There is a gasket that seals the valve to the body of the heater. The
gasket is not like an "O"ring - round in cross section, but is instead
square in cross section. It fits nicely into a square shaped groove. I
have on a couple of occasions re-sealed this and stopped leaks by
applying "Plumber's Goop" - a brand of silicone sealer. It's not a
guaranteed foolproof fix however.

On 10/31/2012 11:27 PM, MICHAEL H wrote:
> ... that works well enough to heat the entire Vanagon has developed a tiny [for now] leak. it seems that the valve housing is plastic to plastic. I don't see a gasket. should there be one? can I fab one, put it in AND expect it to work ? hope everyone enjoyed a safe and happy All Hallows Eve. thanks for any help. mike - `85 GL 1.9L , auto.,A/C and a copy of the original Maroney in the side glass        =(: D)
>