fuel tank leaking

[Posm]

I went to fuel up this morning at a station with a decided tilt to the drivers side and filled it up to the rim like I always do and then went in to pay. When I came out there was fuel running out from under my truck near the filler neck. I looked under and could see a study drip from the center of the tank running from the top side. After the tank got down 5 gallons it quit dripping. I probably did not loose a pint all together but it still bothers me. I suspect the leak is at the one of the "holes" in the top of the tank. IE the draw off, the sending unit, or the filler neck. Any help you may offer would be greatly appreciated!!!

 

[illflem]

Check that the hose clamps on the fill and vent hoses are tight.

 

[B.G. Smith]

Leak

The sending unit/fuel pickup/ fuel return assy. is held in the top of the tank by a large plastic nut with knobs on it. Mine leaked there when I filled it all the way to the top of the nozzle. I got under the truck and sat up between the drive shaft and the right frame rail and you can get a good view of the nut. I used a long wood hammer handle (sledge handle) and a rubber mallet and tightened the nut, no more leaks. bg

 

[Kalaehina]

My tank also leaks at topped off level, but continues to leak for the first 50 miles or so, not really sure how many gallons that equates to. When I changed my sending unit and had the tank out I noticed a trail coming from the area where those strap looking handles are on the top towards the front of the tank. I could never pin point it. I'm sure this is not what's happening to you but thought I'd share it. It drove me to just get a new tank. Good luck

 

[GSchlegel]

Reminds me of a story kinda related to this story. I stopped at a truck stop in Missouri. I was fueling up when a guy pulled and started fueling his new CTD. Fuel just poured on the ground. He said he just came from the stealer. They worked on the fuel tank and forgot to hook up the filler hose to the tank. I'm glad diesel isn't volatile cause this guy was HOT !



Gene

 

[Posm]

Worst than I thought!!!

I finally got the time to crawl under and check out the leak. I found one of the small lines that goes into the tank was broken. The line goes down the right frame rail and across a cross member and then into the tank. The line goes from metal into a plastic elbo and then a rubber line into the tank. The plastic elbo is broken and the rubber line is gone. I guess the fuel leaks back through the tank outlet, but only when the tank is full. I see a lot of grime on the top. Does any body know what this line is for? I would guess that it is either emisions or a breather line. I think the fuel return line comes down the left frame rail.

 

[WestTN]

fuel tank leak

When you fill up to the cap you are filling the expansion area. The tank will leak at the top when there is no where else to go. If it didn't, the tank could crack when the pressure builds.

 

[baby.driver]

I found that if I left the aux. fuel tank valve open while parked the fuel leaks out the pressure relief valve on the top of the main tank.



Jay

 

[Cummins Corvette]

Re: fuel tank leak

Originally posted by WestTN

When you fill up to the cap you are filling the expansion area. The tank will leak at the top when there is no where else to go. If it didn't, the tank could crack when the pressure builds.

I always fill mine up to the top and I have never had any problem.