Hey Guys quick question, I'm wiring an electric fuel pump through an oil pressure switch as a safety cutoff for a customers car... engine is a 440, can I install the switch into the extra port in the rear of the block beside the regular oil pressure switch location or should I use an adapter and run it off the same port ? Is there a better location I'm missing ?

Or.... I don't suppose there's one sending unit/switch "all in one" out there that will read resistance for the gauges and act as a switch for the fuel pump ??

thanks...

Mount and run it where you like There is a similar post in the General section about using a wiring diagram for a low pressure oil shut off circuit using a Hobbs switch

We have a T screwed into each port on the back of the block Left side feeds Left head and also oil pressure gauge and the Right side feeds Right head and fuel pump cut off switch. These are 440-1 heads with the external feed lines of course.

thanks guys...

You need to run separate switches for this application. The fuel pump cutoff switch is a normally open (on-off) type pressure switch. In other words, it is an open circuit until the oil pressure reaches a set amount like 15 psi etc.

Be sure you run a relay and use the low oil pressure switch on the "trigger" side of the relay. Do not run the main fuel pump voltage/amperage through the cutoff switch. It will fry it in a short time.

I also ran a bypass toggle switch inside the car, so I can run the fuel pump without the motor running to prime the carbs etc.

A motor will run a long time after the pump shuts off. If this was in the middle of a full throttle run, the killing of the fuel probably saves nothing.

I would prefer a large light and if it comes on, you kill the power instantly shutting the motor down. In lieu of that, you could wire the ignition feed circuit through the pressure switch. You lose oil pressure, the motors needs to quit NOW, not after it runs out of fuel