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Subject:Re: Viscous Coupling survey
From:Brent Christensen
Date:Thu, 22 Apr 1999 15:29:36 -0700

First of all, I would suggest that you have another person sitting in the
cab that can hit the brakes or kill the ignition in the event of a problem
(sudden idle surge, etc.).  In my case, at full idle, the fronts would
engage, co I had to have this person apply the hand brake in order to slow
the rear wheels a bit.

Secondly, I positioned the jack under the crossmember that runs under the
engine/transaxle just forward of the exhaust crossover tube.  In my Westy, I
had to position the jack a bit more to the driver's side to compensate for
the extra weight on that side in order to lift both wheels equally.  Its a
bit of a reach if you have a short jack, so you may need to use a chunk of
4x4 between the jack and the Syncro frame piece.

Brent Christensen
'89 Syncro Westy "Klaus"
'91 Taurus SHO (For Sale)
'95 Cherokee Sport

----- Original Message -----
From: Kevin Sullivan <ksull@mbari.org>
To: Brent Christensen <bpchristensen@MINDSPRING.COM>;
<vanagon@GERRY.VANAGON.COM>
Sent: Thursday, April 22, 1999 2:26 PM
Subject: Re: Viscous Coupling survey

> I'd be interested in performing this test but being mechanically
> dyslexic, I could see the front wheels grabbing, the rears coming
> down and the floorjack end-over-ing or the extended part  puncturing
> some underside part of the van.
>
> My question: where do you place the jack and how keep the van from
> rolling foward if the VC is working?
>
> Kevin
>
> -----Original Message-----
> From: Brent Christensen <bpchristensen@MINDSPRING.COM>
> To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
> Date: Wednesday, April 21, 1999 9:28 AM
> Subject: Viscous Coupling survey
>
>
> >I think it would be interesting to see how many of the Syncros out there
> >will idle freely at 1,000 rpms with the rear wheels spinning in the air
and
> >not engage the front wheels.  If you have a Syncro and a floor jack with
> >wheels it is a relatively simple test.  If you have time, please try it
and
> >report back to the list.
> >
> >My Syncro will engage the fronts at the  full 800-1,000 rpm idle speed,
but
> >if I slow the rear wheels down a bit using the hand brake, then the
fronts
> >will disengage.  I wonder if my VC is toasted...  ???.  (The fronts grab
> >while making sharp turns in parking lots, but don't seem to act up at
> "road"
> >speeds.
> >
> >Brent Christensen
> >'89 GL Syncro Westy
> >'91 Taurus SHO (For Sale)
> >'95 Cherokee Sport
> >
> >----- Original Message -----
> >From: Dr. Rainer Woitok <woitok@rrze.uni-erlangen.de>
> >To: Joel David Shortlidge <shortlid@expert.cc.purdue.edu>
> >Cc: Steve <Steve@Schwenk-Law.com>; <wt@iscnet.co.uk>;
<Syncro@onelist.com>
> >Sent: Tuesday, April 20, 1999 3:55 AM
> >Subject: [Syncro] Re: Viscous Coupling
> >
> >
> >> From: "Dr. Rainer Woitok" <woitok@rrze.uni-erlangen.de>
> >>
> >> Joel and all others,
> >>
> >> On Mon, 1999-04-19 15:55:41 -0500, Joel David Shortlidge wrote:
> >>
> >> > ...
> >> > How can you tell your VC is frozen???
> >>
> >> VW's original (German) repair manual doesn't say much  about how to
test
> >> the viscous coupling.  They only recommend placing the  rear wheels in
a
> >> break testing stand.  If you then switch to  the G-gear (creeping
gear),
> >> the front  wheels should move the van  out of the  test stand as soon
as
> >> the engine is revving slightly above idle.   If the front wheels fail
to
> >> do so the viscous coupling is to be replaced, VW  says.  VW adds
another
> >> tiny sentence  to this, saying that only  when the engine  is revving
at
> >> idle and with the G-gear  switched in, the viscous  coupling is able
to
> >> absorb all the torque to the front wheels and keep them from moving.
> >>
> >> To me  this   last and  rather   ill-formulated (in the  German
manual)
> >> sentence is the key to testing the viscous coupling.   For in most
cases
> >> we  are not dealing with viscous  couplings doing less than their
share,
> >> but rather with hard-going viscous couplings  which don't have a
problem
> >> at all in  moving the van  out  of the  test stand with  the engine
just
> >> idling.
> >>
> >> Thus the really important thing here is not the van successfully
leaving
> >> the test stand.  On the  contrary, the important thing  here is the
van
> >> not moving and staying put in the test stand with the G-gear switched
in
> >> and the engine just idling.  If your  Syncro doesn't pass this test
your
> >> viscous coupling is probably  worn out and  ready for a replacement.
Or
> >> put  the other way  round: as  long  as your van's  viscous  coupling
is
> >> working properly you will not notice your van has got one.
> >>
> >> As   soon as   you are encountering   problems   with your Syncro
when
> >> cornering, in particular after a long and  fast drive, or  as soon
as --
> >> despite  of power  steering --  steering becomes   a  bit difficult
when
> >> turning and the Syncro slows down considerably when going round a
corner
> >> ... as soon as one or  more of these  things are happening, your
viscous
> >> coupling is most  probably due  for  replacement.  When  the tires
start
> >> whining while cornering it might well be too late already ...
> >>
> >> Hope this helps.
> >>
> >> Sincerely
> >>  Rainer
> >>
> >> '89 Caravelle GL Syncro 16"
> >>
> >>  ----------------------------------------------------------------------
> >> | Rainer M Woitok                  | Phone: (+49-9131) 85-27811,-27031
|
> >> | Regionales Rechenzentrum         |
|
> >> | Friedrich-Alexander-Universitaet | Fax  : (+49-9131) 30 29 41
|
> >> | Martens-Strasse 1                | Telex: d 629 755 tf erl
|
> >> | D-91058 Erlangen                 |
|
> >> | Germany                          | Mail: Woitok@RRZE.Uni-Erlangen.DE
|
> >>  ----------------------------------------------------------------------
> >>
> >>
>
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