Hi,
This has been bugging me since the first time I put gas in my '86 F250. I have to let the gas flow in VERY slowly or the back pressure shuts off the gas pump. Is there a breather plugged or something? It sucks when it's 20 degrees and I'm watching the gas trickle into the tank for 10 minutes while fueling up.
ScottyB.

 

Me an you are in the same boat! my f-150 does the same thing, but it spits the gas back out the filler tube if you fill it too fast. i think its the vent tube on mine thats stopped up or something else, but i haven't had a chance to check it yet. just might give you an idea on how to correct it. (the vent tube should run about paralelle to the filler tube, under the bed, if you have a single tank, duals i have no idea)

Hope this helps!

 

Check the filler tube under the bed. Make sure it isn't kinked or bent, and check the vent tube also. Try using a piece of stiff wire, bend the end into a tight loop to prevent snagging, and gently push it down into the tube through the filler. It shouldn't give much resistance, if it does, either the hose is collapsed or there is something in there. I had someone stuff a rag into the filler on my 78, so it wouldn't take gas at all.

Jared

 

I say drop the tank and make sur the burp tube is there...My 85 takes gas at full flow.

 

I have this issue too in both tanks on my 83 F250. It looks like (to me) that there is a sag between the tank and where the clamp attaches the filler neck to the L shaped holder from the body. I figured the gas was hitting that puddle and splashing around. I have siphoned the tank dry before and I know there are a few obsticles the siphoning hose hits on it's way down (nothing blocks it completely). I think one is where the wide tubing meets the gas tank, but there is (i think another one also)

 

My '86 f250 used to do the exact same thing. I've found that if I don't put the nozzle all the way into the filler, it gives it more room to breath, thus, not causing backflow. Just an idea...

 

 

my 83 f100 does the same thing. the rear tank (only one left on the truck) will shut off the pump in less than 2 seconds. i have to move the gas pump nozzle up a little to make an air gap so it will fill at full speed. ive learned to live with it- theres a lot of other problems worse than that on the truck.

 

My 1980 used to do the same thing. When I changed beds, I discovered there is a small plastic pipe inside the filler pipe. This plastic pipe has a clip that holds it in place inside the big pipe. The small pipe had come out of the clip, and was just riding around in the filler. When I put everything back together, I installed the small pipe like it was supposed to be and my serious filling problems went away. I still have to pull the fuel nozzle out a little bit like the other posters said, but it definitely flows better than it did before. I think the fuel was splashing against the small pipe, and triggering the fuel shut off in the nozzle.

 

Had the same problem, the pipe inside the filler yube had come loose and slid down a little in the filler tube. When the fuel was flowing fast it would hit the end of the pipe instead of going inside it, when this happened it would splash up and shut of the fuel flow. I removed the filler line and repositioned and clipped the tube back in place. I made sure when I reinstalled the filler that the pipe was slid up snug against the fill opening. No problems since.
T. Roberts
UFD Local 1147

 

I have the same problem with fuel backing-up and shuting-off the pump on my '83 F-250 460 w/ dual tanks. I figuered it had to be a venting problem (happens w/ both tanks). Took both filler hoses off and checked the vent tubes inside the filler hoses and can find no blockage. However, I notice that the small vent tubes appear to be made of different material than the bigger filler hoses they are inside of. Wondering if they got kinked or pinched-off when the box was changed. Next step will be to try different hose, but hard to find used (expensive new). Any help?

 

Use a later filler neck that has the fuel flowing in the inner tube and the vapor flowing back up between the inner & outer tubes. The inner tube on them is much thicker & larger, and mine has had no problems since I swapped. I originally did it so I could have the cap on the tether , but when I put the locking cap on, I lost that feature.

 

ive had the tank out b4 and i know the vapor tube that runs to the charcoal canister is hooked up...and the smalltube inside the rubber filler neck i removed uh oh i believe that the small tube is meant to channel the main fuel flow from the nozzle through this and into the tank,and let excess air vent around the outside of the small tube...i can feel the rubber filler all the way from the tank up to the back of the body where it goes on the nozzle thing and there are no major kinks...a very slight one where the rubber hose goes over the frame...anyway there is something hard probly part of the thing you put the nozzle in in the filler right at the top and it goes in maybe 2 inches or so from where the rubber filler goes to the body..i think it may be messed up but havent changed it yet...