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How to remove stubborn pigtail?

I've been having some trouble with the pressure in my boiler, and I suspect a clogged pigtail. I tried to remove it today and replace it with a new brass pigtail and add a low pressure gauge (as per suggestions I found on this board), but I can't seem to get the pigtail off.

I first tried unscrewing it by hand (carefully) , but it didn't budge. I then experimented with putting a pipe wrench on it, but it's so small that I feel like even my 10 inch wrench is going to collapse it and/or egg it rather than turn it. I then hit it with some heat (that seems to work sometimes on radiator spuds), but no dice. I then thought that I could perhaps remove the bushing, but I couldn't move that either.

It seems like my options at this point are:

<ol><li>Cut the pigtail off and rethread the end of it (it's black iron)

</li><li>Cut the pigtail off and then cut it out of the bushing (like a radiator spud)

</li><li>Cut the pigtail off and use an internal pipe wrench on it

</li><li>Try a strap wrench (but will I get enough torque?)

</li><li>Put some liquid wrench or some penetrating oil on it and see if it loosens things up

</li><li>Put a pipe wrench on it anyway and hope for the best


Which of these is the best option? Or is there something else that I've missed?


  • Removing pigtail

    If you disconnect the wiring of the pressuretrol, is there enough clearance to unscrew theat from the pigtail? When the p-trol is off, then use the jaws of the pipe wrench around the flat of the loop, and see if that gets you enough grip.

    This will show you how important it is to have mostly brass, and bronze fittings screwed into the boiler, Avoid plugs wherever possible, and instead use short brass nipples with caps, so they can be removed later if necessary.

    A union under the pressuretrol will allow you to avoid the disconnection of the wiring for the annual cleaning.--NBC
  • Sethamin
    Sethamin Member Posts: 36
    Pressuretrol too close to remove

    Unfortunately, the pressuretrol is too close to the boiler to be able to spin around. To your point, though, I was planning on replacing the entire connection in brass and adding a union to avoid this problem in the future. But I need to get this one off first!
  • Badly placed pressuretrol

    You may have to spin the whole assembly off, which must have been the way they put it on. Afterwards, you can then separate the old pigtail from the pressuretrol, and go from there.--NBC
  • BobC
    BobC Member Posts: 5,227

    you can use the method I used on my old v75 boiler. The pressuretrol had become intermittent and i picked up a NOS mercury bulb vaporstat for not much more than a new pressuretrol would cost.

    My pigtail seemed like it was welded in place and i didn't want to snap it off if I could avoid it. I used a Jorgenson wood clamp on the loop and managed to get the thing to move. This type of clamp is amazingly strong, if you don't have one maybe you can borrow one (they are not cheap these days). The key is to use steadily increasing pressure (it will take a lot of it) until is breaks free. When I put it back I used teflon bearing pipe compound so it would be easy to remove. Then i had the new Smith boiler installed I replaced the pressuretrol with this vaporstat.

    If you can't swing that whole assembly off you can disassemble the fitting/bellows assembly from the body of the pressuretrol by removing the 4 torx screws at it's base. Getting it reassembled is a bit fiddly but it can be done if your careful.

    Good luck,

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Pughie1
    Pughie1 Member Posts: 130

    I'v had good luck inserting something long in the circle of the pigtail such as the handle of a pipe wrench, or a heavy duty screwdriver, even an 18" x 1/2" pipe nipple works nicely. In your photo  you would put your device through from the left side facing down. Then GENTLY try prying counterclockwise. I stress "GENTLY", not the best time of year to snape it off. What does Dan say about the old spincster (?) muscle? This may help.

    John Pughe
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,375

    I use Pughie's technique. I have an 18" piece of hickory I cut from a broken shovel handle that comes in handy for this kind of thing. I put it through the loop and turn. It hasn't failed yet.

    If the pigtail breaks, you can use a socket wrench on the bushing. I wouldn't bother trying to re-use that bushing if you can find a new one.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • Pughie1
    Pughie1 Member Posts: 130
    Old Hickory

    "Old Hickory", great idea Hap!

    JUGHNE Member Posts: 8,924
    edited December 2013
    Impact wrench

    I would cut the pigtail off enough to get 6 point impact socket (not 12 point) on bushing.  First spray with PB Blaster,  sharp pick tool to cut now softened pipe dope, spray again & let sit awhile.  Then impact tool on socket.. If not then chisel time as on the rad spud or drill out for larger internal wrench and impact on that wrench.   Even a 1/4" 18volt impact removed an electric water heater element that would not budge with a 24" breaker bar on socket.
  • j a_2
    j a_2 Member Posts: 1,796
    cut it

    I would cut it off,ream it down try a left handed drill bit or a snap on grade easy out..maybe retag it and be done with it…..Total time 30 min...
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,375
    How is PB Blaster going to penetrate the thread sealant?

    I hear this kind of recommendation all the time, but it just plain doesn't work. The threads are sealed. PB Blaster will just leave an unpleasant smell lingering in the basement for a few weeks.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
    JUGHNE Member Posts: 8,924

    has worked most of the time for me.  The first spray allowed to soak has softened up the exposed pipe dope, then the pick & scratch would expose more hard dope and another spray would work on that; I repeat until what is visible is gone and the final spray does seem to go into the threads.  But there are many types of pipe dope.  Maybe I've been lucky so far.  Yes it has a unique distink.
  • Sethamin
    Sethamin Member Posts: 36
    Great idea!

    This is a great idea! I'm going to wait until we get a warmer spell of weather again before I try it out, but I'm really bullish this one will work.
  • Sethamin
    Sethamin Member Posts: 36
    Just to close out this old thread, I ended trying Pughie's suggestion and putting a length of pipe through the middle of the pigtail, and it worked like a charm. Thanks!
  • icesailor
    icesailor Member Posts: 7,265
    Teflon Tape and paste is a wonderful thing.

    Even after 40 years, that pigtail would have come out with a 12" pair of channel locks.