Forum Discussion
Mike_M2
Aug 22, 2013Explorer
I had a crack in my black water tank a few months back and found a permanent solution. Use M5200(it comes in black or white) and spread it all over the crack, then place a piece of hard plastic over that. The cure time is very long for this product, but it is permanent. I've used it to seal holes on boats under the water line! Carefull tho, once applied there's no getting it off again. Big advantage over JB weld is it stays flexable whereas JBW does not.
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