Date: Sun, 10 Dec 2000 12:22:54 -0500
Reply-To: The Southards <southard@GIS.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: The Southards <southard@GIS.NET>
Subject: Re: 82 Diesel Vanagon - what caused cam bearing to fail?
Barbara:
If the mechanic has removed the cam shaft bearings, he should be able to
tell if the oil passages there are blocked. If the camshaft siezed, that
might explain the timing belt jumping a few teeth. Jumping a few teeth
will not usually create contact between the pistons and the valves, unless
the wrong head gasket was used. Your head may be toast, but maybe not.
Ask if the camshaft is scored, gouged or bent. The bearing caps can be
replaced.
However, the VW Diesel engine is DEFINITELY an interference engine. If the
VW Dealer mechanic says it is not, then you should immediately stop
speaking to this mechanic and speak to the Dealer Service Manager. You may
have a situation of incompetence and ignorance. At a dealership, this is
inexcusable.
Can you tell if the gasket has three notches? If so, the thickest gasket
was used and would not have contributed to any interference between valves
and piston. If the head gasket was too thin or installed incorrectly, that
should be readily apparent upon disassembly. The head will likely have to
be removed in any case. Make it a point to inspect the head and pistons
personally.
I think you may need to push the dealer for a better explanation ... and
some assistance. Your other VW mechanic friends could be helpful to you
here. It may be hard to pin the whole thing on the previous work, but the
dealer should be very sensitive to your future business and word of mouth
in the VW community.
Maynard OvO '79
'82 Westy Diesel "Reinhardt"
'93 EV GL "Klinger"
'00 Golf GLS TDI "WooHoo"
'84 Jetta GL TD
On Sat, 9 Dec 2000 14:49:48, Barbara Hardy <bhhardy@BELLSOUTH.NET> wrote:
> Our '82 Diesel Vanagon has just been diagnosed by the local VW dealer as
> having a failed cam bearing, and we're trying to decide what could have
> caused this, and what to do about it.
> We're afraid that the dealer may have caused this problem, but we can't
> prove it now. The details are..
>
> At 135K miles - head gasket replaced at the VW dealer.
> 1500 mile trip to Vermont.
> Change oil.
> Back to VW for the routine head retorque.
> 49 miles later - a very loud clacking sound started coming from the
engine,
> so hauled it back to dealer.
>
> Dealer diagnosis: 4 of the 5 cam bearings are shot, and the timing belt
has
> jumped a couple of teeth. The mechanic said that he has never seen
anything
> like it, but apparently the head lost oil pressure only to the cam
bearings
> (nothing else that needs oil was apparently harmed).
>
> He says the head is getting pressure fine - 80-90 lbs, the oil pump is
fine,
> and there is no blockage to the head ports. I asked if he could suggest a
> reason why no oil would get to the head and he said that it was possible
> that he put the head gasket on wrong initially, but had that been the
case,
> we wouldn't have gotten 100 miles beacuse the head ports would have been
> blocked.
>
> The mechanic suggests that when we changed the oil, the engine lost oil
> pressure somehow long enough for the cam bearings to go out. He says the
> next step is to replace the head, which will cost us $1700 (ouch!!).
>
> So, the mechanic does not know what caused the problem in the first
place. I
> asked about the valves, and he told me that this engine is
non-interference
> (!!). I talked to a couple of other VW mechanics and they assure me that
> this is not true. I don't know if the piston heads were damaged. So I am
not
> sure how much confidence in this mechanic.
>
> Possible explanations suggested to me by others are:
> - the cam bearing caps were tightened by mistake
> - the wrong thickness head gasket was put on, and when it was
retorqued,
> that closed the gap between the valves and the pistons, hence the noise,
the
> bearings, and the timing belt.
> - the timing belt jumped somehow and caused the damage (belt was not
> replaced when head gasket was).
>
> Does anyone have any other suggestions for what might be going on here?
We
> want to ask the dealership to cover some of the cost, but is this
> reasonable? My family is moving to Montant shortly, so there is a time
issue
> here, too. I plan to talk to the dealer on Monday morning.
>
> Many thanks!
>
> Barbara Hardy
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