My hydrapak bladder sprung a leak a month ago, during the Karapoti Classic MTB race, and I have not used it since. It’s time to fix it or buy a new one. Has anyone tried fixing leaky camelbak bladders? It’s got about a 1cm split at the seam along the bottom. Would superglue do the trick? Can I melt it back together with an iron? Or is there some other means of sticking it back together?
Superglue will not work for this application. You need to weld, or remelt, the seam. Hot air welding works best on polyethyelene or polypropylene (the bladder material) because nothing sticks to the welded surfaces afterward but it requires specialized equipment.
I would recommend a tiny flame torch. Try to get the surfaces just hot enough to melt without igniting. If they ignite it won’t hurt anything it is just difficult to control the melting.
The drip technique is unlikely to work for a water bladder. The drip technique uses a plastic stick of similar material. Ignite it with a match and let the melted droplets drip onto the seam. If it were a hole in the side, this technique would probably work. On a seam you’re trying to melt too much material and the resulting joint would be cold and weak.
You can try bonding the seam using heat. Take a butterknife/paint scraper/other flat metal object, heat it with a lighter, and then use the implement to sort of iron in a new seam.
I wouldn’t want to apply flame directly to the bladder, since burning plastics emit all sorts of noxious chemicals (like chlorine gas, yum!).