Tapping into Oil Pressure Wire for electric fuel pump?

[Fiat88]

Still can't decide what to do for my electric fuel pump situation. Right now its wired so it always on when the ignition is turned on. Is there anyway I can wire it up so it gets a signal from the oil pressure switch? Or do I have to buy a special oil pressure fuel cutoff switch?

I need to wire a relay in anyway as the OP just ran it off the fuse box.

[baltobernie]

There is probably a specialty relay designed for this purpose. To make your own circuit, you'll need two relays; a normally-closed relay to power the pump, and a time-delay relay before it, so that you can get the engine running. After a predetermined period the relay times out, and if the O/P switch closes, the signal drops out of the power relay and the pump stops.

My question is, Why bother? The Fiat oil pump is a pretty robust item. If the pickup doesn't get broken, you should see a very gradual decrease of oil pressure over many, many thousands of miles. The O/E pump will probably outlast the piston rings and main bearings, so a full rebuild should include a new pump, but other than that ...

If you are especially nervous, you could always replace the Oil Fail lamp with a very bright bulb (here's one instance where an LED bulb would be actually useful). The gauge and lamp are smack dab in the center of the cluster; tough to miss.

[Schnauzer]

My 76 is wired just like you are proposing. Low oil pressure light sender is in the ground side of the fuel pump circuit.

Jim

[bradartigue]

Install mechanical fuel pump. Delete electric fuel pump. Enjoy 30 years of service instead of 3.

[manoa matt]

"Install mechanical fuel pump. Delete electric fuel pump. Enjoy 30 years of service instead of 3."

I aggree in principal, but recent mech pumps are no where near the quality of the originals. I work on an old ladie's car, she is in her 80's. Bought the car new from the dealer and has driven it every day ever since. 2 years ago she wanted me to replace the mechanical fuel pump pre-emptively as it was over 10 years old. The new mechanical fuel pump lasted about one month. One of the tiny internal check valves was bad. I put the old one back on and its been going every day for the last 2 years which its age is now 12 years old.

Sadly I find myself installing more and more 30+ year old OEM original parts from parts cars as they are more reliable that what is currently being offered. Especially anything made of rubber or that has a rubber component inside.