I'm having a problem with my gas tank spitting fuel back up when i'm trying to fuel up my '80 F-100 2wd, single tank. It happens when I squeeze the gas nozzle to fill as fast as possible, and it happens every time. As long as i fill it up very slowly it's fine, but if i pull the trigger all the way it rushes back out and shuts the pump off, and spits a little fuel out from somewhere behind the bed wall between the tank and filler opening. This is really irritating since i have to sit at the pump forever barely holding the handle at all. Any help is appreciated.

 

You have a hose thats clogged thats connected to the fill tank, its a small hose, next to it. If its not venting when you fill up, it will do exacty that, also check the charcoal canister that goes from the tank to the canister. Air has to leave the tank as you fill it up, if it doesn't do it well, someplace a vent pipe is blocked...

 

One of the hoses probably is clogged. No telling what kind of crap is in that tank. Thanks

 

Those little vent hoses don't take a lot to kink or twist when installing or reinstalling. We had a truck come back from the body shop and develope the "burping" problem. Especially bad with diesels using the larger filler nozzles.

 

It's likely not a plugged or kinked hose. It is just a poor design of the filler tube from the factory. Don't stick the nozzle all the way in the neck of the tank.
Every Ford truck that I've known or owned from that time period has this problem.

Try pulling the nozzle out a bit and hold it there while filling at a slower rate.
Even new Tauri have this problem and so do a lot of newer f-150's. Even my wife's mercury has this problem when it gets hot out.
There isn't much you can do about it

 

I have this problem and it is very pronounced with the flatbed setup I have. I have a very keen eye for gas stations with aprons that slope away from the pumps or pumps that are on a slope, then I will park to an angle to the pumps. If the tank is empty and it is hot out I start slow, the gasoline tends to vaporize very quickly until the tank cools off. When doing it this way I can go full tilt.