I took the manifold off of my 4age motor and I see oil in basically all of the 8 ports. Are the valve stems the cause of this?

Blow by from the valve cover...oil gets sucked thru the tube u see running from the valve cover to the intake manifold...get a catch can and plumb the calve cover to that and plug the port on the intake manifold...oil problem solved.

thanks a lot

The blow by from the valve cover breather and the soot from the egr make for a nasty combination, and really gum up the intake.

I just cleaned the throttle body on my current engine for the first time....there was 1/2" of goop on the backside of the throttle plate, and the inside of the manifold looks terrible as usual. (Hello vta valve cover breather and egr delete.) Now time to remove and the clean the manifold/tvis, and send the injectors off to rc for cleaning.....

If you're planning to just put a filter on the valve cover beather, you're going to have a mess on your hands. High lateral g left handers cause a lot of oil to come out of the breather. It's best to just use a catch can and plumb it back into the intake. The intake vacuum is useful for evacuating the vapors from the crankcase.

I have a line running to an empty tin can mounted above the valve covers with the manifold nipple capped. I did the same on my old car for almost 2 years with no issues. I shortened the oil change intervals a tad since there isn't vacuum pulling out the nasty crankcase vapor. Disclaimer: I wouldn't recommend running this setup at first on a rebuilt or new engine. Also, you won't pass smog like this and it's not dot compliant

Some blow by, albeit a small amount, will get through even with a good oil separator installed in-line on a closed system.