My truck just learned a new trick... while filling the front tank... put nozzle in fill tube click on full... backs up and overflows within a few seconds !!! It never did that before If I fill it slow it doesn't do it ... Rear tank fills just fine as it always has .... Open to suggestions and comments ...PLEASE !!!! Dave

 

One of your tank vent tubes is blocked.

 

Question... does each tank have it's own dedicated vent line ??? Are the vent tube inside the fill tube or outside... kinda wanna get an idea what I'm looking for ... Thanks ... Dave

 

It's inside the fill tube, there is a small one (on top in the middle) that goes to the charcoal canister up front but it won't have any affect on filling the tank...

I have noticed my 97 wants to be a little slow on really hot days, I usually go slow until I have about a gallon in it, then I can go to full speed... I think it sort of cools the tank and reduced the vapors a little.

 

Well there are multiple vent lines on each tank, the small ones just go to the charcoal canister. Generally each tank will have a large vent tube, and it will usually run up along side the filler hose, and then join into the filler neck assembly.

But it looks like this generation of F-series has the vent tube concentric inside the fill tube, so you will probably need drop the tank and remove the entire filler neck to see what's going on.

 

I check it out a little later ... I'm gonna try to blow thru it and see if it flows easily. I get my "Government crumbs" (social security check) tomorrow, so I will try to fill it at a different station, to make sure it wasn't the nozzle screwing up !!!.. this week we are running around $3.14/$3.24 per gal. ... last week it was $2.98 to $3.09 ... IT FIGURES !!!! Dave !!!

 

Subscribing to this. I had the same problem last Sunday. The pump kept shutting off when I was trying to fill the rear tank. Front tank filled fine with the same pump.

 

Vent pipe is AFU. Had one do the same thing after I mashed the pipe shut after a fuel pump changeout.

 

I can see that happening BUT, I didn't do anything to the pumps or tanks ... ever. So I am about to go out there and crawl under to see what I can see and report back later.. I really don't want to have to pull the front tank. I think I have another fill tube for the front tank someplace ... if not I have access to a 92 F 250 for parts MMMM !!! Dave

 

I found a "vent line" near the front tank it had a kinda of a plug in the end to keep dust and water out. I got it down and blew thru it ... clear ... no problem. Tomorrow when I fill up I'll check it out ... the canister is ok because the rear tank works well ... so we'll see !!! Thanks for the guidance !!!! Dave

 

I know there was a recall for the front tank overflowing with gas from rear tank in the early-mid 90s. Not sure if that is what it is. Good luck fixing the problem.

 

Thanks, but I'm fairly sure that's not my issue because it only happens when I gas up !!! as I understand it was the rear tank overflowing the full front tank !!! Thanks for the input take care ... Dave !!!

 

Well, something is pushing fuel back out, so there's a blockage somewhere. You sure the gauge ain't reading wrong and showing empty when you actually got a full tank? Perhaps your rear pump filled the front tank.
Mine seems to transfer both ways when running with less than 1/4 tanks.

 

Got it !!! blew out the vent hose under the truck ...both tanka worked just fine ...I think the problem was the nozzle at the station !!!

 

i hade same problem just filled er slow next itme it worked but the po had it sittin for 3-4 months prior to my purchase and fill up