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Left Right Radiator Nipples

lza Member Posts: 40
I'm looking at 6-12 leaking cast iron radiators with threaded L-R nipples joining the sections.  I would love some ideas. 


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,578
    Where are the leaks?

    Are these in place?

    Was this a freeze up?

    Are they joined up top and bottom?

    If they are used, and on the scrap pile, the price would be pretty cheap, so you could take a chance, as I believe these nipples can still be found. Cut the nipples through, and remove the remains from the section tappings. Then you can determine whether the threads are standard size. Clean up the section tappings with a tap of the right size, and reassemble with the new nipples. If the nipples rusted out, then all of them should be replaced.--NBC
  • lza
    lza Member Posts: 40
    No fin tubes please


    -Yes, these are in place.  A beautiful old old school.  Some are 15 feet long and they are wall-hung!  Taking them down will require some engine hoists and rigging.  

    -No, it wasn't a freeze up.  They're just plain old. 

    -They are joined top and bottom.  The problem is that each section butts up tight to the next.  Each threaded nipple has a couple of internal...nubs, landings, whatever you want to call them, just like an old thermostatic trap spud.  Every four sections or so, there is a longer l-r nipple joining another group of sections. 

    I can have one of the machinists fab me up a removal tool, if I break one apart and can get to the nipple, but I'm doubtful that those little internal nub will hold up to being wrenched on after decades of corrosion. 

    Another last ditch option is trying to weld the cast iron.  This isn't something I would look forward to because of how finicky welding cast iron is, and fears about future cracking with all the expansion and contraction. 

    Maybe epoxy? 

    If a good solution can't be found, upper management wants to take them out and put in fin tubes.  Yuck.