I suspect rear PSRU seal problems are caused by Tracy's input shaft not
   being concentric with the e-shaft. That means the needle pilot bearing
   in the aft end of the e-shaft has not been properly removed or the
   input shaft diameter does not fit the hole perfectly.
   One needs to check the run out with a dial indicator.
   --
   Paul Lamar ...No rotor no motor.
   ------------------

   In my case I think the issue is the type of seal used. I replaced the
   mounting plate recently for other reasons, and Tracy tells me that
   the press
   fit seal used in the new plate does not have the imbedded metal
   flange which
   the original had.  I can see that the seal has moved out of the
   plate 1/16 -
   3/32" until it is against a shoulder on the damper plate hub.  I was
   able to
   pry it back in and it moved with relative ease, but it didn't stay
   in.  With
   the exit oil temp from the drive reaching as high as 250F during
   high power
   (3-rotor); I suspect the input shaft gets somewhat hotter.  Without
   a metal
   flange the elastomer seal has likely lost its compression fit.

   The original seal went close to 30 hours with no leak, this one
   leaked after
   a few hours.  I have a new seal, with the imbedded metal flange, and
   will
   probably replace it this week.

   Al

   Thanks Al for the heads up. Try one of those high buck McMaster
   Teflon type.

   Paul Lamar ...No rotor no motor.


Hi Al,
Wow, I could have written that paragraph myself, word for word.  Three
weeks ago, I discovered I had a leaking psru seal that had slipped out
of place and was pressing against the flex plate adapter hub.  The
difference was that I built this adapter plate in order to relocate the
starter.  (So, it wasn't Tracy's fault.  The old adapter plate still has
the original seal installed.)  I tried to fix it by pressing the seal
back into place then drilling and tapping an 8-32 hole for a flat-head
screw to keep it from moving.  I put it all back together and guess
what... it still leaked.  But I think the cause was that the seal was
damaged by the input shaft splines when it slid out of place.  I figure
that it wore it down enough to allow the seal to leak under pressure.

So, I bought a new seal, removed the psru and prop (a second time),
replaced the seal, reassembled everything and all is well now.  It only
has an hour or two on the new seal, but it does not appear to be leaking.

The seal was a National part.  Going from memory, I think the p/n was
3500090, or something similar.  I would have to check on that to be
sure.  It was a nice tight fit.

Mark St.

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