> Halon, has oxygen starvation properties.
> When the fire is out it is out.
> Unless of course, some mad man, would be dumb enough to allow the
> vehicle in question, to continue running and stoke the fire again.

that's precisely the problem...

having read many Vanagon fire stories the common thread seems to be that
they don't notice the fire for some time... unusually not until the engine
is running ruff and they 'happen' to look in the mirror and see the smoke
and/or flames coming out the rear vents...

So I would be concerned that an automatic halon system would put the fire
out without the driver being aware that there was a fire... he keeps
driving, the halon blows out the bottom of the engine compartment... but
engine is still running, fuel still pumping so the fire starts up again...
but now the halon canisters have been spent so the fire continues this time
until the driver 'happens to notice it'...

of course this could maybe be solved with a halon system that had an alarm
to alert the driver... but still, at 60 mph the halon would blow out pretty
quickly and the fire could possibly start again before the driver even got
pulled over to the side of the road... in that event I'd want a conventional
fire extinguisher to back up the  halon...

another possibility might be to add a cut off relay to the fuel pump power
supply,

In any event, I wouldn't expect the halon to be as effective in all
situations in a Vanagon as it is in a boat.

hey, it's just my opinion as to what might happen...
do what you want...

Bill