While I'm replacing this gasket...

[brewtoo]

While I'm replacing the infamous upper cover U-Gasket to repair the oil leak on my '91 300E, what else should I replace while I'm at it? Since I'll have a number of parts off/loose I may as well replace the usual suspects.

What about the belt-tensioning parts?

And....does the front crankshaft seal leak on these cars or is it pretty much always the upper-cover gasket? My formerly benign leak suddenly got a good bit worse here lately.

Thanks

[psfred]

Replace the heater pipe 0-ring, and if the belt tensioner didn't return to the start mark when you loosened it, or the rubber shows signs of deterioration, I'd replace it -- the final clue is that you won't be able to correctly tension the belt. Idler roller comes with.

New valve cover gasket, and while you have access to the chain, check for stretch (usually minimal on this car).

New cap and rotor if the old ones are bad, and expect to replace the rotor carrier and shield, they usually break coming off.

Peter