[TR] Oil Pressure/modern rear main seals

Michael Lang mlang99 at comcast.net
Wed Sep 16 22:47:21 MDT 2009


For what it's worth, I have put a couple of thousand miles so far on my
modern rear main seals with no leaks.

I sort of cheated, and it will be interesting to see how well it works
long term. Here is what I ended up with: I bought a used crank that
already had the scroll ground down. It was ground to 2.567" in diameter.
I purchased a seal kit from BPNW with a spec of 2.500". I bolted the
seal assembly to the rear main without the crank installed and measured
the ID which was 2.500". Zero interference didn't seem proper, so based
on everything that I read on the web, I just put it together the way it
was. It will be interesting to see if the 0.067' interference causes it
to wear rapidly and start leaking. Oh well, so far so good.

By they way, my freshly rebuilt engine has 20psi hot at 500rpm and 70psi
at 2000rpm when running 20W50.

Mike

dlylis at gmail.com wrote:
> I think you are talking about a 3A and since you have said "seal" I assume you have replaced the scroll with a "modern seal" that leaks in an "oh so modern way". I ground off the scroll and replaced with the "modern seal" and have regretted doing so as it leaks as bad as before. . . But I paid money to get it to leak like this this time. Unlikely your oil pressure has anything to do with the leak. 


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