Mike, This is a common problem with the Vanagon as I learned when I went
through the same thing. The seal may be in great shape, but in all liklihood
it is pulled away from the body of the van in at least one place. Look very
carefully all the way around the seal. On my Vanagon, it happened in the
upper, passenger-side corner. The fix is very simple. I simply ran a bead of
*clear* silicon caulk (basic household outdoor type) all the way around
(underneath) the seal. No puddles since. You may have to wait for a string
of successive dry days to allow the water that's already in there to dry.

Good luck & stay dry :)
Pat

>I found a large puddle of water on the driver's side floor mat of my '84
>Westy this morning.  Having had heavy rain the night before, I checked all
>the windows, they were all closed.  I did notice a small amount of water
>collecting on the dash next to the lower left hand side of the windshield.
>The water seems to have come from under the seal.  The Windshield seal is in
>great shape, and there is no visible rust around the outside of the seal.  I
>was wondering if there was a sealant I could use around the seal to keep
>this from happening again.   I really don't want to replace the seal if I
>don't have to.