Hi, I am replacing the rear gas tank of my f250 with a new poly tank and have run into a situation, the original tank was removed years ago so I do not have it as a guide, but the side tank is still present but was recently vandalized, (idiot tried to siphon fuel but couldn't get locking cap out so he tried to cut filler hose and go in that way) He didn't make it. anyway since the line was cut I figured I would remove side tank and just use new poly rear tank. here's the confusion, the new tank has a roll over vent valve in the center of the tank for vent to charcoal canister, but the new filler hose does not have vent tube with it, should it? The side tank hose that was cut has a vent tube in the filler hose, (can see it where he cut it) so does the rear tank need both a vent valve in center of tank and a vent tube in the filler hose? Thanks for your help-JSP2242

 

You want both vent tubes - they serve two different purposes. The vent tube in the center of the top of the tank goes to the charcoal canister, which allows the tank to vent to atmosphere without taking in a lot of water vapor and also the charcoal canister collects fuel vapor to minimize the escape of fuel vapor to the air. The vent tube inside the filler neck allows air to come out of the tank when you are filling it. Without this tube, you will either have a situation where if you try to fill the tank, the gas pump will keep shutting off, or the filler neck will barf gas all over you while you are filling it.

 

You will need to get creative if he cut your interior vapor hose that goes inside the large fuel tube because this is not sold anywhere. You will either have to find one at a junkyard or find a suitable replacement hose. I was lucky enough to find a replacement hose that I made fit but it was not the stock style.

 

If the interior vapor hose only comes with the fuel filler tube (I couldn't find a pic of just the hose, and I cannot recall), I found over 150 of these midship tank filler tubes at dealers/obsolete parts vendors. One source has 114.

 

I could be wrong but I thought they didnt come with the fuel filler tube but I default to you as you are the master at these things.