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McGillicutty · 12-02-2013, 08:25 AM

Thanks for the responses guys (and gals?). So I got up the woods and dropped my coroplast bellypan and here's what I found. The Black and Grey tanks are really basically "pans" with a perimeter flange and a flat top glued (I assume) to the top. The flanges rest on a welded center cross member and an outer cross member that is bolted so it can be removed and thus the tank can be removed. I found that a section of the top had been separated from the pan/tank from the pressure of the water which actually did break the glued or welded seal between the top and the pan/tank. I was able to clean the two surfaces and lift the top enough to squeeze an ample amount of RTV into the joint, then I drilled a couple of holes in the tank flange and drove in two self tapping screws which pulled the top down to the tank flange tightly, squeezing out most of the RTV. I then applied more RTV to the edges of the joint and it appears to be fixed. I would have used ABS cement if I'd done this repair at home but I can always redo the repair with cement if the RTV doesn't hold long term which I'm not anticipating. What I don't understand is why the water didn't just come out of the vent? With the tank vent how did the pressure build to the point that it broke the tank? Anyway I doubt I will repeat this blunder and again, thanks for the responses.

12-02-2013, 08:25 AM	#33
McGillicutty Member Join Date: Jul 2013 Location: California Posts: 31	Thanks for the responses guys (and gals?). So I got up the woods and dropped my coroplast bellypan and here's what I found. The Black and Grey tanks are really basically "pans" with a perimeter flange and a flat top glued (I assume) to the top. The flanges rest on a welded center cross member and an outer cross member that is bolted so it can be removed and thus the tank can be removed. I found that a section of the top had been separated from the pan/tank from the pressure of the water which actually did break the glued or welded seal between the top and the pan/tank. I was able to clean the two surfaces and lift the top enough to squeeze an ample amount of RTV into the joint, then I drilled a couple of holes in the tank flange and drove in two self tapping screws which pulled the top down to the tank flange tightly, squeezing out most of the RTV. I then applied more RTV to the edges of the joint and it appears to be fixed. I would have used ABS cement if I'd done this repair at home but I can always redo the repair with cement if the RTV doesn't hold long term which I'm not anticipating. What I don't understand is why the water didn't just come out of the vent? With the tank vent how did the pressure build to the point that it broke the tank? Anyway I doubt I will repeat this blunder and again, thanks for the responses.