i had a new motor in my z but had to pull it backout because it had no oil pressure after 20 miles. when i took the intake off, i noticed that some of the memaining oil left in the lilter valleys showed signs of water in it. it had the coffee with cream in it look. i also noticed the oil had a tint of dark green to it and metal dhavings in it. i didnt notice any leaks in the head gaskets and the block has no cracks in it. i also didnt see and white smoke from the tailpipes. my question is, I have an oil cooler, could this be leaking antifreeze into the oil filter somehow. where else could antifreeze get into the oil. my intake is not crakced either. this car is a 91z28 350tpi

 

maybe the intake gaskets didn't seal up. I've had nothing but trouble with felpro intake gaskets. So I buy all my gaskets at the dealer (about the same price) and I haven't had any problems since.

 

i only use gm gaskets. that is what was on it the first time. it they didnt seal then where would water come from.

 

I second that, I had the same problem, turns out I forgot(actually, my buddy forgot to tigten the back 2 bolts on the intake as I let him put on the Edelbrock Throttle bracket) and it pissed coolant into the oil.

 

does coolent flow through the intake or just the tb

 

Coolant comes up to the intake base (sometimes flows as well) at the back of the heads; and into the base to the thermostat at the front of the heads. You should have coated the intake gaskets with sealant around those four holes. Any one of them can definately leak coolant right into the lifter valley. A cracked head at that point would leak coolant into the valley as well (never seen or heard of that, but anything's possible).