g63b Issue

Got bored and took the head off the truck and got a valve job and new guides and seals. I blocked off all the emissions stuff on the intake manifold. Got everything back together and got it running. It ran good but once I got out the truck to check for leaks I saw a puddle of oil coming from the bottom end. The motor has high miles. I know it needs rings but I had no idea it needed it this bad. All I can gather is that the newly rebuilt head had so much compression on the worn out bottom end just pushed the oil back past the rings and out the oil pan. Let me know what you guys think?

your PCV valve is plugged up, causing the crankcase to pressurize. Start the truck and remove the oil filler cap - if you get smoke or pressure out of the opening, then you have pressure building in the crankcase. Bad rings will cause this if they are really bad, but if the PCV is plugged, it will still happen on a healthy engine.