Date: Fri, 14 Jul 2000 10:41:57 -0700
Reply-To: Daniel Schmitz <djs@gene.com>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Daniel Schmitz <djs@gene.com>
Organization: Genentech, Inc.
Subject: Re: Head gaskets
Content-Type: multipart/alternative;
The second shop is closer to the truth. The VW dealer obviously has
forgotten how the air-cooled Type 4 VW engine is designed. Assuming your
camper has an air-cooled, VW Type 4 engine in it, and not a diesel, It
should NOT leak oil from the "head gaskets," because there aren't any,
per se.
These are actually just metal sealing rings that are supposed to seal
the mating surface between the cylinder rim and the combustion chamber.
They can fail, but this results in a loss of compression, not an oil
leak. These sealing rings are not absolutely necessary, it turns out,
and they have been found to actually contribute to sealing failures
themselves. Many people (myself included), when rebuilding the aircooled
Type 4 engine, leave them out as the cylinder seals against the
combustion chamber just fine without them. Your engine, if original,
should still have them, but if it's been rebuilt in the past, it may or
may not.
You would notice a lack of power and some noise if you had blown one of
these sealing rings. If you are experiencing an oil leak, it is most
likely that the pushrod tube seals are leaking. On this engine, the
pushrod tube seals can be replaced without removing the heads, but it's
somewhat involved. If you do replace them, you should use the brown,
"Viton" type seals that are designed to last longer in high heat
environments. One reason why the pushrod tube seals tend to leak is that
they are damaged when installed. There is a procedure to install them
that prevents damage, and a competent VW shop that has a lot of Type 4
experience should be able to do the job properly.
If the engine is running good but simply leaks oil (as these air-cooled
engines often do), it's probably just your pushrod tube seals. I have an
'82 van and a Porsche 914, both using this same engine, so I know
whereof I speak.
Dan
"Paul Lindsay,Summit Resources/Triad Sportswear" wrote:
> anybody:I just purchased an '81 Westy with only 58K on it. the heads
> had previously been replaced. After taking it in to the local VW
> dealer I was advised the head gaskets and push rod tube seals need
> replaced.secondary followup by a shop specializing in foreign cars
> and I am sure much more exp than the guys at our dealer states that
> the kind of oil leak I am getting is not head gaskets but should just
> replace the push rod seals.any experience or thoughts out there?Best
> regards, Paul A. Lindsaypaull@triadsportswear.com
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