Quote Originally Posted by deVille33 View Post
Those grommets harden with age and exposure to engine heat. That's why yours seem like hard plastic. You could get them from GM several years ago, I'm not sure if they are still available.
If your going to replace the valve cover gaskets, take pics of your engine on either bank. That way you have something to go by when putting it back together.
When you pull the cover, look around for for oil seals, small o-rings. They dry out over time and if the guides get sloppy things don't travel in a straight line anymore. Usually the exhausts go first. Due to the heat produced, you get more wear. If throughout the history of the car the oil was changed regularly, the wear will be minimal, but with the milage you describe, over 200K, some wear is to be expected.
Check that your oil return passages aren't blocked up. Excess oil held up in the top of the engine can cause blue smoke at start-up, but it wouldn't stop after the engine warms up. It would reappear at low engine speeds. Pennsylvania oils have a tendency to build sludge because of their parafin content.
Hope this helps.
Could someone elaborate on the oil seal o-ring explanation? Are they something I need to order replacements for, or what? I don't know what they are. I'm still a bit green, but learning quickly. I bought gaskets & I'm getting ready to do the job ASAP. Also, my passenger's side valve cover has one broken bolt, and one missing bolt - on the very front & rear, respectively. Where would I find replacements, and how hard is it to remove a broken bolt from the head? Do I need to be worried about bits of old gasket falling in my engine, and what can I do it prevent this? Also, what should I use to seal the gaskets to the valve covers for installation? Gasket cement? RTV silicone? Anything else I need to know before diving in?

Thanks,
-Ben