bottom end is zc block, stock rods, stock crank, acl bearing, p29 pistons, new oem water pump, oil pump, gates timing belt

cylinder head is comp 59300 cam, supertech valves and comp valve springs.


The stupidest thing is before i pulled it the first time i reved it to redline with no oil pressure yet the bearing still look new.

Any possible way its the oil pump or is it doubtful