I found the product I meant – look into JB Weld WaterWeld.


I would probably use silicone but I’m definitely not an expert or anything.


It honestly depends on the pressure the water has on it in that area, but I used some flex seal spray on a crack in the gray tank exit pipe where it meets the valve assembly and it’s held firm since then, going on 6 or 7 months. Where your leak is located, it might be too much pressure but whatever you try, once you’ve located the leak, empty the tanks (mark the leak location) and get that area as dry as possible before applying anything.

Source: I assume that my black tank flush valve is what is leaking. What is the best way to fix? Initial thought was to just use epoxy (jb weld) around the valve.

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