pin hole leak speedster fuel tank

[Abender]

have a leak in the top of right wing tank. looking for ideas for sealing it up without cutting into the fabric

[N213RV]

Pictures might be helpful. I had a pinhole leak on the bottom of my finished wings. I was able to locate the leak and I installed an inspection panel directly under the repair area. I used a boroscope to precisely locate the leak and put a fiberglass patch over the pinhole.

[Av8r3400]

Different sloshing compounds have been used with varying degrees of success/failure. At the very least you will be removing the wing to slosh whatever compound(s) you choose inside the tank.


Imo, you do not have a good prognosis. The only sure way to permanently fix a leaking tank is to remove it and probably replace it. Once they start to leak, this means some type of erosion has happened starting the leak and it will only continue.

[avidflyer]

I would try caswells or KBS coatings tank sealer first of all. If it doesn't work, you are out about $40 and the work of doing it. If it does work, you saved a bunch more work replacing the tank, not to mention the cost of the tank. JImChuk

[HighWing]

For what it's worth. On one of the Idaho trips - as I recall about 2004 - I noticed about a half dozen small "pimple" like bubbles in the Aerothane on top of the wing just inboard of the fuel filler neck. Uncertain as to their cause, I finally took a razor blade and cut one off. It was filled with fuel. Apparently I had several pin point leaks on the top of the tank. The timing was consistent with California outlawing the MTBE additive and substituting Ethanol. Cause and effect - pretty suspicious. I re-sloshed with the oft maligned Kreem - after removing the factory Kreem with Acetone. For the next three years using California's 10% ethanol reformulated fuel, except on cross country trips, I had no problems with leak issues. The airplane was destroyed in our not so perfect emergency landing near our home ten minutes into our flight to the 2007 factory Fly-in - explanation for the short only three year history.

Pics of the wing support I made to enable wing removal and sloshing with minimal effort. The attachment of the wing tip to the support was a fully mobile gimbal for unlimited movement and the inboard support folded out of the way for manipulation of the wing.

[Abender]

For what it's worth. On one of the Idaho trips - as I recall about 2004 - I noticed about a half dozen small "pimple" like bubbles in the Aerothane on top of the wing just inboard of the fuel filler neck. Uncertain as to their cause, I finally took a razor blade and cut one off. It was filled with fuel. Apparently I had several pin point leaks on the top of the tank. The timing was consistent with California outlawing the MTBE additive and substituting Ethanol. Cause and effect - pretty suspicious. I re-sloshed with the oft maligned Kreem - after removing the factory Kreem with Acetone. For the next three years using California's 10% ethanol reformulated fuel, except on cross country trips, I had no problems with leak issues. The airplane was destroyed in our not so perfect emergency landing near our home ten minutes into our flight to the 2007 factory Fly-in - explanation for the short only three year history.

Pics of the wing support I made to enable wing removal and sloshing with minimal effort. The attachment of the wing tip to the support was a fully mobile gimbal for unlimited movement and the inboard support folded out of the way for manipulation of the wing.
Great idea for the wing removal for sloshing. Thanks for the input

[Abender]

I would try caswells or KBS coatings tank sealer first of all. If it doesn't work, you are out about $40 and the work of doing it. If it does work, you saved a bunch more work replacing the tank, not to mention the cost of the tank. JImChuk

Thanks Which of the 2 preferred?

[Abender]

Different sloshing compounds have been used with varying degrees of success/failure. At the very least you will be removing the wing to slosh whatever compound(s) you choose inside the tank.


Imo, you do not have a good prognosis. The only sure way to permanently fix a leaking tank is to remove it and probably replace it. Once they start to leak, this means some type of erosion has happened starting the leak and it will only continue.

Thanks for the input

[avidflyer]

I used KBS coatings once. It was on aluminum tanks in an Avid. They eventually started to leak again, but it did fix it for a while. Aluminum tanks were a poor choice for the Avid and Kitfox wings, as they tend to bend and twist somewhat in flight, leading to cracks in the aluminum tanks. That's why both companies went to fiberglass tanks after a while. I've heard good things about Caswells. I guess I would go with either one. JImChuk

[HighWing]

Thanks Which of the 2 preferred?

The pictures are the two ends of the same support. With the inboard end extended up, the bolts attaching the wing and the lift strut can be removed and the wing can then be rolled away from the airplane by one person. Then after folding the inboard support down, the wing can be rotated and lifted up and down to slosh. A step stool or other platform needs to be used to lift the inboard end high enough to slosh all internal surfaces of the tank. I found that having a second person to help hold the inboard end made the actual sloshing much easier.