Forum Discussion

Edsassets's avatar
Edsassets
Explorer
Mar 22, 2014

Crack in fresh water tank

I bought a new Dolphin 34' in 2004. To this date it has been a problem child. I'm getting it ready for a 6 week road trip and find the fresh water tank leaks. I believe it's a 75 gal. plastic tank and is leaking around the drain outlet.
My problem--I can't remove it. I can move it about 2 inches toward the opening but that's it. The tank is at the very rear of the coach on the drivers side. I'm hoping someone else has had this problem and can give me some advice. I believe it can be welded if I can get it out.As far as I can tell, I have to cut a hole in the bedroom floor to get to the top of the tank where I think the pick-up line is.
Can anyone help me?
Ed.
Class A
  • FIRE_UP's avatar
    FIRE_UP
    Explorer
    Mar 22, 2014
    Ed,
    If it is in fact PE or, polyethylene which, I'm assuming it is, then yes it's weld-able. The question is, can you get at the injured area(s)? If not, there are a number of newer, epoxy type glues out there that are pretty darn strong at binding to many surfaces. If you absolutely cannot get it welded, then this might be the way to go. You'd still need to get a dremmel in there to do some gouging where the cracks/breaks are so that the epoxy can get a good bite on things.

    These darn manufacturers don't make it easy to do things like this, even though there's a fair possibility that work on a water tank may be needed in the future.
    Scott
  • msmith1199's avatar
    msmith1199
    Explorer II
    Mar 22, 2014
    Are you sure there aren't removable panels to get to it? Although I've never had to take my tank out, I have noticed there appear to be panels that could be removed to slide it out.
  • BobandShaz's avatar
    BobandShaz
    Explorer
    Mar 22, 2014
    WOW that is ugly. Never thought about something like that

    You might check pet shops they have sealants for aquariums that might do the job

    GOOD LUCK
  • pianotuna's avatar
    pianotuna
    Nomad III
    Mar 22, 2014
    Hi,

    I repaired my water tank with a double patch of eternabond. You would need to be able to put lots of pressure on the stuff to make it stick. Place a small patch over the leak, then place a second larger patch over the first one.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 22, 2014
    National, you used to have to pull the Black and Gray to get the water tank out on some models. Yours may be this way. Doug
  • All58Parks's avatar
    All58Parks
    Explorer
    Mar 22, 2014
    pianotuna wrote:
    Hi,

    I repaired my water tank with a double patch of eternabond. You would need to be able to put lots of pressure on the stuff to make it stick. Place a small patch over the leak, then place a second larger patch over the first one.


    That's an interesting idea. There is no pressure to speak of, seems like this could work really well, especially as a short term, quick fix to get you through the next trip.
  • joraz's avatar
    joraz
    Explorer
    Mar 22, 2014
    Before trying to repair the tank, find out what material it's made of. I had a leaky black tank and tried the plastic welding route. That didn't work. That's when I found out about Cross Linked Polyethylene. (different molecular structure than polyethylene). If a tank is made of this material, it simply cannot be repaired. It can't be heat welded and nothing will stick to it. Anyhow, before doing anything I recommend you determine the material of your tank and then proceed accordingly. Good luck with this issue.
    jor
  • Gjac's avatar
    Gjac
    Explorer III
    Mar 23, 2014
    If you can't easily remove the tank but can reach the cracked fitting I would try an adhesive like Shoe Goo or Goop sold in Walmart and reinforce with gauze sheets. Drain and sand the area well clean with acetone. You want the acetone to attack the surface for a good bond. I assume the drain is under the tank so the excess solvent won't puddle. Apply about a .030 layer of adhesive then wet out the gauze sht and apply the wetted material to the .030 layer smoothing this with your fingers removing any entrapped air. If the crack is larger than .030 apply several layers. I have used this several times to fix cracks in plastic tanks.
  • 3sacrwd's avatar
    3sacrwd
    Explorer
    Mar 25, 2014
    I used JB Water Weld suggested by somone on this forum, and it worked well, easy to use, and hardened up perfectly.

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