Date: Mon, 26 Jun 2000 19:03:13 -0400
Reply-To: Dave Katsuki <dkatsuki@world.std.com>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dave Katsuki <dkatsuki@world.std.com>
Subject: Front eng clunk - miraculous cure!
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Finally found the source of a really annoying clunk in the front end of our
Westy!!
Details:
I've had a clunk (solid, metallic) when going over bumps of varying
severity for about 8 months which
sounded just like a loose ball joint and was driving me
crazy. Replaced all the standard parts of the suspension - shocks,
upper control arm bushings, upper ball joints, sway bar
bushings. Checked for loose everything - tie rod ends,
lower ball joints, inner tie rod ends, steering rack mounts, wheel
bearings, etc. Even went so far as to take the left hub
carrier out and try to press the lower ball joint out (didn't even budge
with my 12 ton press, and much
persuading, so I put it back together to wait for when I had the time to
take it to a machine shop.)
I also replaced the shocks again after 2 months on the old ones, since I
had a new pair and
was feeling pretty frustrated.
BUT, as I was contemplating the symptoms for the thousandth time, it
occurred to me that each time when I had
replaced the shocks (KYBs each time), the problem got somewhat better and
then got worse again. The shocks
also started feeling loose after a little while, like they weren't damping
the higher frequency road bumps as well.
I checked the upper donut bushings on the (new) KYBs, and they all were as
tight as they go and looked fine,
(since I had replaced them with the shocks), but just to eliminate a
possibility, I replaced the stock upper bushings
with much stiffer ones that I had left over from re-bushing the sway bar
link where it attaches to the lower control arm.
I also sawed another bushing of the same type in half and stacked it (total
1 1/2 donuts per shock) to make the upper
shock connection extra stiff. This not only fixed the clunk completely,
but the front end now feels tight like a new car!
My analysis - the stock rubber donuts that KYB ships with their shocks just
aren't stiff enough to anchor the shocks,
and they get even softer after a little while. On older vans (which all
of our are), it may also be that the rubber of the
bump-stop/shock cover piece that fits over the shock inside the spring has
compressed some, allowing the upper
donut to have insufficient preload. I've never replaced those pieces on
any of my vans.
Even if you don't have a clunk, I bet your front end will tighten up
considerably with a stiffer bushing.
I don't know what sway bar link bushings cost (Ron?), but they are probably
pretty cheap, and will certainly last for
a number of sets of shocks.
Dave
90 Westfalia
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