Another fuel pump question

[boris_thespider]

Do I run my fuel pump to "hot all the time" battery connection or does it only get power when the ignition key is on? Thanks..

Mike

[55312]

Key only!

Tim

[wtm442]

Agree - it should be "Key Power". Also, if you really want to be safe and you race the Cobra, install an adjustable pressure switch into the line to the oil pressure gauge. Then wire the oil pressure switch into the electric fuel pump circuit so it only supplies power when the oil pressure is above what pressure you dial into the switch.

[Ron61]

Definitely Key Only and as Warren said, you can also use an oil pressure switch in the circuit. I ran mine at 5 pounds. I also ran a lead to a toggle switch on the dash that I could shut the pump off as there will be times when you may want to look for a keyed hot lead and not have it running.

Ron

[boris_thespider]

Thanks guys... running it off the key was my first thought. I am going to use a kill switch on the pump too.

Mike

[sobz]

Does anyone have a diagram on how to hook up the electric fuel pump to the oil press. switch and then to a cut off switch.

Thanks,

Bob

[RallySnake]

Bob,

I have been improving my car for 19 years. I am an electronic and computer technitian and have learned a few tricks that I have applied to my car.

I wouldn't use the oil pressure switch. Sometimes, it may difficult to start the car if the system is dry. You can make an arguement that there's always gas in the carb, but I have had problems with this. I do use an inertia switch from a Mustang instead. If you are in an accident, the fuel pump is cut off immediately, not after the pressure drops.

I wired a relay (located in the engine compartment) to the ignition switch. The relay takes the current load off the switch and powers the fuel pump and MSD ignition. This relay is also wired through the alarm system so that the car can only be started after the alarm is disabled. The Clifford alarm system also pops either door open. This is very useful if the top is on the car.

A second relay from the ignition switch powers up all the circuits that I want to activate only when the car is running: wipers, radar detector, back up lights, heaters, radiator fan and etc.

You really want to set up a master power off (kill) switch in the big wire from the battery to the chassis ground. You could put this in a hidden location, but they are large and it's not easy.

I'll see if I can find a diagram for you.

Paul