I going to wire the electrical fuel pump through my thatcham Cat 2 Imobilieser so that it is part of the security system.
Should I put either a " deadman switch " or an inertia switch in aswell. so I can shut off the pump if anything happens instead of "as long as" the ignitions on.

What does the SVA manuals say about this?

If the answer is YES - What sort of donor car would have a inertia switch and what does it look like and where on the donor is it located ( Back , Engine bay, underneath, Boot, on top of tank etc).,

inertia switches are used to shut off the pump if you have an accident to stop the efi pump.

I think you should wire the output via a relay cos a pump draws about 10a.

mk3 granada (80s prior to frog scorpio) have them fitted at the rear of the car I think between tank and rear bumper/valence. A black box about 2 ins square with a white button coming out top.

It may be mounted so its acessable from the boot floor - its a long time since i took mine out.

get the connector and length of cable too

atb

steve

I got my inertia switch out of a Rover 200/400.

It's located inside the Rover cabin just behind the stereo/ashtray/heater controls in the centre of the dash. There are two types;

1) Square box design in early models (pre 1994 ish)

2) Later cars have a much smaller/neater design as seen in Caterhams and the like.

It cost a fiver from the local scrapyard - well worth it in the event of a bump.

When removing the switch from the car pull some of the wiring loom through and cut off a foot of cable and the special connector.

On a slightly different note, is it worth fitting one of these if your running an eletric pump on weber's, as the pressure is much lower?

Steve

Wire it through an oil pressure switch and relay. If the accident severs the fuel line the engine will stop, pressure drops and the fuel pump cuts off. If the accident is light enough that the fuel system/engine is undamaged then the car will still run.

Honda's were, and my still be, set up this way.

the late rover 200/400 inertia cut out switch is a neat (as jag states)version and this is what westfield use. they wire it inline with the power wires to the fuel pump, no relay.obviously the switch can handle the power required of the pump (mine was on a SEIght westfield).
great idea to have one for the small additional cost.

Rover SD1s are also wired up so the fuel pump is shut off by low oil pressure. Seems like a sound idea.

Would that not pose a problem as you may not have oil pressure until the engine has cranked over serveral times. Only then would the fuel pump kick in.

I know you would have the fuel in the carb bowls but would that be enough?

Most cars use the starter circuit to run the fuel pump until oil pressure is achieved then the main circuits take over.

Some but not all Rovers use an oil switch with reversed logic from other cars ie normally off, oil pressure closes the contacts., oil light is wired through a relay.