[TR] Electric Fuel pump tr3a

[Randall]

The idea is that it is safer to have some device to stop the pump in case of
an accident.

Of course you also want it controlled by the ignition switch (so it doesn't
run with the switch off), and IMO fused.

Lots of cars (including Triumphs with an electric pump from the factory) use
an inertia switch.  Some use a device that senses whether the engine is
turning (by monitoring the action of the points).  Or, it's not that
difficult to add an oil pressure switch to a TR3 (by drilling and tapping
the filter head).

A little quick poking about shows a modern inertia switch at AutoZone for
$31, or the 3-prong oil pressure switch from TRF for $20.  I didn't bother
looking up the relay that monitors the points, but I know it was used on VW
Rabbits with Bosch fuel injection (74 I think).

-- Randall