I have a 1986 F350, 2wd with a 460. Has in tank fuel pumps. It has a selector switch on the dash. According to what I have read the rear tank is the default tank if something goes wrong with switches. We ran it on the rear tank for a short time but then it stopped getting any fuel to carburetor. I am going to drop the rear tank and replace the fuel pump. Is there a way to test if the tank select switch is bad or the tank selector valve? Any help would be appreciated and the best place to buy truck parts?

 

You posted in the wrong place. Your question was most likely missed by everyone. You need to post in the "main 80-86 truck" forum, not this FAQ section.
Good luck.

 

You should try energizing the pump before condemning it.
It could be the relay, oil pressure switch, inertia switch, fuse, or fusible link.

None of these are nearly as involved as pulling the tank to change the pump.

 

Amen! Schematics shown here: Electric Fuel Pump Control - ???Gary's Garagemahal.