Lower Fuel Tank Leaking

[brandanharmon]

I replaced the fuel pump and filter in the lower fuel tank and they work wonderfully. Happy about that. The bike starts and runs great....until I put fuel in the upper fuel tank.

The problem is that the seal between the metal top and the tank leaks fuel when the upper tank in filled. It seems that the feed from the upper to lower tank is simply gravity, but without a good seal the entire upper tank will drain through the leak. this is not a drip, but a constant soaking stream that seems to come from between the metal top and the black rubber gasket.

I have removed and replaced the pump sub assembly several times and have used both the original and the new black rubber gasket with the same results. I have checked the metal top for dents visually and with a machinist square and it seems flat and true. I am kind of running out of ideas.

Has anyone had this problem and found a solution?? How about gasket sealer?? I would appreciate any help from the collective.

Thanks

 

[v8-7]

See my response in your other post ..

 

[brandanharmon]

Thanks I appreciate your help on this.

I will take a look at the lip of the lower fuel tank and look for deformation. I have had the module in and out so may times I may have deformed it.

Brandan

 

[yosso]

Verify that you don't have any wires caught between the gasket and top cover...don't ask me how I know.

 

[brandanharmon]

Thanks guys I think you solved it!!.

The top lip of the lower fuel tank was slightly bent downward in one spot. I very gently bent it back up using a small Crescent wrench and a machinist square then put the sub assembly back in with the new gasket. I loaded a gallon of gas into the upper tank and everything looks dry! I will keep a gallon in overnight and check for leaks in the morning. If there is any seepage I will use a small amount of Permatex 2 but I am keeping my fingers crossed.

I am not sure how I bent the lip, but I put the assembly in and took it out 4 or 5 times and could have easily caught a wire or something between the gasket and the lid.

By the way for future guys, the depressions was very slight and I could not see it...I had to feel for it with my fingers.

 

[970mike]

Wow glad you found what the problem was, lets hope that does it now.

 

[Mick]

I am not sure how I bent the lip, but I put the assembly in and took it out 4 or 5 times and could have easily caught a wire or something between the gasket and the lid.

When you put the fuel pump assembly back in, did you tighten the nuts in the order specified in the service manual and did you use a torque wrench? There is a very specific order in which they have to be tightened. The order is different for the '03 compared to the rest.

See THIS post. There is a pdf "how-to" that I made when I replaced my lower tank that gives the page numbers in the manual ('03 & post '03) that show the sequence.

 

[brandanharmon]

Mick,

I didn't find your thread when I was doing the pump replacement. I wish I had seen it before; it is excellent.

I actually did follow the tightening sequence for my 2005. In retrospect, I almost certainly got a wire caught between the lid and the base of the tank and created a dent in the lower tank lip. Careful about the sequence, but screwed it up by not paying attention clearing the inner wires on the pump assembly.