Folks tend to replace the breather hose with heater hose, which is not
compatible with oil fumes.  It will work for a while, but will
eventually break down, get flabby, and collapse under heavy vacuum
pressure.

IIRC, the correct tubing is only available in large rolls.  That would
be a good club type purchase.  Any interest?

Karl Wolz

> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
Behalf Of
> millo fenzi
> Sent: Wednesday, January 04, 2006 9:19 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Failed Crankshaft seal yet again
>
> Hi David,
>
> Agree with the comment about excess crankcase pressure. Suggestion:
check to
> see if the crankcase breather hoses from the vent tower to the air
intake
> distributor are sucked flat at 2500 rpm.
>
> Story behind this suggestion. I acquired an abused 86 Westy Weekender.
It
> was leaking engine oil out the bottom of the clutch area, had a death
> rattle, and numerous other ills.  I replaced the engine with an AVP
core
> rebuild.  Transferred all the bits and pieces over to the new core.
> Replaced every hose that needed it. Had the end play adjusted by a
local
> shop and they put seal in. Put everything back together, started
driving and
> noticed I still had engine oil dripping from the bottom of the clutch
> housing.
>
> Hmmm.  Pulled the engine, seal looked fine.  Put a new seal in.  Still
> leaked.  Hmmmmm.  In desperation took it back to local garage (Fred's
Garage
> in Redwood City, CA)  They dropped the engine, replaced the tranny
seal,
> replaced the main engine seal. The mechanic noted that the seals were
fine
> so went looking for some other problem.  Found that the hose that
connects
> the  crankcase vent tower (little beer can shaped thing on the top
rear of
> the engine) to the air plenum (air intake distributor - black bulge
top
> middle of engine) was so old and soft that it was sucked closed by the
> vacuum from the airbox at anything over 2000 rpm.  This effectively
closed
> off the crankcase vent and drove up the pressure in the crankcase,
causing
> oil to blow past the main seal.  Stuck a new piece of hose on and all
was
> wonderful.  Time to fix problem, 5 minutes.  Cost of hose, $0.50. Time
to
> diagnose problem - 2 hours.
>
> Was tough to find as the hose looked fine at idle, only collapsed at
higher
> rpm, and since it's buried under a bunch of other stuff it is quite
hard to
> see the collapse.
>
> Three cheers to Fred's for finding it.  They felt responsible for the
> original seal, their mechanic pulled the tranny seal even though it
was
> clearly leaking engine oil, not tranny oil so they only charged me
$135 for
> the time it took to diagnose the problem.  My kinda garage :)
>
> Hope that this helps,
>
> Millo
>
> 86 Westy weekender
> 67 Porsche 912
> 00 BMW 528i
> 89 Chevy Pickup 1500