When I rebuilt my 142, I partially disassembled the transmission and overdrive and replaced all the easily accessible seals and gaskets. This included the front seal and the little rubber O rings on the front cover retaining screws. I haven't pulled the transmission to confirm the source; but, 5 years later I seem to have a small oil leak from the front seal.

The service manual did not provide any specific instructions with respect to the front seal replacement other than don't forget the O rings. If I am going to drop the transmission to do the seal, is there any specific trick to installing the new seal correctly or did I just have bad luck when I installed the seal in the front cover.

As an aside, the transmission only seems to leak after use. When I pulled it out of storage in the spring or if it is parked for an extended period, it does not seem to continue to leak. I may have slightly overfilled the transmission. Would this contribute to seal leakage at the front.

Has anybody tried ATP stop leak on an M41? I am really not looking forward to dropping the box.