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Leaking radiator question

zoom Member Posts: 72
This is for a two pipe steam system running at 6-8 oz.

Work was being done in the house and it seems that someone collided with a radiator. As a result, there is now a small leak where the trap tail peace enters the radiator. When the system is under pressure the radiator hisses air and leaks some water. There is no visible damage.

Aside from from cutting out the old trap tail piece and replacing it, is there any less drastic way to seal this small leak that can be tried first?

Any help is much appreciated.


  • Sailah
    Sailah Member Posts: 826
    Is the tailpiece damaged or split? You could remove trap and try burying tailpiece a little further or remove and redope. Where is the leak? At the NPT threads going into radiator or at the trap union?

    From the sounds of it the tailpiece is cracked at threads. Personally I'd remove and replace trap seems like the best long term solution, although I have had various luck with magic goop compounds. Often the labor spent to prep the material to getting a good bond far exceeds the part cost for a new trap. I reserve magic goop (Loctite Metal Master 98853 is my personal favorite) for parts where they are just not replaceable or the removal would be a massive task. Usually I die grind the surrounding material and prep with acetone to ensure a good bond.
    Peter Owens
  • MilanD
    MilanD Member Posts: 1,159
    You can try 2-part epoxy putty into and around the crack, and then wrap it with some self-sealing repair tape, and finishing it off with a few or 3 clamps. Make sure surface is as clean as you can get it, and of course, work on it with the system turned off.
  • zoom
    zoom Member Posts: 72
    Thanks for the ideas. The leak is at threads that go into the radiator itself. The radiator is old and the tail piece will certainly have to be cut out if a quick fix doesn't work. That could damage the radiator further, so I will try a quick fix first.
  • Big Ed_4
    Big Ed_4 Member Posts: 1,775
    edited March 2018
    You can try epoxy first ... Cracked radiator at threads , right ? I would give it a try ... You may want to drill a hole at the end of the crack so it will not travel...
    I have enough experience to know , that I dont know it all
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,510
    Just remember that this patch will only be a temporary fix, and that a permanent and proper repair would be the replacement of the trap and spud.
    Later on, in the dead of some future winter, when it drips again, you will regret the improper solution.—NBC
    New England SteamWorks