Mark 'n Mo wrote from the U.K.:

> <snip>We seem to have different problems over here.  As far as I can tell, heads don't leak but cylinder head bolts pop without warning due to corrosion.<snip>

I'm not sure but I believe that the only difference between the U.K, Vanagon and the North American Vanagon is a catalytic converter on the N.A. but not the U.K. If this is so, then the leaky head problem,  that we have but they don't, may be caused by that catalytic converter.

It is conceivable that the catalytic converter increases back pressure in the exhaust and consequently increases the temperature at the exhaust port. Excess heat could break down the coolant turning it acidic and cause head corrosion.

Do the real mechanics and/or chemists on the list think that this is possible?

Larry
'86 Syncro Westfalia in Ontario, Canada