Mysterious engine sludge after 403 rebuild

[pontiacgp]

Your breather and pcv valve will be full, if it is an issue. It could also be unseated piston rings. My Olds 350 in my 4x4 is using oil and fouls two plugs after time. It needs a rebuild, pretty sure it has stuck oil rings. It has similar sludge.

offtopic but I would try changing the valve seals on those two cylinders

 

[Rob]

Unseated piston rings would explain the oil consumption I'm having. The rings were replaced during the original build, but as you can see, I'm not sure how much faith I have in anything he did.

Is there anything I can use to get the rings to re-seat? Seafoam or one of those additives? I've also heard that ATF down the spark plug holes may help.

Not sure how much confidence I have in any of these liquid remedies ...