Forum Discussion

torinoscj429's avatar
torinoscj429
Explorer
Feb 09, 2014

Leaking FIBERGLASS Black tank

Hello all

My Class B rig, a 99 Xplorer XLWT, has a leak in the black water tank, which is fiberglass, and resides INSIDE the vehicle, and is molded into the shower enclosure. Removal of this tank is pretty much impossible without tearing the whole rig apart.

I can't see the leak, but the carpet inside is wet, and eventually, the moisture makes its way outside...that's how I discovered the leak. (Edit: Runs in the side of the tank are resin from initial manufacture.)

Is there some sort of material that can go INSIDE the tank to seal it? I think I can manage to get the toilet off the tank to get in there and clean it well enough.

Not fun.

Ideas?

Thanks,

Gerard

17 Replies

  • Almot's avatar
    Almot
    Explorer III
    repairing a fiberglass is a trifle - as noted, use epoxy and fiberglass fabric (fabric has better adhesion than mat, too long to explain). You can't repair it if you can't access the leaky spot, obviously.
  • 352 wrote:
    The more I review the picture it looks like the water droplets come from mid tank or above.


    The runs in the photo are fiberglass resin from initial manufacture.

    I know it's the black tank, because I turned off all the other water, then put a gallon of water through the toilet to the black tank. The carpet got wet, and within 30 minutes, water was dripping outside.

    I can feel wet carpet under the tank, but it's impossible to access from the exterior.

    Gerard
  • 352's avatar
    352
    Explorer II
    The more I review the picture it looks like the water droplets come from mid tank or above.
  • 352's avatar
    352
    Explorer II
    How do you know it is the black tank leaking?
  • If it is indeed fiberglass and you can reach inside well enough to locate/clean/prep the leak spot, a mat-and-resin fiberglass patch should do the trick.

    You can buy such kits at any auto supply store for about twenty bucks.

    Side note:

    Are you sure it's leaking from the inside? I ask because that water in the pic is so clean I wondered if it could be condensation...
  • Maybe one of those plumbing pipe reliner companies can blow in their flexible liner that hardens. Its kinda like a balloon. You may have cut off and redo the outlet or something like that.

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