Forum Discussion

Nutinelse2do's avatar
Nutinelse2do
Explorer
Jan 15, 2016

Black Tank Leak

Not a crack, just weeping when the tank gets almost full. Found the spot.... It's the tank its self, not a fitting. Again... not a crack, and not the fittings.

What do we use to repair it?... Tried ABS Glue, which did nothing. Read on Bondic, and Flex Seal, which both get pretty crappy reviews.

What would be the best option to fix it? Fiberglass welding, glass cloth and 3m sealant, plastic tank repair kit?

Please let us know if something has worked for you. We really don't want to replace the tank.

Thanks for your time
Seeking Advice
  • rjsurfer's avatar
    rjsurfer
    Explorer
    Jan 17, 2016
    Plasti Mend worked great on my black tank, had crack in same spot. Make sure you do multiple coats and don't be afraid to spread it at least a few inches around crack.

    In a pinch you can make your own, scrape tiny pieces of ABS into a glass then add some ABS thinner or Acetone to make a slurry.

    Ron W.
  • Nutinelse2do's avatar
    Nutinelse2do
    Explorer
    Jan 15, 2016
    Thanks for the clarification on the tanks Byron. That's what our research showed too. Looking forward to getting it ( Plasti-mend ). Seems it will be the correct fix.

    Thanks again!
  • 12thgenusa's avatar
    12thgenusa
    Explorer
    Jan 15, 2016
    Plastic welding works very well on ABS and is not expensive. I have had two different repairs made on an ABS galley tank with excellent results, approximately $30 each.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jan 15, 2016
    Plasti-Mend works very well on ABS

    Black Waste tanks are ABS

    Milky White or light Grey Fresh or Waste water tanks are polyethylene
  • golf_bears's avatar
    golf_bears
    Explorer
    Jan 15, 2016
    I accidently drilled a hole in the bottom of my grey tank about a year ago. I got some JB Water Weld from Home Depot. It's a two part putty material that you "knead" until the color changes. I applied it while the tank was still dripping. Once it set the leak stopped and hasn't leaked since then. Worth a try. I think it cost less than $5.00.
  • Nutinelse2do's avatar
    Nutinelse2do
    Explorer
    Jan 15, 2016
    Hi.
    Think its ABS. Ordered a Plasti- mend black tank repair kit.

    It's about $50 with shipping, but supposedly it works.
    Could not find any negative reviews on it, and has a 1 year guarantee.

    Will report back after we try it next month.

    Thanks all
    Safe travels
  • nomad_297's avatar
    nomad_297
    Explorer
    Jan 15, 2016
    There is no approved sealant for polyethylene, if that is what your tank is made of.

    Bruce

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