I bought my 2003 F350 long bed in 2020. On and off, I have smelled fuel vapor coming from the gas tank area. I finally got around to buying one of those mini-smoke machines to track the source of the leak. The vapor leak is from one of the fuel vapor vent fittings on top of the gas tank. My tank is the 38 gallon size and is a long, rectangular shape. The tank has two of these fuel vapor vent fittings, one near the front of the tank and one near the rear. On this tank, those vent fittings are not the type that twist out. The fitting is molded into the tank somehow.

I searched and found a few threads on this problem, but the threads are older. Some have tried JB Weld to seal around the fitting. Some have tried plastic welding.

I just wanted to check to see if anybody has had any luck with a solution to this problem.

My truck has not yet produced any codes related to the EVAP system, but I imagine that could happen if the vapor leak gets any worse. I am trying to be prepared with an action plan in the event that I get a code related to this issue. In Arizona, I won't be able to keep the truck registered until I clear all codes.

Below is a link to the fitting that I am talking about. This fitting will work with a tank that has the twist-out style of fitting. Apparently, the 2003 tank does not have the twist-out fitting, even though Amazon indicates that this fitting will work for my tank.

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Screengrab for future generations for after the link expires:

 

Can you post a picture of yours?

Does it twist at all?

 

Interesting, I have been noticing a fuel smell lately coming from the gas tank area. I might have to find my smoke machine setup. How did you see up there with the bed in place? I have a borescope and it is still sort of difficult to orient myself.

 

fits select , meaning tanks with twist out valves , safe ways to fix molded on are small , can't use heat

 

If you slide under the truck from the driver side feet first in line with the fuel port, you have plenty of room to lift your head up between the frame rail and sheet metal of the truck's body. From this position with a decent light, you can see the top of the tank easily and clearly. With the smoker going, I could see the wisps coming out from the fuel vapor vent fitting that is on the front of the gas tank.

 

So what are the safe ways to fix molded on? I don't understand from your post what you are suggesting.

 

Take a look at this thread for a picture of the v10 composite gas tank and the fittings that I am talking about. The thread also explains that the fitting does not twist off.

​​​​​​https://www.ford-trucks.com/forums/1...to-remove.html

 

Ah, yes, now I get it.

If the leak is a crack somewhere there and the fitting works properly otherwise, I'd just epoxy the leak and a little bit around the leak.

 

This just happened to me. A squirrel or something had chewed through the male fitting. I cut the fitting off, pushed a piece of plastic barb that came with a vacuum line kit that I got on amazon. I plastic JB welded it in place and then used a new piece of hose onto that. Easy peasy. You are correct, on these 38 gallon tanks, those fittings are not replaceable. It's annoying for sure.

 

safe fix is a new gas tank , real world , can't plastic weld it for fear of a explosion or fire, might seal with something like marine tex might not,

 

other reasons for my view on auto repairs, which are always about making a proper, not a rube goldberg make it work repair .which when it comes to gas will never move from a totally safe only repair

50 plus years dealership background C,B A tech, shop Foreman
ase master and factory trained and certified master tech,
dealer service adviser
dealer service manager ,
manufacture district service manager
EMT on a local ems squad of which yes i have seen to many people with burns from miss handling gas and or other flammable fluids

 

My first thought was a new gas tank. After spending some time researching, I can't find any replacement gas tanks. I guess not enough of these gas trucks with the 38 gallon tank were sold to keep the replacement tanks in production. I can find plenty of steel tanks for the diesel models, but no luck finding a new tank for the gas engine trucks. That is why I am looking for other solutions.

 

They might still make an oversized tank for it.