Electric fuel pumps are all designed to push, not pull, the fuel.
Therefore they have to be mounted as low as possible, so they have
gravity feed. The second reason for a lower mounting point (like down
on the frame under the floor pan) is that some fuel systems have very
small pin-hole and smaller leaks, which are small enough that they will
not leak a fluid, such as gasoline, but will leak air. In such a case,
a higher mounted pump will suck air through the leak point in preference
to or in addition to the gasoline. Such a leak, which does not show a
fluid dripping, can drive you batty! In any case, for all reasons, you
are far better off with your pump mounted at the lowest point you can find.
Bill Brewer wrote:
> I've been running a modern electric fuel pump in theold TR3 for years.
>Recently, I moved the fuel pump from down near the spin on oil filter to up
>on the fender just below the curve. This was to make inspecting the filter
>easier and get it away from interfering with changing the oil filter. I
>believe the Bob Schaller recommended it be installed here in his book.
> Now, weeks later the car has started periodically sputtering. It could
>be a myriad of other things. The points look like they need attention and I
>have a Pertronix unit on the way. Anyway, I was wondering if it could be
>fuel supply because now the pump and filter are a bit higher up in relation
>to the gas tank level.
> Has anyone had fuel starvation with their pump mounted in the same
>location?
>
> Bill Brewer
> Tehachapi, CA
>
>
>
>
>
Electric fuel pumps are all designed to push, not pull, the fuel.
Therefore they have to be mounted as low as possible, so they have
gravity feed. The second reason for a lower mounting point (like down
on the frame under the floor pan) is that some fuel systems have very
small pin-hole and smaller leaks, which are small enough that they will
not leak a fluid, such as gasoline, but will leak air. In such a case,
a higher mounted pump will suck air through the leak point in preference
to or in addition to the gasoline. Such a leak, which does not show a
fluid dripping, can drive you batty! In any case, for all reasons, you
are far better off with your pump mounted at the lowest point you can find.
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