Poly fuel tank repair

[sioux201 84]

 Anybody have any success repairing the old style Polly dash tanks?

[Allen Sutphin 705]

It all depends on where the leak it. And how big the crack or hole is. Sometimes easy to do and sometimes impossible.

[sioux201 84]

Allen

 After a Google search, found at Harbor freight part number 60662, Has a plastic welding kit, will post after trying it

[Allen Sutphin 705]

A friend of mine tried one of those on his challenger tank and he didn't have much luck with it. But the challenger tank might have been a different material and it was the one that uses hot air to melt the poly material. Hope it works for you.

[109jb 181]

Not a kitfox/avid tank, but I have many times repaired polyethylene gas tanks on snowmobiles and ATVs by plastic welding.  I do use the Harbor freight plastic welders that look like a soldering iron with a shoe type foot. I don't use those universal plastic weld sticks like come with the Harbor Freight plastic welders.   I generally look for something that has the same plastic symbol as what I'm plastic welding, which in the case of gas tanks is usually HDPE. I've used 5 gallon buckets cut into strips and also old gas cans cut into strips as filler. I plastic weld the crack without filler, then add filler as needed to come up past level giving it a good amount of filler in and over the crack. I have done at least 5 gas tanks this way and have never had one leak at or adjacent to a repair, and this is on off-trail snowmobiles and ATVs that are ridden rough and wind up upside down on every trip they go on. Be sure to flush the tank out first to get all the fuel out first.

[109jb 181]

Allen

 After a Google search, found at Harbor freight part number 60662, Has a plastic welding kit, will post after trying it

That is the one I use. As mentioned, don't use the universal sticks the kit comes with. They are rubbery and not the same material as the tanks. Tank should have a plastic symbol like attached if it is HPDE.  

[sioux201 84]

Thanks JB

 Great idea to use strips ( Cut like welding rods) from an old  polly Jerry can, HDPE

[ChrisBolkan 130]

Depending on the crack, you could end drill it so it doesn't spread and try some polysulfide aircraft fuel tank sealer. It is sticky, tough, flexible and impervious to fuel. You could even weld the tank and cover it with the sealer as insurance. It is amazing stuff.

[sioux201 84]

 82 and still learning, cut strips From a water jug and use the plastic welder ,to weld around the cracked fuel fitting, works great

[Buckchop 479]

I just had a crack in the top of my cowl tank right next to the filler neck so when u filled it up it wheeped gas.  Drained it and used a small hot iron for doing soldering on the crack, melted it back together to seal crack then for extra assurance i smeared some seal-all ontop.  
Thanks for the help with imfo on doing this little project!! now to get a better tank for a cowl/header tank that can still have the dash. 

[dholly 718]

I got an old KF3 panel tank for free if anyone needs it and wants to come pick it up, it's not really shipping-friendly. PM me