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best penetrating oil for a rusted plug?

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Doug_R
Doug_R Member Posts: 9
in Radiant Heating

I have a Y-strainer that hasn't been cracked open for years. I've tried WD-40 Specialist Rust Remover over several days, but no luck so far. Here are two questions:

1) What brand of penetrating oil do find works best for hydronic systems?

2) To open the strainer, I could use two pipe wrenches; the second one pulls in the opposite direction to stabilize and reduce torque on the pipes. I'd like to try an impact wrench on low setting. In other situations (e.g.: rusted lugnut), high-frequency, low-duration impacts work better than a strong-arm . I would still use the second wrench to stabilize the connected pipes.

  • Any thoughts?

Comments

  • Intplm.
    Intplm. Member Posts: 3,050

    Pb Blaster. I have had some very good luck with it.

    There have been a couple of times when a heated-up fitting and pressing/melting a crayon, yes, I said crayon, into the heated joint can work well too. Take the one from the coloring book box that never gets used. 😉

  • pecmsg
    pecmsg Member Posts: 7,142

    When new pull the strainer nut and never seize it.

    What size strainer. Maybe replace the whole thing!

    Intplm.
  • Doug_R
    Doug_R Member Posts: 9

    Crayon—it makes sense, because the wax can wick up into the threads and is also a lubricant. Thanks!

    Intplm.
  • Intplm.
    Intplm. Member Posts: 3,050
    https://forum.heatinghelp.com/discussion/comment/1895921#Comment_1895921

    Excellent. If you do try it, please post your results.

  • mattmia2
    mattmia2 Member Posts: 17,031

    I have never had penetrating oils un-seize something that was seized. it can make it easier to unscrew it over the rusted threads after you break it loose but i've never had it loosen something. beating on it, beating on it with an air chisel, beating on it with an impact wrench, heat, proper tools to apply a lot of torque to it will get it loose.

    Doug_RethicalpaulAlan (California Radiant) Forbeshot_rod
  • Doug_R
    Doug_R Member Posts: 9
    https://forum.heatinghelp.com/discussion/comment/1895920#Comment_1895920

    The strainer is on 1-1/4" pipe.

    del strainer.jpg
  • pecmsg
    pecmsg Member Posts: 7,142
    https://forum.heatinghelp.com/discussion/comment/1895927#Comment_1895927

    2 Wrenches but probably easier to replace.

  • Intplm.
    Intplm. Member Posts: 3,050

    That plug…3/4" or 1/2" ? should come out. Pb Blaster? Apply it often over time if you have the time, and try it after a couple of weeks.

    I'm thinking you don't even need to do that. A couple of 18" or larger pipe wrenches should unscrew the plug as is.

    Doug_RAlan (California Radiant) Forbes
  • mattmia2
    mattmia2 Member Posts: 17,031

    that will probably unscrew with the right wrenches. the plug to just flush it should be easy, the cap to remove the whole strainer will take more force.

    Intplm.
  • mattmia2
    mattmia2 Member Posts: 17,031

    could replace the plug with a boiler drain and hose thread cap to make flushing much easier.

    Intplm.
  • Mad Dog_2
    Mad Dog_2 Member Posts: 8,585

    ZEP 45. Mad Dog

    Consulting by Mad Dog & Matt Jr.
  • Doug_R
    Doug_R Member Posts: 9
    https://forum.heatinghelp.com/discussion/comment/1895934#Comment_1895934

    Thanks for the idea. I'll try that.

  • kcopp
    kcopp Member Posts: 4,692

    Heat. Kroil.

    Larry Weingarten
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 4,751
    edited May 6

    I never understood why plumbers install strainers with a plug instead of a bibb drain. See it all the time.

    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    mattmia2Doug_RIntplm.
  • hot_rod
    hot_rod Member Posts: 27,613

    What type of piping in the system?

    Do you really need a Y strainer? Looks like it has never been drained or disassembled?

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 20,302

    Kroil Oil is the best IMHO.

    Y strainers are difficult to get the wrenches on especially in a tight spot.

    I would unbolt the flange below the strainer and unscrew the strainer off the copper adapter.

    Then you can put it in a vise and get the plug out. I would also while it is out remove the bushing and take the screen out and clean it. Put everything back together with teflon tape and "Never Seize" as @pecmsg mentioned and a drain valve instead of a plug. You are in an awkward position with the strainer vertical and the wall to get leverage on it.

    Doug_R
  • Doug_R
    Doug_R Member Posts: 9

    Ed, that is great advice (to "unbolt the flange below the strainer"). Get that strainer away from the pipes and walls and entanglements, and work on it in a vise. I wish I'd seen it\\your comment earlier.

    I was able to get an electric impact wrench with an oversize socket on it. The frequent, short bursts smoothly did the job. The strainer was packed with magnetite. It feels so good to put it back clean.

    Thanks to each of you for your advice and insights.

    Doug

  • hot_rod
    hot_rod Member Posts: 27,613

    if the system is empty, heating the casting seems to always loosen stubborn threaded connections

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream

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