Thanks Rico!

I replaced the expansion tank cap today, hoping to avoid future
trouble until I can get this diagnosed. I am getting a lot of folks
suggesting head or head gasket leakage. Your explanation seems very
likely; a big thanks for the idea to take it to A RADIATOR SHOP!
Never thought anyone can test for combustion gassis in the cooling
system!

This is my first week on Vanagon.com and I really appreciate the help!

Sincerely,
Paul Cavanaugh
Columbus, OH

>This overpressurization of the cooling system is likely caused by a failure
>of the sealing ring at the top of the cylinder or a leak in the cylinder
>head.  This would allow combustion gasses to enter the cooling system and
>destroy the components you mention.  Take the van to a competent radiator
>shop and have them test the coolant for the presence of combustion gasses in
>the cooling system.  This happened on my 84 and it ruptured the rear heater
>core and one of the heater hoses.
>
>Rico Dagastino
>Munford, TN

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'84 Vanagon (217k)
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