Quite likely your surfaces are not flat.  If the pipe lays flat against the
head, the gasket will hold tight.  However, if they do not lie flat, one
side will be tight against the head and the other will be a bit loose, but
not enough that you could easily see it.  Under the higher pressures of high
RPMs, this gap will be exploited until it fails.  Likewise, you could simply
have a low spot on the surface of the pipe.  When you next replace the
gasket, file the pipe flat first, and scrape and smooth the head surface as
well.

Z

-----Original Message-----
From: Cookson, Noel [mailto:ncookson@CELOXNETWORKS.COM]
Sent: Monday, November 05, 2001 9:54 AM
To: vanagon@GERRY.VANAGON.COM
Subject: #1 cylinder header pipe gasket burning out

Hi,

I have a recurring problem with the gasket for the #1 cylinder header pipe.
This gasket fails after running the car at highway speeds for an hour or
more. Around town use has not caused a problem.

I have replaced this gasket twice now and even doubled it up to try to
accommodate any warping that might occur as things heat up. Has anyone else
seen this problem? Is there another/better gasket I should look for?

Noel

88 GL