At the risk of interrupting your beer.....   ;)

Did you find that the pump noise was worse at higher altitudes?

I posted to the list of this, but on a long trip last Summer, waaaaay
up in the mountains,
my '81 developed vapour lock causing the engine to stall. Pump was
quite noisy prior. After that, it drove fine at sea level or slightly
higher.

When i got home, at sea level, as per the Bentley test I did a quick
test of the evap system by blowing into the small tube that connects
to the inlet of charcoal filter. I could hear a slight "hissing" sound
near the fuel tank. There should obviously be no leaks between this
small tube and the rest of the evap system. How the bus developed a
case of vapour lock is a bit of a mystery.

My working theory at the time of vapour lock was that the evap system
was not venting correctly. Although I suspect there's a flaw in the
evap system, (the "hiss") I'm curious if altitude affects a marginal
part in the evap system and-or fuel tank.

Neil.

On 12/5/14, Geneva Saint-Amour <genevasaintamour@hotmail.com> wrote:

> Stuart-
> We drilled a hole in each tank. The fuel pump is back to peaceful pumping.
> No squealing.
> Muchas gracias. Now for that beer!

--
Neil n

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