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Rear engine main seal review


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I am iin a quandary, may seem like a small thing, but I am in the process of putting my TR250 engine back together, to my knowledge and from everything I can tell I am working with a motor that hasn't been apart before.

Anyway this may sound nuts or not, I am in the process uf putting the rear main seal on, the old one looked pretty good, but you just always replace things like seals when you do a rebuild right.

So I put the new seal in and slid it on, while it certainly seems to seal it doesn't seem real tight, so I put the old seal on (without the seal plate) it seems by seat of the pants feel to be just a little tighter, I look at both, the old one has a little more meat to the rubber lip, is still soft and supple, shows no signs of wear whatsoever, and as I said seems to seal just a little tighter, so now I am thinking of re-using it. It even has little scroll effect ridges on the sealing surface, which the new one does not.

Can you tell I kind of like the old seal better, but on the other hand seems to make more sense on the face to use the new part.

So any collective wisdom, has seal technology and materials gotten better in the last 20 years, or is there a quality part on the car and a cheapo part from the new manufacturer?

I am off to get some new sealants and shop rags--hope to be enlightened when I come back so if yyou have an opinion let me know. Progress must go on, I have often said "they all leak" but I would rather the one I am working on now doesn't or any leaks are minimized.


I started with a flood of leaking seals.
My only leaker now is the main rear seal.

I just live with it and add oil when needed.



Great Pumpkin
Does it fit as snug as this one does?


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Paul, the old one is in fact orange, looks like the one above, the new one is black, didn't see a manufacturer on either.



Great Pumpkin
I think I'd get a new one before I put everything back together. This came from either TRF or BPNW.


Great Pumpkin
Make sure that you have that copper washer at 12 o'clock like Bob indicates above.


Luke Skywalker
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Glemon: You know, that's a tough one. Makes sense you'd change them;
but with some of the after-market parts being sold, I just don't know.

For instance: I just recently bought a rotor for my distributor. It
broke before I even started the car. I bought another better quality
unit and it worked fine. I seem to be able to discern the difference in
those parts clearly just by looking at them.

If that car has really high miles, you'd likely want to change; that's usually
most prudent....but with the parts now days...you never really know.
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