View Full Version : Rear main seal

02-07-2018, 02:15 PM
Rebuilt 1962 F 134. Complete rebuild to factory specs. This engine has a two piece split rear main oil seal. Took great care in installing the seal as if it leaks this is a very time consuming repair. You have to take the entire power train apart and half the motor. With all my care after startup I had a couple drops of oil. Has anybody ever used rear main seal leak stop added to the oil? I know this is a poor way to fix but IF it works a good 20 plus hours labor will be saved. Any opinions abut this?

02-08-2018, 08:36 AM
[QUOTE Any opinions abut this?[/QUOTE]

Well, the first answer is "A couple of drops seem about right". For whatever reason, try as we will, seals just don't seal like they should. Maybe a few ten-thousandths of wear, or burnishing on the shaft - but they do drip. It takes a lot of drips to make a tablespoon. I just put cardboard under the drips.

Now, about stop-leak. Another 20- hours to replace the seal could give you another leaky seal. I'd try the gunk for a thousand miles or so. If it seals, great. Drain it then. If not, live with the drip or tear it down again.

Just an opinion - worth everything you've paid for it!

Post pictures!

02-08-2018, 12:37 PM
You reinforced my thinking. That is what I am going to do.