2000 Silverado, 4.8L, recent rebuild

Danged thing has a pressure oil leak that I can't seem to find. I'm starting to think that I might have a ring problem, but I can't pull the engine down right now to check into it because the truck is the only thing I have to drive right now. Changing the PCV from the older rattle type to the newer fixed orifice with a smaller hole makes the problem worse. So I'm thinking... what effect would pulling the PCV valve out altogether and replacing it with an old style filter fix my problem until I can get another car and get this dealt with? If I drive it easy it doesn't leak, but if I get into it it'll build pressure and start blowing oil out.

I'm also stuck with oil leaks.

I know were they are comming from (oil dye). I can't get them to stop.

I'm considering using a vacuum pump...

It's got new seals everywere, rtv like crazy but no joy.

The parts guy says the new felpro oil pan gaskets shoud be installed with no rtv.

Speed didnt you have this problem before and end up fighting the dealer about it?

It builds crankcase pressure with higher load. That has to mean rings.

Mine leaks from idle.

Yes, that dealer put on an oil pan gasket then said I needed a crate engine. No troubleshooting at all.

Sucks, I'm also thinking rings, and both my dad and brother are saying the same.

I picked up a couple of crankcase filters today to see if this will help. Worse comes to worse, I'll pick up another engine and slap it in. If I can find something else to drive before it hits the fan I'll pull this one down and fix the problem.

Speeder wrote:

Yes, that dealer put on an oil pan gasket then said I needed a crate engine. No troubleshooting at all.

Sucks, I'm also thinking rings, and both my dad and brother are saying the same.

I picked up a couple of crankcase filters today to see if this will help. Worse comes to worse, I'll pick up another engine and slap it in. If I can find something else to drive before it hits the fan I'll pull this one down and fix the problem.

You can buy a leakdown tester and see if the rings are sealing properly or if the cylinder is ok or not.
I would bet if its the rings then either the wrong rings or end gap, cylinder was not honed properly/and or the honing grit was not properly cleaned from the cylinder bores' cross hatch scratches. this is where a lot of builds are cut short from shops

Did you by chance use chrome-moly rings?

Not sure on the rings. They were part of a kit. The guy that did the rebuild also does rebuild work for the local Chevy dealer.

Pulled the PCV out today, the updated version has a pinhole, no rattler inside. It's a hollow body. The hole is far smaller than the old one, and the leaking got worse, so it's definitely a pressurization issue. I've plugged the intake and throttle body part of the venting system and installed filter breathers on both valve covers.

Also did a cylinder pressure check, pressures vary from 150PSI to 180PSI for a 20 percent span difference. Not happy about that. If the filters stop the leaks, I'm going to stop messing with it. I've already started putting back money for a new engine, again. This time, just going to get a crate engine from the dealer. Wish I'd have gone that way to begin with, as I could have bought a crate engine, high performance heads, and the cam of my choice for less money and not had these problems.