Date: Tue, 3 Jan 2006 08:10:14 -0800
Reply-To: gary hradek <hradek@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: gary hradek <hradek@YAHOO.COM>
Subject: Failed Crankshaft seal yet again
Content-Type: text/plain; charset=iso-8859-1
David,
I have had very little experience with this kind
of problem but I recall there is something call
crankshaft end play that is the amount of movement
that the crankshaft makes front to back and back to
front. This can be measured and corrected somehow???
Could this explain your problem? gary
Date: Mon, 2 Jan 2006 23:47:14 -0800
From: David Shepherdson
<shepherdsond@METRO.DST.OR.US>
Subject: Failed Crankshaft seal yet again
I just watched my 87 syncro Westfalia being winched
onto a flat bed tow
truck for the 3rd time in 5 months near Bend Oregon
this weekend, all
three times were the result of catastrophic failure of
the main
crankshaft oil seal. I am appealing to the list now to
solicit some
more
ideas about what could be wrong before I drive back to
Bend (from
Portland, Oregon) next weekend to try and fix it. The
first time this
happened was on a trip to NWT in Canada. That time it
was the part of
the seal that contacts the flywheel that ripped. The
next time the
break was on the face of the seal (hence the
hypothesis that the seal
had been rubbing on the flywheel (although it did not
appear to stick
out - the replacement was very well countersunk), of
course I don't yet
know where it has failed this time. I do however know
from looking
back
through receipts from the previous owner that this 40k
engine has now
had 6 main seal failures in its life. My current
hypothesis from
talking to mechanics at VW is that there is something
wrong with the
flywheel (it looked OK but I did not check the
diameter of the sealing
surface) so I have a freshly machined replacement from
AVP to replace
it
with. Needless to say the O ring was replaced each of
the last 2 times
and I also checked the end play last time which
appeared to be well
within limits (I will measure it again when I
dismantle it next
weekend).
Both the last two times the symptoms have started as
soon as the engine
was reinstalled. Oil leaked from arround the bell
housing from day one
after replacing the oil seal. Not a huge amount but
enough to spot the
rear door after freeway driving and leave a daily oil
mark on the
driveway. This suggests that the seal is under some
sort of stress
right from the start. Then after about 2000 miles the
seal fails
completely and all the oil drains out. I guess if the
flywheel diameter
was too small it could cause a leak but why the seal
then fails
completely I dont know. I am wondering if there is
anything that could
cause the oil pressure to be too high in this area
(faulty instalation
of bearings??). Or does anyone have any other ideas -
I am at a loss
now and if it starts to leak again after I replace it
this time I will
have to replace the engine. Unexpected catastrophic
failure of the oil
seal is just not something I can live with (it makes
me shudder to
think
of some of the places I have been where this could
have happened). All
ideas gratefully received!
David
__________________________________
Yahoo! for Good - Make a difference this year.
http://brand.yahoo.com/cybergivingweek2005/