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After completely rebuilding my Aerovee after a prop strike, I'm experiencing a major oil leak. It looks like it might be coming from the rear main seal even though the one that's in there now is new. Anyone had similar problems and can shed some light before I have to remove the engine again?

Pinpointing the source location of an oil leak can be more difficult due to the fact that the oil gets blown around under the cowling and can pool in certain locations that may look like the source of the leak when it actually is coming elsewhere. I would thoroughly clean the engine of oil, add a leak detector to your oil and make very short runs until you first spot the leaking oil location. Leak detector additives are readily available from just about most auto parts suppliers. If its the rear main seal then go ahead and remove the engine and replace it. There is nothing more annoying than an oil leak making a mess under the cowling.

Here's an older thread that may shed some light:

viewtopic.php?f=7&t=2163

Ryan offers an excellent post to review, but don't be surprised if you have to remove the engine and flywheel to simply replace the rear man seal. When I first ran my AeroVee, I had the same issue and it turned out that the spring inside the rear main seal had been kinked at some point. Long story short, this allowed an unequal seal on the flywheel flange causing an oil leak. I replaced that seal and all was fixed.

I know it's a pain to remove the engine block and flywheel but don't be shocked if it comes to that. The good news is, it really doesn't take all that long in the long run and you'll be all fixed once it's done.

Good luck!!

I did a really stupid thing a long time ago when I replaced the rear seal. I ran the engine only a few hours after replacing the seal. So the RTV on it had no time to cure. Leaked like a river! Other than that, a slight bit of damage or kinking when going in could do it. What about a leaking cam plug? That's back there, too. Oil sump plate?

I would guess the cam plug. The stamped steel ones are tough to get to seal correctly. They make a nice machined plug with an o ring now for under $10. If you pull tbe flywheel off also carefully inspect between the two webs on the right side of the back of the csse. It is an area the magnesium cases are known to crack. Its unlikely with a low time engine but worth a look since it had a prop strike.

Keith

MichaelFarley56 wrote:Ryan offers an excellent post to review, but don't be surprised if you have to remove the engine and flywheel to simply replace the rear man seal. When I first ran my AeroVee, I had the same issue and it turned out that the spring inside the rear main seal had been kinked at some point. Long story short, this allowed an unequal seal on the flywheel flange causing an oil leak. I replaced that seal and all was fixed.

I know it's a pain to remove the engine block and flywheel but don't be shocked if it comes to that. The good news is, it really doesn't take all that long in the long run and you'll be all fixed once it's done.

Good luck!!

How difficult was the removal of the gland nut. I am faced with the same effort
rory