Stripped water fitting

[Eric]

Well pulled the water tanks out to clean them and unknowingly ripped a bottom most plug out of the tank... I've tried ever typical method ... Re tapping it, plumbing cement ... I even tried threading it with a bigger fitting... All leaking. Any suggestions? 100 gallon tank I'd had to just waste!! 

[bottomacher]

What is it made of?

[Iceni John]

Is it a polyethylene tank?   They often have their fittings spin-welded in, because it's very difficult to glue them.   I've heard that there is a glue that will work, but I've never seen it.   I think your only practical choices are spin-welding (by someone with the correct adapters and fittings), plastic welding (using the appropriate filler rods), or using good bulkhead fittings (but they'll need smooth surfaces to seal against).   Maybe a roto-molding company can help you?

John

[Lin]

I suppose, if all else fails, you could open an access hole in the top of the tank, and get a new fitting that could be held in place by a nut that you could attach through the new access hole.  Sealing the top hole should not be much of an issue.  Of course, as mentioned, someone with the right equipment and materials could handle it better.

[Cary and Don]

We had a small hole.  Tried everything short of taking it to somebody to fix it.  Finally tried a big fiberglass patch.  Not leaking.  Our tanks are in plywood boxes, so they are supported for the water movement.  It really stuck tight. A fitting might be a problem though.

Don and Cary
1973 05 Eagle
GM 4107
Neoplan AN340

[fraser8]

I fought a leaky valve in my old motor home for far to long, I finally took the thing out and had it spin welded on. I used every type of glue and epoxy I could find, after buying all the different ones it was cheaper to just have it done properly. That poly is a female dog to try and fix with home remedies.

[robertglines1]

Easy way to do this is a large fitting you can bolt thru from both sides.  The hole has to be large enough to get the bolts and flanges thru but then you can adapt them down to the size you need.  You basically sandwich the tank between the new flange with a gasket on one side.  Beats the cost of a new tank.  Plus if you don't need- the outlet makes a large clean out for future use.

[Larry B]

  I use to weld plastics from time to time. It is done with hot air been blown though a small hole (1/4"). There is usually not much that will stick to plastics except the same type of plastic. If you have the tank out it would not likely cost much to have it done. You have done the hard part. Getting access to weld needed. The large bolt through patch should work. If patch is on bottom you will need to modify tank supports
  Larry B   

[chev49]

bolt thru hole, or plastic welding.. if you dont know type, a burn test would tell you.. i think the last one i fixed, instead of welding it, i epoxied a fitting to it.   normally i weld plastic tanks, and car plastic after determining which plastic it is.. the harbor freight plastic welders  should work ok if everything is prepared right... just my experience.

[Eric]

Well I'll figure it out tomorrow with all your ideas it is a poly tank and it's the main filler :/


Thanks
Eric