You are more than likely correct about the exhaust gas, but it is the
inner
head gasket that has failed.
Moroso ceramic sealer (spelling?) is a great band aid until your piggy
bank
runneth over. I have 1 vanagon on the road had the same symptoms with
over
8,000 miles and still going. Replace your coolant cap also.
I also just treated a friends with external head leak, bad one, pushed
out
over a cup per trip.. He went to Florida and back from Chicago and is
still
going around town, with no visible leaks.
Were hoping to make it until summer to redo the heads I'll keep the list
posted if interested.
The archives should have plenty on the subject.

Good luck

Rob

Geo Hahn wrote:

> On an 83� water-cooled Westy the coolant level repeatly rises and
> ultimnately overflows.  The system has been carefully bled per
> instrucitons in the archives, but the problem recurrs.
>
> I suspect that combustion gases are getting past the piston gasket and
> into the coolant.