Date: Wed, 19 Apr 2000 13:51:03 -0400
Reply-To: Derek Drew <drew@INTERPORT.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Derek Drew <drew@INTERPORT.NET>
Subject: Re: [Syncro] Viscous Coupling Rebuild
Content-Type: text/plain; charset="us-ascii"; format=flowed
Well, it sounds like there are some contradictory information coming from
the European manufacturer and the USA rebuilder.
Weddle finds better results by leaving no air in the unit. As you can see
from reading below, the factory views this as the gravest of mistakes,
likely to destroy the rebuilt VCs. Normally, the factory gives us a cold
shoulder, but I have used this post from Chris to force them to blurt out
the email reproduced below.
Weddle complains that the factory is withholding the information on how to
rebuild the units. The factory seems indeed to be holding back in that it
does not disclose the proper air percentage nor does it offer to sell the
replacement plates, merely stating that they are required to be changed.
Both parties are trying to help us and are our friends, so there is no
right and no wrong here. Just a situation that holds a certain amount of
tension.
Because SDP manufactures the Pinzgaur and Haflinger other super off-road
type vehicles, this would explain why it is biased toward a solution that
is slightly better for off-road performance.
The % of air issue where one party says there should be no air and the
other party says there should be air is truly odd. I do know that the
previous spec that was suggested to me from Visco Drive of having 14% air
has been tested by someone on the Net and I received a communication that
this air % is much too large, and that the VC does not function with this
much air. So anyone who has been recording the intelligences I have
received on this subject can consider the 14% figure suspect.
So ultimately, we do not know the proper air percentage.
There is always the possibility that Weddle and others had to go to a
lighter viscocity fluid because they eliminated all the air and that this
forced them to use the lighter viscocity fluid in order to compensate.
Although this is pure conjecture it is impossible to read the emphatic
statements of the factory that there must be air in the unit without
thinking it is a possibility.
On the downside, it appears that Weddle is in the experimentation stage on
these things. On the upside, there is no better outfit to be doing the
experimenting.
Chris, can you forward this to Oregon? I don't have their email address,
and I thought they might be interested to see the post below from the factory.
>From: sft.styr.com
>To: drew@interport.net
>Subject: AW: Re: [Syncro] Viscous Coupling Rebuild
>Date: Wed, 19 Apr 2000 08:57:16 +0200
>X-Mailer: Internet Mail Service (5.5.2650.21)
>X-MIME-Autoconverted: from quoted-printable to 8bit by mx.interport.net id
>CAA05943
>
>Dear Mr. Drew,
>
>1) Technical:
> What is being done by the company is in grave
>contradiction to our experience.
> Leaving no air in the unit, will cause the unit to
>disintegrate when going into the hump condition.
> Using a thinner fluid will result in less torque transfer to
>the front axle, reducing off road performance. If you can live with it, it`s
>o.k.
> The cause for a degraded performance of a VC unit lies in a
>change of the physical shape of the plates (microscopic wear of the burrs
>intentionally created when piercing the slots). Thus rebuilding the unit
>without changing the plates at the same time is an exercise in futility.
>
>Best regards
>
>W. G.
>
> ----------
> Von: Derek Drew [SMTP:drew@interport.net]
> Gesendet: Tuesday, April 18, 2000 7:15 PM
> Betreff: Fwd: Re: [Syncro] Viscous Coupling Rebuild
>
> Here is one of the companies in the USA that rebuild the Viscous
>Couplings.
>
> They leave 0% air in the Viscous Couplings and they use lighter
>weight
> fluid than you do. They say their units work better because they are
>not
> quite so stiff.
>
>
> >From: chris weddle
> >Subject: Re: [Syncro] Viscous Coupling Rebuild
> >
> >Bill,
> >
> >We purposely use a slightly thinner fluid than the factory uses.
>This does
> >make the VC slightly less aggressive. The reason we changed to
>thinner
> >fluid is that even with factory new viscous couplings, we get a lot
>of
> >complaints about the units being too stiff. The new thinner fluid
>has
> >virtually eliminated these complaints, and we have had no
>complaints about
> >lack of traction from those who take their vehicles off-road or in
>the
> >snow. We have never done any quantitative on-vehicle testing of the
>units
> >built with the thinner fluid, so I don't have any numbers to share
>with
> >you. I can only give you the seat-of-the-pants observation that
>(according
> >to our customers) the thinner fluid provides considerably improved
> >on-highway manners with very little loss in off-highway traction.
> >
> >In defense of our rebuilding technique (we do not leave air space
>in the
> >VC), we have had at least as many, if not more complaints about
>brand new
> >factory VCs as we have had about our rebuilt units. In fact, the
> >percentage of warranty returns has actually been higher on the new
>factory
> >units than on our rebuilt units. Of course we have only sold about
>30 new
> >VCs, so this may be a statistical anomaly.
> >
> >It is also worth noting that since we switched to thinner fluid,
>the
> >number of warranty claims has dropped dramatically. We have only
>been
> >using this new fluid for about a year now, but so far, I think it
>was the
> >right choice.
> >
> >It would be really great if someone could get VW to give us some
> >guidelines for rebuilding these units. That would eliminate the
>guess
> >work. The reason we don't leave any air space in the VC is not
>because we
> >know it is right, but because experience shows that it works. We
>have
> >tried leaving about 10-15% air space inside when adding fluid, but
>the
> >units didn't seem to work any better. Most of the properly
>functioning
> >factory built units that we have taken apart show no signs that a
> >percentage of air was left inside when they were originally
>assembled.
> >Maybe we are doing it all wrong, but we have to stick with what
>works.
> >
> >Regards,
> >
> >Chris Weddle
_______________________________________________
Derek Drew New York, NY
CEO & Co-Founder
www.ConsumerSearch.com
80 South Street, 2nd Floor
New York, NY 10038
derekdrew@consumersearch.com
drew@interport.net
212-580-6486
Alternate numbers for the industrious phone caller that wants to try every
avenue: 917-848-6425 (cell); 202-966-7907 (Work), 212-580-4459 (Home),
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