Hi Stuart. Very good point. A check valve seal may be at fault.

As you know, it's hidden up there in the wheel well, with all the dirt.    ;)
All other seals, hoses etc. are in good shape as I resealed the tank
not that long ago.

NOT saying this is the same part, but the VC tank has a similar or
same marking on it as the tank I installed: http://tinyurl.com/mbw2nmc
My amateur skills aside, (aligning the large type filler neck is a
small pita), the filler neck hole in my tank didn't exactly line up
with the hole in frame which, in part, caused a leak at the filler
pipe to tank grommet. Images:

before filler neck re-align
http://tinyurl.com/lxvqzp3
after
http://tinyurl.com/mu7ll6h
not a great shot, but kind of shows poor tank to frame hole alignment
http://tinyurl.com/l2ngelr

I replaced that grommet and re-aligned the filler pipe parts. It
hasn't leaked since.

Really appreciate the suggestion of check valve seals. I wondered of
the evap system but that may be the weak link.

Neil.

On 3/5/14, Stuart MacMillan <stuartmacm@gmail.com> wrote:

>..... check the two vent tanks in the
> wheel wells.  The check valve seal can soften and fail, and the tanks can
> crack.

> .... Frankly, given all the junk in your tank, for the price of
> $175 I'd replace it:
> http://www.van-cafe.com/home/van/page_1178_1457/fuel-gas-tank.html

--
Neil n

Blog: tubaneil.blogspot.ca

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