i have a 4.2 on my 88. It seems like there is a ton of pressure in the valve cover. When i take the oil cap off there is lots of smoke or fumes coming out and alot of oil coming in the air cleaner.
I have also noticed it seems like if i put oil in it takes a while to go to the crankcase. I dont think there is blow by because the plugs look clean and the motor still have decent power when the air filter isnt oil soaked.
Could there be enough sludge in there that the oiling holes are clogged that under running conditions the oil if forced into the valve cover but it doesnt return and instead just goes out the pcv into the air cleaner?
just want to check all options before an engine switch.