78 F250 Dual tank fuel system
 

Help!! I cant find a wiring diagram for my fuel sys ..I'm real tired of my fuel guage not working as its my daily driver..

Thanks to all ,Thunder...

78 F250 Dual tank fuel system
 

Eric, have you thought to trace the wire by hand, they usually don't change the color code. You were not specific about why you needed help. The guages rarely go bad. Does either tank work?


John

78 F250 Dual tank fuel system
 

I'm using the main tank now , tried to replace the fuse for the switching system,it blows even with an overrated fuse.I could trace them by hand ,but it would sure help to have a diagram to go by.

Thanks for responding ....

78 F250 Dual tank fuel system
 

Man you have a direct short. You might as well start at the tanks and inspect the sending wire. There is a naked spot somewhere, and I'll bet on the chassis. As soon as you can find it either wrap it with tape or cut it and put in a coupler, then try a new proper size fuse. A fuse is a safty device, it lets you know that there is a problem. Adding a larger fuse is a hazzard and can cause more problems.

Your problem shouldn't be hard to find.

John

78 F250 Dual tank fuel system
 

My guess would be the tank selector solenoid. It's located in the frame rail just ahead of the front tank. Unplug it, put a new fuse in and try the switch. If the fuse holds, it's the solenoid.

Only about 5' of wire to inspect from there to the engine bay. Most of it's easy to get at.

Roger