I had the same problem!  I replaced the expansion tank last Wednesday and
have not had a problem since.  BTW the tank cost $55.00(dealer), I also
replaced the bottom hose while I was there.

Dan Moy
danmoy@cynet.net

On Wed, 26 Nov 1997, Christopher M. Smith wrote:

> On Wed, 26 Nov 1997 Erlaz@AOL.COM wrote:
>
> > I have developed another coolant leak but this time it appears to be coming
> > from one spot under the expansion tank cap. I thought that the seal under the
> > cap was the problem so I replaced the cap. The leak still appears. Could I
> > have a hairline crack in the expansion tank . Has anyone had this problem.
> > Let me know please. The vanagon is a 91 GL with 91,000 miles on it.
>
> It's likely a crack in the expansion tank. Leaking coolant appears to be a
> common problem for the water-cooled. I always thought it was the O-ring
> that sits under the sensor. Replaced that, but it still leaked. Before I
> invested in a new sensor or caps or seals for same, I had the unit checked
> under pressure. Sure enough, it's a hairline crack in the tank.
>
> For all those in warmer climates, who have a persistent leaking problem
> (from around the coolant reservoir), check your reservoir.
>
> Chris
> vanagon list admin
>