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Best way to tighten union?



  • SteamingatMohawk
    SteamingatMohawk Member Posts: 1,021
    The union looks like it is brass, which is softer than an iron based fitting. Be careful to not make things worse, especially creating "low spots".
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    soap won't hurt on the mating surfaces, if you wipe most of it off -- but it's mainly useful as a lubricant on the threads.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mattmia2
    mattmia2 Member Posts: 9,740
    Unless it is chunky, something on the mating faces isn't going to hurt anything but it won't help either. I would use a touch of pipe dope on the threads and on the back of the unions where the nut rotates on the back of it but anything that lubricates it will help it from seizing up. Anti-seize or modern types of dope or oil will stay in the threads and make it easier to get apart later.
  • Jamie Hall
    Jamie Hall Member Posts: 23,430
    BRAV)O! And thanks for the update.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • MikeAmann
    MikeAmann Member Posts: 998
    See, it wasn't as hard as you thought.
  • hot_rod
    hot_rod Member Posts: 22,254
    If the face and seat is scuffed up badly, then smear some pipe dope on both surfaces

    Any lube on the threads, plumbers stem lube, even chap stick will allow the threads to twist smoothly together
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • nicholas bonham-carter
    I think a little liquid dish soap on the mating surfaces and union threads would be better than antiseize,, or pipe dope.—NBC 
  • billvedovato
    billvedovato Member Posts: 1
    A basin wrench will do it. They're made in a couple of different sizes including big enough to tighten that union. I've been using one for all manor of heating repairs through the years. The jaw is thin enough to get into tight spaces and the handle swivels. DON'T BUY A CHEAP ONE!
  • Kiwi
    Kiwi Member Posts: 6
    I suggest going to a engineers shop. Asking for a not of 3/8" or 5/16" or preferably 1/2" scrap steel plate.
    Then work out the angle you need and make the spanner your self.
    A good spanner doesn't need to be flash looking to be able to do the job.
    It may take a bit of time but hey, all you are needing to do it to turn it a very short amount to be able to get a conventional spanner on it for the next stage of the nut's revolution.

    The other possible options, MAYBE, is to get to it, from the other side of the nut. Cut a hole in the floor or rear wall, or maybe both. (been there, done that, a couple of times.

    I look forward to reading how you managed to 'sorted it'.

    Kiwi Will.
  • george_42
    george_42 Member Posts: 121
    I use a chisle and hammer and drive nuts off or on when access is limited