For years there has been a fuel smell when the tank is full/ near full. I dropped the tank today to replace the fuel pump and found these visual gems.

You can see that it's been leaking at the connector along time. And it's leaked bad enough that there's liquid marks down the tank. The back doesn't look so good either.

Does anyone have thoughts on why this is so bad and what's the right way to fix it?

 

So I'm on a rain delay after getting the pump removed and replaced. I've done some Google searching and it seems to be a common problem that the vent fitting cracks on these tanks. Not big cracks, but enough to leak.
I ran to Autozone and picked up some plastic tank repair. I'm gonna clean up both vents and coat any imperfections I see in hopes of fixing the leak.

 

I got the vents cleaned and found a good sized crack on each one in the same place. There crack was every bit 1/16" wide x1/4" long. I took a picture of the front one.

With the flash, crack under the port.


Without the flash, crack under the port.
It was starting to rain again, so I didn't get a pic of the fix, but I put the sealant completely around the port tube and about halfway around the whole vent housing.
This is a pretty major design flaw and safety issue considering it's the gas tank.

 

Are you confident this will hold up under vibration?

 

No. This was the only plastic gas tank repair they had, so I went with it. I plan on this truck being around/in the family for many more years, so time will tell.

 

Ii sounds like it's good for a temporary fix which gives you time to save up and plan to an R&R replacement with a new one, just so you don't end up stuck somewhere at an inconvenient moment.

 

Really odd for them to crack like that. Maybe some previous owner tried to pry them out without unlocking them first? You unlock 'em with a quarter turn counterclockwise, then they just pop out. One of the other available Ford parts might fit, with the difference being just the hose fitting orientation. You'd just have to pull it out and compare. But Ford used the same size hole for many years, on many models. Like one from an F150 might be easier to find. Even in a junkyard.

 

Considering the asymmetry of the fitting, I'm sure there was a mold seam right were the crack is during production, so I'm not surprised to see both of mine cracked along with multiple reports of similar leaks on the internet. Knowing we bought the truck 1.5 year used in 2004 with 30k miles on it, I'm pretty sure the first owner didn't touch them. Also, they look to be "welded" in place because the black tank plastic and the off-white fitting plastic is melted at the seam, look closely at the pictures. I don't think they're meant to be serviceable.

 

Yeah, you're right. They do look welded in place. Well, that sucks 'cause the tanks aren't available anymore. If the plastic epoxy doesn't work out maybe plastic "welding" will be in order. The Explorers are still replaceable. Strange idea Ford had here.

 

It only takes one little air bubble to get in there during the injection process to cause a weak spot.

 

We're short of 2 years later and the front is definitely leaking again. I wish the ports were serviceable or the whole tank still available.