F430 - rear main seal leak ?

This is really common. The clutch dust eats the rear main seal over time. As the car is a dry sump system they will not leak while running because the oil in the engine is minimum and it is being pumped to the sump in the gearbox. Once you turn the engine off the oil will eventually equalize between the engine and the sump. This puts the rear main under the level of the oil and they leak. Easy fix is to replace the rear main seal and inspect the clutch components while your in there.

 

If you put a rear main seal in, it is not an option to reseal the throw out bearing. It has to be done. Once you slide the gear box back, the throw out bearing then extends to the end of stroke. The clutch diaphram fingers have been holding it, so now it slides onto all of the clutch dust that is on the flange. It will leak if not addressed. I always allow my customer to have the option of replacing the clutch and ALL associated components. No need going in again for something you actually have apart now.

 

This is not an "easy" job.

Excellent point.

 

The oil is from the oil pan, not the trans, so park facing downhill.
The oil gravitates from the tank (clutch housing) into the oil pan through the oil pump.

I am a big believer in driving these cars. I tell clients all the time that just starting and moving it around won't do it. I also remind them that everything in the car should be turned on or off or adjusted and messed with. Every knob, button, switch, lever, handle, or whatever. Move it, or adjust it. Keep it all working The Italian tune up is a real thing. I have left HUGE black clouds of crap behind cars on test drives that just never get run hard. The rev limiter is there for a reason, you should know where it is and what it feels like. The oil temp need to get fully up as well to steam off the moisture in the engine. I have come back from test drives with the oil fully hot and just let the engine run with the cap off the tank and watch the steam roll out just to help get the moisture out. You won't get it all but try anyway.
Sorry for running off a bit, rant over.

 

Never heard of that one, but ... one can always reach for the stars. Not!

 

You could mess up the clutch if it gets oil on it. Right?

 

I am not sure there is a definitive answer as to why. Clutch dust doesn't really go inward behind the flywheel, I think not running is more likely or it just doesn't want to do its job. As for getting better, I don't think it will get better. Then again, it isn't really hurting anything except making a mess. Again, the oil comes from beck of the flywheel and doesn't get on the clutch so no harm there. Drive it until you can't stand it and then get it fixed.