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How do I remove a stuck 1 1/2\" square head plug?

Oilman7018 Member Posts: 1
I was reading and I understand the whole part of heating the plug up and have done it before. I just dont understand what part the water plays


  • Daniel_3
    Daniel_3 Member Posts: 543

    This thing is quite frozen on the 2" steam main. Should I buy some kroil or something? I tried heating the fitting but only proceeded to mar the square head badly. Why didn't they use a hex head instead. . . .
  • No easy way

    that I know of Daniel. Just brute-force and perseverance! Perhaps you didn`t heat the fitting enough? You may wind-up loosening the side you didn`t want-to in the first place. Heat the fitting, not the plug itself.
    Good Luck!

  • ALH_4
    ALH_4 Member Posts: 1,790

    Maybe one of these?
  • bob young
    bob young Member Posts: 2,177

    slice it out . solid = drill it. hollow = no drill [easier] good luck. a bit of work but do-able if you want it out . if you heat that baby up cherry red, it should unscrew.
  • Daniel_3
    Daniel_3 Member Posts: 543

    It's probably hollow as it looks a lot newer than the early 1900's. All the piping was probably redone at some point in the last 50-60 years.
  • Daniel_3
    Daniel_3 Member Posts: 543

    I'm too cheap to buy those for this job =)
  • Daniel_3
    Daniel_3 Member Posts: 543

    All I have is a benzo auto torch which probably won't heat it up enough.
  • Eric Johnson
    Eric Johnson Member Posts: 174

    The few times I've done that, I've found it works best to start the radial cuts out with the Sawzall, but finish them off with a hand-held hacksaw blade. You can feel when you hit the threads on the fitting when you do it by hand, and thus avoid cutting into them. Then just cold chisel out the sections.

    Stick an easy-out in the hole and maybe avoid the radial cutting altogether, though I doubt it.
  • jim lockard
    jim lockard Member Posts: 1,059
    you may find

    that is the cheapest way,or burn it red and put the pipe wrench to it.
  • Joe_75
    Joe_75 Member Posts: 57

    I have never seen one not come with the right heat. The trick is that you don't want to heat the plug. I have seen guys heat them and then spray corrosion X one them, but you may burn the house down if it gets away from you.
  • Pete_31
    Pete_31 Member Posts: 26
    Frozen Plugs

    An old fitter showed me this once. We were removing 1" plugs from an old vac steam system. Had to remove like 200 of them. First heat plug with oxy acet setup till plug gets red then carefully pour water on plug only about a cups worth. Then remove with proper sized combo wrench or socket. This was after attempts at heating casting around plug. Also tried penetrants but nothing worked till we tried this guys trick. Like I said we were retrofitting convectors to install an air vent.
  • I use the same method as Pete

    except I use an ice cube on the plug and only my regular air acet. torch. Bob Gagnon

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  • ttekushan_3
    ttekushan_3 Member Posts: 958
    Pipe wrench might be the problem.

    I always seem to destroy the square with a pipe wrench. A large monkey wrench or large sturdy crescent has always worked better for me.

    Love the water or ice cube idea tho. Gotta try it.

  • Daniel_3
    Daniel_3 Member Posts: 543

    What a knowledge base here on the Wall . . I'm amazed!
  • Daniel_3
    Daniel_3 Member Posts: 543

    I'll try the crescent Terri, thanks. I'll try the ice cube and water trick as well. We'll see what happens =)
  • Scram Bulleggs
    Scram Bulleggs Member Posts: 12

    I always called it "cold shocking" Have had to do it to many times. Get the fitting red hot then dump ice ice cold water on it. Something to do with the fast expansion-contraction cracks and seperates the rust. Always loved doing it around someone who has never seen it. They are always surprised.
  • bob young
    bob young Member Posts: 2,177
    hot--cold shock

    It could crack a cast iron fitting or radiator.
  • Daniel_3
    Daniel_3 Member Posts: 543

    Hopefully it just loosens the rust when I do it. Since I don't have the acetyl torch will a benzo blue can work good enough Bob?
  • Mark Hunt
    Mark Hunt Member Posts: 4,909
    One other thing to try

    If you can still get a wrench on it, try smacking the wrench with a lump hammer.

    "Shock and awe" if you will. That sudden SMACK tends to loosen things up.

    Mark H

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  • Daniel_3
    Daniel_3 Member Posts: 543

    That was the first tactic Mark, with a 24" pipe wrench which prceeded to crumble the edges of the head. I could try it on a crescent wrench with a rubber mallet after the heating up and cooling off.
  • tim_38
    tim_38 Member Posts: 2
    2\" plug

    cut the square of with a sawsall that will leave a hole in the center then cut a pie stile cut down to the thread and tap it out with a chisel
  • William Faust
    William Faust Member Posts: 168
    I have the same problem

    with a stuck 2" skim plug. I bought precisely that Snap-On Tools Co. socket that is shown in your post's link. I didn't want to buy a 3/4" ratchet, so I bought a 3/4" x 1/2" reducer to get down to 1/2" drive. Even with a length of pipe over my ratchet, I still can't move the plug. I bought a can of aerosol Kroil and I sure hope that that works. I'm really beside myself because I'm pretty sure that the contractor who installed our home's boiler (for a prior owner) never skimmed it.

    Having gone back to the Snap-On Tools site, I now realize that I should instead be using a 1/2" drive breaker bar rather than a ratchet. Damn, those things cost real money. Gonna have to find one to borrow.
  • not sure if the benzo will work

    I forgot about smacking it. I tap it pretty hard with a regular hammer when it hot. I think the heat expands the outer fitting and the cold shrinks the plug or male thread. I have never had 1 break. Bob Gagnon

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