Date:         Fri, 3 Apr 1998 19:11:30 -0500
Reply-To:     Erik O <koesel@UAKRON.EDU>
Sender:       Vanagon Mailing List <Vanagon@vanagon.com>
From:         Erik O <koesel@UAKRON.EDU>
Subject:      Re: Head (gasket) fix
Comments: To: Bob Berkemer <berky@WIN.BRIGHT.NET>,
          "Vanagon@VANAGON.COM" <Vanagon@VANAGON.COM>
Content-Type: text/plain; charset=us-ascii

Bob Berkemer wrote:
>
> God I hated stats!      Lies, lies and damnable lies!
>
> Oh well..I regress....... It seems that there are two basic hypothesis
> for the failure of the head gaskets even though they seem to be linked.
> First is the bad water/antifreeze camp. Second is the bad grounding of
> anything/everything camp.

From the corrosion I've seen personally, I see no indication that the
coolant/water combination or grounding issues are the cause of this
problem, rather just signs of it. It is only under the headgasket
sealing surface where this problem is isolated. There are other places
you should find corrosion if the problem was one of the two above
causes. The whole head would corrode for that matter. That fact that
it's isolated under a surface that is supposed to be sealed makes me
think of other options.

Like I said in my previous post, you need to keep the coolant from being
able to force itself under the gasket. The way to do this is to make
sure the engine is at proper operating temp so the maximum clamping
force is applied to the heads and gaskets. Another way is to route the
coolant pressure around the engine (bypassing the internal head area)
while the engine is below a certain temp, thus lowering the pressure of
the coolant at the head gaskets. Until the engine reaches temp, the
thermostat restricts the flow and puts too much pressure at the gasket
sealing surface at a time when the clamping pressure is not optimum.
Hence the flexible rubber seals. That was VWs solution attempting to
compensate for using dissimilar metals for the engine. These metals have
different expansion/ thermal properties. Does anyone else agree with
this? bla bla bla I'm done for now.


>
> Bob
> 84 westy, "der bus"

--
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Erik O        Akron, Oh
82 GTI Westfalia
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