Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Fixing a crack in the cast iron

One of my antique radiators has started leaking from a point that doesn't appear to be a joint, seam, or connection. I'm assuming there might be a small crack in the cast iron (it's been moved around a number of times during a reconstruction/rehab). Because it's an antique and fairly unique, I'd like to try and fix it but I'm not sure who can help. I did call some local radiator specialists, but so far none of them have thought it was something they wanted to take on.

Does anyone have any insight into the types of companies I might try for help? Since it's cast iron, could a local welder be able to patch it, or an auto body shop? Any help would be appreciated. I'm in the Chicagoland area (west suburbs), if anyone knows of any locals that might be able to assist.



    JUGHNE Member Posts: 10,905
    Assuming this is a hot water system, what pressure do you run at? And is your gauge accurate?
    I had a customer with a dripper rad, it turned out his expansion tank was water logged and his relief valve was near the 30 PSI opening point. At 12 psi the leak stopped.
  • Jamie Hall
    Jamie Hall Member Posts: 22,147
    If this is steam, I suggest JB Weld. Not pretty, but it works. The trick to it is to get the surface where you are going to stick the stuff perfectly down to bare metal. I'm not sure whether it would hold against water pressure for a hot water system, but it would be worth trying.

    Welding cast iron is a fine art
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Gordy
    Gordy Member Posts: 9,537
    Welding cast iron is doable. You just have to follow proper procedures to do it.
  • hot_rod
    hot_rod Member Posts: 20,790
    If you can locate the crack it is certainly weldable. i use this site all the time for unique welding stuff.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream