wrote in message
...
On Sat, 26 Jan 2013 10:42:04 -0700, Tony Hwang
wrote:



Existential Angst wrote:


So basically, the Q is:
How practical is using the vehicle's fuel pump as a transfer pump?
Even
for, say, giving a stranded motorist a cupla gallons, without having to
lug

Hi,
Gas coming out of fuel pump is pressurized(after passing thru regulator)
can you manage that w/o spilling gas all over? I'd rather
siphon the gas.
Depends on the vehicle. Older EFI units had return system regulators 0
so fuel was pressurized BEFORE the regulator. MAny new units are
return-less - regulator in the pum asembly. The fuel is pressurizwd
with the system intact. If you have a tap-off like the schrader test
fitting open.all you get is high volume as the pressure can not build.

And good luck siphoning from most relatively current vehicles.

When I was scrapping my 1990 Mazda 929S, I tried to siphon off the remaining
gas.... couldn't do it in any non-destructive way.

No return line would proly make this unworkable with the engine running --
which would not be a biggie if the pump can be otherwise energized. It
seems preferable to be able to transfer gasoline without the engine running.
--
EA