Re: Dual gas tanks and Projection

["Tom Harais" <tjhemh@domain.elided>]

Allan:

I've used an electric fuel pump set up to run by "sucking' through an
electric switch so that I could "suck" from either tank, and it worked.
Here's what to watch out for: My switch said right on it: "DO NOT
PRESSURIZE INTAKE PORTS" as well as "MAXIMUM VACUUM AT OUTLET, 8PSI". My
interpretation of those instructions was, 1) Don't put the pump between the
tanks and the switch, and 2) if your pump puts out more than 8 PSI it will
probably "suck" more than 8PSI vacuum so don't use that pump with this
switch.

What I was assuming is, if you pressurize the intake ports, then the fuel
will probably flow from one tank to the other not just from one tank to the
engine and; with more than 8 PSI suction (as in most FI systems these days
which run at 30 PSI or so) the suction would probably overcome either or
both intakes ports valves and suck from both tanks.

Tom H.

P.S. I still have the mechanical pump in the circuit between the electric
and the carb and I only use the electric when there is a problem with cold
starting after sitting for days or when there is "vapor lock" potential.
Interesting enough, the electric pushes right through the mechanical, even
though everyon said would.