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Fresh Water Tank Leak

Discussion in 'Technical Discussion' started by JWY, Jan 28, 2021.

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  1. cleanslate

    cleanslate Senior Member

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    May 29, 2018
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    Location:
    Cherry Hill, NJ
    If you can get the tank out a stainless kitchen equipment fabricator/Hood builder could weld on a new bottom. Just make a pan 16ga. S/S 304 grade is ok, but 316 would be better, to fit the bottom and come up all sides a few inches and weld it around.
    Perhaps it can be lifted and welded in place on the boat. Yes, TIG welding or Heliarc welding would be they way to go. It may only need that , clean up the spot hammer it shut at feed the gap with a thick TIG stainless rod in place on the boat. You can use those brazing / welding pads that good AC/Refrigeration mechanics use to aid with protecting the boat from heat/damage. And/or a welding blanket.

    But if it can not come out I would drain the tank, let it dry . Try to lift the tank at the bad corner if you can even an inch will help, sand it down and seal it with marine tex or 5200 .
  2. gr8trn

    gr8trn Senior Member

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    Location:
    Portland, OR
    Heck for a three year seep in one corner of fresh water tank, I would go with silicone Rescue Tape first.
  3. cleanslate

    cleanslate Senior Member

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    Perhaps try that stuff from old swifty ..Frank Swift and Flex Seal! Ya never know . I would go with the paste version . But then again the liquid version might be better. Hmmm.
  4. Brian G

    Brian G Member

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    Location:
    Nashville, TN
    Just a word to the wise about TIG welding. I had a local engineering firm fabricate a swim ladder for me and when they installed it under the swim platform, they screwed about 10 lag bolts right into what turned out to be a portion of the aft fuel tank. To fix the screw holes, they had to cut a hole in the top of the swim platform and then through the top of the tank to weld the holes shut from the inside. Apparently, they didn't disconnect the grounding wires and straps in the engine room so the TIG welder sent a jolt of electricity throughout the boat which blew out a number of voltmeters in the power panels. Needless to say, it was a major hassle. I had to hire another company to oversee the repair in order to get it done right. It took months!
  5. cleanslate

    cleanslate Senior Member

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    Location:
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    Oh wow! That's awful! Yes that sure could happen. Never though of it, the grounding issue. The lag bolt issue on the other hand...ALWAYS measure first before you drill through the hull.

    Find the closest existing penetration through the hull and measure from that to get an idea where you are then drill through the hull with a 1/8'' or so pilot bit and see where you really land. Then you can see if you have the'' all clear'' to go ahead with the installation. Also any transom platform should be through bolted, not screwed or lag bolted in.