I had just finished replacing all the oil seals on my "leaker" only to discover that it still leaked! The leak was accumulating on the bottom bolt on the bellhousing, at the rate of a few drips per minute, and it was coming from the rear of the engine. It was definitely not the rear main seal, which I had just replaced, and besides the leak was clearly originating somewhere above that. I suspected the distributor, but have had that on and off the car 4 times now in the last day hours and could not convince myself that it was leaking.

I think I finally figured it out.

It was my new valve cover gasket, leaking at the back somewhere. I had neglected to scrape off part of the old gasket that had stuck itself to the cover, in the round area that goes over the distributor. It's hard to believe that it could make such a mess.

BTW crankcase pressure wasn't a problem, lots of vacuum into the manifold and the oil cap gets sucked to the cover at idle. I also ran a quart of engine flush through the oil separator to clean out any gunk.

Maybe someone can learn something from this.
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Matt L. Cary, NC three '89 740 sedans