My experience has been when the hairline cracks develop, it's time to
replace the tank.  There are some quick fixes to get to down the road,
but only just that.  Tried it on my 81 Diesel Pickup a few years back and
didn't get very far.  Vanagons IMHO are even little more fragile come to
think of it.

We carry them in stock for about $37.40 (I think VW gets about $48 for
them now)  Fits 83-85 Models

Order Part Number 025-121-403A (Replaces old VW# and casting# on tank
025-121-407)

If the cap is suspect, we got them too - $9.95  Part Number 025-121-321B

Both items OE VW

Jim
BusBoys1@juno.com
http://www.bus-boys.com
800-792-2697
916-244-0933 FAX