Wiring two fuel tanks and ONE fuel gauge to the same switch?

**pcrussell50** · 03-17-2025, 02:18 PM

This is the setup I have.

One switch I can flip left and right to pull from the port or starboard tank, AND when I do, the one fuel gauge in the dash, reads the tank selected.

It’s all up and working. Only the back, of the dash is a wiring nightmare. I plan to clean it up by a lot. BUT in case I f-it up… I can no longer find the schematic I used, along with the type of switch I need (it has six lugs on the back), to replicate the work.

Anyone point me to the right schematic/diagram? And the right switch?(DPDT?) Also where do you get quality toggle switches? Amazon has tons but I don’t know a good brand from not.

-Peter

**WaterZebra** · 03-17-2025, 03:34 PM

Originally Posted by pcrussell50

This is the setup I have.

One switch I can flip left and right to pull from the port or starboard tank, AND when I do, the one fuel gauge in the dash, reads the tank selected.

It’s all up and working. Only the back, of the dash is a wiring nightmare. I plan to clean it up by a lot. BUT in case I f-it up… I can no longer find the schematic I used, along with the type of switch I need (it has six lugs on the back), to replicate the work.

Anyone point me to the right schematic/diagram? And the right switch?(DPDT?) Also where do you get quality toggle switches? Amazon has tons but I don’t know a good brand from not.

-Peter

What do you mean by "pull"? Fuel level is one thing but fuel flow gets complicated (electric valves, etc).

Post a pic of your switch (both sides).
- Ground ..............common
- Positive power supply to sending units
- Sending units power (each (+) line to toggle switch circuits)
- Toggle switch line out to fuel gauge (+)

**pcrussell50** · 03-17-2025, 05:51 PM

Originally Posted by WaterZebra

What do you mean by "pull"? Fuel level is one thing but fuel flow gets complicated (electric valves, etc).

Post a pic of your switch (both sides).
- Ground ..............common
- Positive power supply to sending units
- Sending units power (each (+) line to toggle switch circuits)
- Toggle switch line out to fuel gauge (+)

the engine driven fuel pump draws fuel from whichever tank is selected. Also, the fuel gauge reads whichever tank is selcted. And it’s all wired through the switch.

I’m searching for a diagram that tells me how to wire the switch.

-Peter

**FUJIMO** · 03-28-2025, 08:55 PM

...take photos...

**David - WI** · 03-28-2025, 09:32 PM

Most of the electric dual-tank valves have a switch built in to switch the gauge to the "active" tank. EFI dual-tank valves switch the supply, return, and guage together.