rear main seal

[Keithc8]

The one peice seal has help a lot. We check this on the dyno when we run the engines and we have some guys that call with a leak and we did not have it on the dyno. I have some guys over fill the oil pan, have a problem with the oil line at the front and it run back along with a few other things. I always try to oil dye the engine in the car if I have a leak to see if I can find where it is leaking for sure. I have evn had the transmissions leak and run out the bell housing a fool you. Good luck, Keith

[ou812545]

I recently had my 418w rebuilt. It's a 1971 block with the 1 piece seal.
The problem we ran into is the block was aligned bored a few times in it's life and the 1 piece seal did not want to stay in place. Due to the machine work, the location of the seal is no longer a perfect circle. The seal would actually work it's way out overnight as the engines sat on the engine stand. We tried some permanent cement and it seemed to work, Until!
We installed the engine over the weekend and after the first 100 miles, the seal is now leaking. We suspect it's coming from the out diameter. Between the seal and the block and bearing cap. No the seal and crank. We used the rigged steal stamped Fel-Pro rear main seal.

My question to Keith and anyone else who has run into this is?
Is there a rear main seal you recommend other than the Fel-Pro that may work better when the block have been align-bored a few times?

I can't be the first person to run across this problem.. Any suggestions?

Thanks,
Dan

[Keithc8]

We machine the block for the one piece rear main seal after we do the line honing so it is on the exact line hone center and with the crank center. We have very few rear main seal leaks on the 351W blocks or the after market Dart blocks which also use the one piece rear main seal. Just make sure you check everything because all leaks seem to end up at the rear of the engine. Good luck, Keith