[TR] oil seal update needed

Tony Drews tony at tonydrews.com
Tue Mar 30 23:24:58 MST 2010

Here's an excerpt from Uncle Jack's TR-3/4 engine building tips:
If you are going to install the aftermarket rear
seal, have the seal surface of the crank turned
to 2.525  whatever the current instructions may
say. These seals are leaky and they need all the
help they can get. The lip tension is too low.
Therefore, measure the length of the spring and
alter it to be exactly 8  long.

Put a very small amount of RTV along one edge of
the seal groove in the aluminum housing. Also put
a very light coat of liquid gasket sealer on the
surfaces against which the seal housing will
go.  (This is for the aftermarket rear seal. TFM)

5.     Install the seal on the crank. Arrange the
seal so the split will be on the upside / top
after the engine is right side up.  (This is for
the aftermarket rear seal. TFM)

The full "tips" page is here:

My custom billet crank came with the crank
diameter turned slightly too small (ARRGGHHH) so
I have been trimming a little bit off of one edge
of the seal with a very sharp knife and
shortening the spring a bit under 8".  I got that
to work last year - we'll see how that works out with this year's rebuild...

Tony Drews

At 12:23 PM 3/30/2010, Gary Nafziger wrote:
>I've been reading about rear crank main oil seal
>fixes on tr-3's for some time but the last posts
>were confusing to me (not difficult) lol.  I
>wasn't aware that the specs were wrong for the crank re-grind ect.......
>What are the correct fixes/grind for the
>crank?  Which technical articles are the best to follow?
>gary n.
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