I've got a minor fuel leak somewhere at the top of the tank. I noticed it a few fill-ups ago but haven't really had the time to drop the tank and check it out.

Basically, here's the problem: when filling, after the tank is pretty much full, I'll notice a few drops on the ground under the front of the tank. Sometimes it happens right before the pump auto-clicks off ('full tank' auto shutoff), and sometimes it happens as I'm trying to squeeze the last few gallons in. For some reason, around here the pumps seem to stop at about 16 gallons and I usually fill up when she's pretty much empty. I normally can get another 2 gallons (give or take a penny) in after first click. More or less, the tank only leaks when almost full and pushing the last few drops in.

It used to go without dripping at all and I would fill it until I could pretty much see fuel in the filler neck, now it won't get quite up there. I just fill until she just starts dripping.

The truck does NOT leak when it's sitting, just when fueling. There is no gas smell and no drips anywhere (even when leaving a sheet of cardboard underneath.


What I'm wondering is if anyone has had similar problems. Also, any suggestions on what could be wrong? I'd really prefer to do this without dropping the tank, but I doubt that's a possibility. I am sure if I'm determined enough, I could drop the tank and replace it in a day easy. I won't be able to wait for parts, if it's not in stock for some reason.

Alright. Enough rambling. Has anyone had an issue like that? What parts were required? Any thoughts/comments/suggestions? Anything that can be done to fix the problem without dropping the tank? ETC. Also, it's an 84 F150 single tank styleside.


Thanks to everyone who helps.

 

You'll have to pull the tank to see, unless your pulling the bed. You'll most likely find pinholes in the very top of the tank around the sender.

 

I had the same problem. It turned out to be the small tube going to the carbon canister from above the tank. I took it off and reinserted it and no more problems. I also replaced the hose attached to the tube since it was rotted. I was able to do this without dropping the tank.

 

Alright. Thanks, RL, I'll give that a shot tomorrow. If it doesn't seem to work, I'll drop the tank when I'm lower on fuel.

 

For whatever it's worth, I checked that stuff out the other day.

I pulled and reinserted the valve attached to the tube/line going to the can.

I also replaced the rubber hose that goes from the sender to the steel fuel line.
I filled it up tonight and no drips. Seems to have worked. I'll keep an eye on it to see what happens, but hopefully it'll be more permanent. Thanks again, RL.


By the way, the sending unit is easily accessible from under the truck without dropping the tank or removing the bed.

 

Really, or is that last sentence sarcasm?

 

Its easily accessible until he puts a hammer up there to turn the lock ring LOL.

 

No. It was not sarcasm, and if you're not a total idiot, you can get in there without a problem. Even with said "hammer".

 

Cool, Glad it worked out.