I'd suggest some Vanagons still have the original braided hose from
vapour expansion
tanks to fuel tank.

The expansion tank gets hammered with road debris, water etc. The plastic gets
softer and can crack.

If the grommet at "roll over" valve is bad, missing or otherwise
messed up, water and
debris will get in that tank and likely into fuel tank.

BTDT

Images of a failing fuel expansion tank and results of failed seal at valve:

https://picasaweb.google.com/musomuso/VanagonGasEVAP#5989243204644619698

On 7/17/16, Roy Nicholl <RNicholl@nbnet.nb.ca> wrote:

> There is an expansion tank in each wheel well and not improbably that one of
> the lines to/from the expansion tank is cracked - or simply disconnected.
> When I bought the hyena, the nipple on the expansion tank cap on the
> driver’s side was broken and the line was tucked in-between the tank and the
> metal of the wheel well.
>

-- 
Neil n

Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>

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