

| 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 | > >> ---------------------------------------------------------------------- > >> > >> > >> ------------------------------------------------------------------------ > >> You can now easily share photos and documents with your fellow list > >members > >> http://www.ONElist.com > >> Check out our homepage for details on how to use our new shared files > >feature! > > >
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