Date: Mon, 7 Jun 1999 20:45:29 -0700
Reply-To: Coby Smolens <cobys@WELL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Coby Smolens <cobys@WELL.COM>
Subject: Re: Tapping sound
Content-Type: text/plain; charset="iso-8859-1"
Sure sounds like a lifter to me, but I remember being fooled once by an '86
Canadian panel van that had us convinced it was a lifter, then we figured
"valve seat" but gave up on that idea - performance wasn't bad enough.
Turned out to be a rod bearing - so lets stick with lifters for a moment
more. I maintain that as a diagnostic measure STP of other heavy duty
viscosity booster is the thing that is going to pump that lifter up. Marvel
mystery oil is not that sort of a thing, although if the lifter is stuck in
the collapsed position it may help loosen it so it can pump up. _Which_
lifter can probably be determined in a couple steps: 1. listen with a
stethoscope to isolate to one side or the other. 2. Pull that valve cover
and either set the engine to top dead center (distributor rotor pointing to
that cylinder's plug wire) for each of the two suspect cylinders in turn.
Push in on the bottom of the rocker to feel for a squishy lifter - that'll
be your culprit. Alternatively you can remove the rocker assembly and push
on the push rods directly, making sure the inner end of the rod is in the
socket in the lifter.
If you find a bad lifter it is possible to remove it, disassemble it, clean
and fill it with oil and reinstall it. You've got to destroy the pushrod
tube to do this, but you can replace it with an upscale version of the old
1600 spring loaded tube available from your local dealer (I have a couple
used ones I could part with). I do NOT recommend replacing lifters with new
ones - they won't match the cam and could destroy it. I know from what I
speak on this one. I have personal experience. But do yourself a favor -
start with the STP. 20W-50 is not enough. Also, ten miles may not be enough.
I'm not foolin' - it can take a solid half hour, even more, of normal
driving.
Best wishes!
Coby
Valley Wagonworks
"Intimately acquainted with VW Vans since 1959"
Volkswagen Bus, Vanagon, Westfalia and Eurovan
Repair and Service Specialists
1535 Sir Francis Drake Blvd., San Anselmo, CA 94933
Voice:(415) 457-5628
Fax: (415) 457-0967
http://wagonworks.com
mailto:contact@wagonworks.com
Date: Mon, 7 Jun 1999 08:42:48 -0700
From: Mark Kazman <mark_kazman@RADIXTEK.COM>
Subject: Tapping sound
Thanks to all on mail list for their input on my stuck lifter problem.
This week-end I tried the advice of some members to drive it around for
10 miles of so to see if it loosens up. It didn't, so since I am not
completely sure if its the lifter or not I immediately dropped it off at
a local VW mechanic. It ran fine, no decrease in performance since
before the tapping sound, but I am still not sure if its the lifter or
not.
I talked to the mechanic about the oil change he did a week ago, and he
put in castrol GTX 20w40 and a new mahle/mann oil filter, so I guess
using a heavier weight oil did not help it. He said that if it is a
lifter that it really not a good idea to replace it, and that its a
labor intensive job. When he said that I could see dollar signs start
adding up.
If the cost is prohibitive and it is the lifter, I will try the next
list suggestion and try marvel mystery oil in the oil.
Can anyone tell me how you go about locating what lifter it is that's
the problem? Can I run the engine with the valve cover off? Any help
here is a benefit because I have never done this before, but I'm willing
to dive right in a save my engine. One list member laid out a basic
procedure on how to replace the lifter, but right now I would like to
know how to locate the faulty part without taking the whole engine
apart.
Does anyone on the list have a Bentley for a 81 vanagon they would like
to sell cheap?
Thanks to all who have offered suggestion's.
Mark Kazman
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