Won't start using aux tank

[Broncobowsher]

I wired mine to an on only circuit. There's no reason to energize the solenoid when the engine isn't running.

But is your "on" circuit actually powered up during engine crank? You might be surprised to find it isn't, or sometimes isn't. The ignition doesn't care as it is getting the bypass from the "I" wire off the solenoid. So it will start even if the run terminal is dead in crank.

 

[Bronco808]

Ok so I drove Ginger to work yesterday with it switched to the aux tank and I made it round-trip. The fuel gauge also went down accordingly so I know it was running off the aux tank. Thanks everyone!