Date:         Wed, 21 Nov 2001 07:36:37 -0800
Reply-To:     Shawn Wright <swright@ZUIKO.SLS.BC.CA>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Shawn Wright <swright@ZUIKO.SLS.BC.CA>
Subject:      Re: Thumping when start van
In-Reply-To:  <2FAC6A580E76544C842BC944943D1B0C0293CC03@xch-sw-03.sw.nos.boeing.com>
Content-type: text/plain; charset=US-ASCII

On 21 Nov 2001 at 5:46, Greenamyer, William L wrote:

> Some of you may have experienced this.  The 84GL doesn't do it when I am
> trying to listen for the thump.  When I start it (maybe 40% of the time), I
> get a single thump and sometimes two thumps.  Everything starts fine and the
> van runs pretty good.  I am trying to attack some problems still remaining.
> There doesn't seem to be anything loose but I have been wrong on that before
> (and found a bolt or something missing on a bracket).  What it sounds like
> is maybe the motor mount is bouncing (for lack of better words to describe
> it).  There does not appear to be hard metal contact (like slamming two bars
> together) but it is more like two pieces of metal banging together through a
> piece of rubber.  Could the starter be causing this problem?

My '88 has been doing this for a while, and I've suspected engine mounts
also, since the front trans mount is shot, and the rears are probably
similar. When I had the trans out, I replaced the front mount by having a
shop press a Rabbit style mount inside the housing, since the OEM mount
was too much $$$. The Rabbit mount fits perfectly, but is narrower than
the original, and therefore only lasted a few years. The other thing I have
suspected is that somehow the clutch may be grabbing at startup, but it's
more likely a mount problem. One thing about replacing the front mount:
after doing this, I found the ability to drive the van at low speeds without
violent bucking was greatly improved, so this trans mount is an area to
check if you have the "bucking syndrome".
Since I'm preparing for an engine swap, I've not worried about it...

Shawn Wright
http://zuiko.sls.bc.ca/~swright
'85 Jetta TD
'88 Westy 2.1L