I have to repair a puncture in my Escape's water tank and I ran across a suggestion on a RV forum of using hot glue. The reasoning was that he tank is polyethelene, and the glue sticks are also poly, so they stuck well together. The post also suggested, I believe, flame polishing the torn edge with a small butane torch. I guess that melts the edge a little and provides a smoother attachment point. I did not make notes or links because this wasn't a problem I had at the time I read the post!
Anyone tried this? The 10 gallon tank I took out of the U-haul
also appeared to be patched at least two different ways. One way did look like it was done with a hot glue gun. The other method looked like it involved RTV and some kind of (maybe) rubber patch.
If I had the clearance I could just drill and tap it and install a plug, but the plumbing that actually created the hole is too close by to pull that off easily.