Auxiliary Fuel Pump

[ocsddep]

I have an auxiliary fuel pump on my 67 109 NADA. It is located below the passenger seat. It has 2 toggle switched hooked up to it. There is an auxiliary fuel tank also below the passenger seat. I don't know if this was a factory option or someone installed it, but it looks very professional. When I turn one of the toggle switches, I do hear a clicking sound coming from the pump. I can't tell what the second toggle switch is for.

I looked in the manuals and they do reference this pump. It is an SU pump. If anyone is familiar with it and how it works, I would really appreciate any insight. This forum is my only hope in keeping this truck running. There is another fuel pump by the carburetor and it is definitely an aftermarket one. I am wondering if one the toggle switches activate the pump to pump fuel from the main tank to the aux tank and the second switch activates the pump to send fuel to the carburetor. Just guessing here.

Thanks in advance!

Ray

[stomper]

You never can be sure what a prior owner has thought up, or even why. That being said, one toggle switch should run the fuel pump, and the other should switch over the fuel guage to read the fuel level in the aux. tank.

Don't know why you would have a fuel pump near the carb.

[antichrist]

This is similar to the stock fuel pump on the NADA 109

[ocsddep]

The pump in the pic looks exactly like mine. I didn't know they were still available.

I am not sure if the other toggle switch is for the gauge since the aux tank doesn't have a float or anyway to measure the fuel in it.

I am going to drain the aux tank and turn on the pump to see if it moves the fuel from the main to the aux.

The pump below the carb is a NAPA fuel pump that constantly on. It ticks all the time. I have feeling the original SU is disconnected. I guess I have to trace the fuel lines out of and see where they go.

[antichrist]

If it's plumbed right (switchover valve before the pump) you only need one fuel pump.
Nisonger used to sell and rebuild them IIRC. They had an upgraded version that had a lifetime warranty.