Electric Fuel Pump Connected to Oil Pressure Sender?

[LaGrasta]

My electric fuel pump is tied into switched power and has worked perfect for years. The downside is when I turn the key just to listen to the stereo, the pump runs. It also runs if the engine dies, but the key is still on.

Finally this past weekend, I tied into the sender as was instructed by someone on here sometime ago. I honestly don't remember who. After some soldering and rewire all that happened is the oil pressure light stayed on and the car wouldn't start after the bowl emptied. It basically never pumped. What gives? Did I do it wrong or was the advice wrong?

 

[fordconvert]

Sounds like you may have wired it wrong. I would think a relay would be needed because most fuel pumps draw more than a typical oil pressure switch can handle. A relay would have other benefits like you could also hook it up to run the pump while cranking.

 

[addo]

That's right. The sender goes off once the motor starts - so it would keep the pump switched off.

 

[Lazy JW]

... was the advice wrong?

Yup

 

[fordconvert]

I didnt even think about the part of having a standard switch... it would turn off when there was pressure. I was thinking of the 3 pin GM ones that also drive the choke.

 

[Shrinkdude]

I have mine on a relay activated when the key is on. I put a regular toggle switch in the glove box to turn off the pump when I want to.

 

[wallaka]

http://www.holley.com/12-810.asp

Fuel Pump Safety Pressure Switch

Around 20 bucks.

 

[jahearne]

I have mine on a relay activated when the key is on. I put a regular toggle switch in the glove box to turn off the pump when I want to.

I did something similar. Have a toggle to turn the fuel pump on to prime the triple carbs before the car starts. A 30 amp relay switch comes off oil pressure safety switch.

 

[MustangSix]

The chevy vega had a three contact oil pressure switch. A common, One normally off, one normally on. When the engine switched on, the normally on contact lit the oil pressure light. As pressure came up, the normally off side turned on the fuel pump and the light would go off.

You should still be able to get one of these for just a couple of bucks.

 

[falcon fanatic]

Anthony,
Whichever way you go, use a relay. I've burned through two "oil safety switches" from summit by hooking them up directly to the pump. Can't handle the draw. you should be able to just attach a relay directly to the sender. Use one that opens the circuit when it has power (oil light on = pump off), and closes the circuit when it loses power (oil light off = pump on). wouldn't that work?

 

[LaGrasta]

thanks everyone.

 

[Williboy]

I have an article saved somewhere that said to also wire the pump to the R terminal on the starter solenoid to provide power to the pump while starting

 

[LaGrasta]

The chevy vega had a three contact oil pressure switch. A common, One normally off, one normally on. When the engine switched on, the normally on contact lit the oil pressure light. As pressure came up, the normally off side turned on the fuel pump and the light would go off.

You should still be able to get one of these for just a couple of bucks.

THANK YOU! This Vega unit is the ticket. After searching norms like Summit, Jegs, & Google, the Vega part was about a third lower in cost. I had to order it from AutoZone as it's not stocked, but $12 later, it's mine and no shipping charges either. Thanks for the tip. Now to finally install it...