[TR] TR3 New Rear Main Seal Leaking

Bob Nogueira Bob at texmog.com
Sat Jul 4 16:37:27 MDT 2009


The planets must not be aligned correctly! I too am having a problem with
excessive rear main leakage on a newly rebuilt engine. Having had bad luck
(major leaking with the Moss seal conversion some ten years ago, I opted for
the Greg Solow modification of the stock scroll sealing system. I'm not sure
that it is the seal that is leaking however.
After installing it and seeing the leak, I pulled the engine and took it to
a local well respected TR mechanic. He pulled the bottom end apart, checked
everything and reinstalled it right down to having a mandrel made to Gregs
specs.  IT is still leaking just as bad.
It is leaking 1/2 ounce of oil in every 100 miles ( yes I constructed a
catch system to capture the leaking oil). I beginning to think that it may
not be the seal that is leaking, that it is something else that is passing
the oil.

The question for the group is How do you deter main where the leak is coming
from?  I used the dye before taking the engine out again and what little
trace of color behind the flywheel were small and spread around with no
trail. The one area that had no color at all was between the crank and
aluminum scroll. Since I had someone else reinstall the scroll seal I'm hard
pressed to see us both screwing it up. As for the modification, the only
thing done is to reduce the clearance from .12 to .06 so I really don't see
how it would cause it to leak more.

My number one suspect is the freeze plug that blanks the end of the
camshaft. Anyone ever had a problem with that leaking?
Can that freeze plug be replaced with out removing the cam?
The freeze plug was new and installed by the machine shop. The Oil galley
plug was replaced with one supplied by TRS and installed with loctite thread
sealer.

I am also wondering if the oil might be leaking out the back of the oil pan
to block joint and being sucked or blown into the bell housing rather than
falling straight down. It would be nice if this was the problem since I
could do a fix without removing the engine. Any thoughts?  Any suggestions
as how to check the  pan for leaks ?

Bob Nogueira




> -----Original Message-----
> From: triumphs-bounces at autox.team.net
> [mailto:triumphs-bounces at autox.team.net] On Behalf Of David Lylis
> Sent: Saturday, July 04, 2009 7:01 AM
> To: bill_beecher at flash.net
> Cc: TR List
> Subject: Re: [TR] TR3 New Rear Main Seal Leaking
> >
> > Well I have now put 100 miles on the new engine, it runs
> great, but I
> > think I am actually leaking more oil than before the
> rebuild.  I know,
> > they are supposed to leak some, it a British right of
> passage, but I
> > went so far as to grind the crank to the fit the $150.
> > 'new-and-improved' seal from Moss that is supposed to


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