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Removing plug from ancient radiator.

Gasper Member Posts: 148
Does anyone have any tips for removing a 1-1/2" hex plug from a 85 year's-plus cast iron radiator. I do not need the plug.


  • the_donut
    the_donut Member Posts: 374
    Disconnect radiator. Scrape back paint. Soak in penetrant oil. Let sit overnight. Clean off and heat with torch. Find socket that fits perfectly and breaker bar that is long enough. Set radiator on side so that torque is in direction of floor. Use constant force, don’t jerk, or you may round off plug. If still stubborn heat plug again and cool. Repeat.

    If it still doesn’t come, and is brass, cut end off, inside is usually hollow. Small enough blade should fit in hole to cut pie shape sections out. After two quarter moon section are gone, use chisel and hammer in direction to loosen plug.

    If steel, drill out hole large enough for blade and do the same as brass. Before careful not to nick threads.
  • Gasper
    Gasper Member Posts: 148
    Does it make sense to mostly heat the radiator right around the plug, to expand the radiator, and not the plug?
  • adasilva
    adasilva Member Posts: 144
    Any heating in the general area will cause it to expand and contract breaking it free.
  • gerry gill
    gerry gill Member Posts: 3,010
    we use electric impact wrench
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • Gasper
    Gasper Member Posts: 148
    Makes great sense. Thanks gentlemen.