I can only get 1 of my gas tanks to feed to my engine (back tank) and the other will not feed. How or what must I do to make this work again. What should I check. Please help.

 

Need help solving my problem with my double gas tanks on mu 1981 F100. The back tank will feed the gas to the engine but the front tank will not feed the engine when I switch to that tank. I have gas in the tank. Please help.

 

Two threads on the same topic have been merged together.

 

Check the lines and the valve along the driver's side frame rail, about under the driver's door. Make sure the front tank lines are hooked up and that the valve is switching.

 

The rear tank is default on the selector valve solenoid located on the Drivers side inner frame rail. It's means of ground is where it attaches to the frame. There should be one brown/white stripe wire feeding into it.

With the tank selector switch in the dash switched to Front, you should be getting power to this wire at the selector solenoid. Use a test lamp, with the ignition switch placed in run with the engine off. If power at the Brown/White stripe wire, try cleaning the ground to the solenoid by unbolting it from the frame and using sand paper to make metal to metal contact, then reattach the solenoid. You can use dielectric grease to help fight future rust issues where the solenoid and frame connect.

If you have power at the Brown/white stripe wire, and cleaning the solenoid contact to the frame doesn't work, you most likely need a new Fuel Tank selector solenoid.