>     My '84 Vanagon camper has this problem where every 30,000
>miles or so the head gaskets begin to leak, causing gas buildup in
>the water  cooling system.  This first appears as a rising coolant
>level in the overflow tank next to the oil dipstick. Next the
>dashboard heater quits because it fills with gas.  Finally (about
>2K miles later) the leaking gas literally blows coolant out of most
>of the cooling system and the temperature sensor begins to signal
>imminent meltdown!

I had exactly the same failure mode, but only after 115k miles.

>     This has happened to me three times now.  I travel alot, and
>so have talked to mechanics across the country. They imply it is a
>common problem, that VW doesn't really admit it exists, that there
>has been a service bulletin on it, that the only thing you can do
>is remove the heads and install new seals ($2K!).  

Why $2k?  I had my one head seal job done by the local dealer who cut no 
corners and it was about $900 with tax.  My response is that if it is fixed 
correctly it will last more like 100k miles.  My office colleague with and 
'85 GL got 85k miles.

Charles Vaughan
'84 GL