Removing a boiler plug

boiler_man

Hi any body have any tips & tricks to removing a 2inch plug from a scotch marine boiler? (plug has been there for 16 years)

Steamhead

Two words:

Impact Wrench!

icesailor

And if that doesn't work,

tale a 1 1/4" hole saw and drill a hole through the middle of the plug. Take a sawzall and CAREFULLY saw to the edge of the threads of the plug. Saw slots at 12: O'clock, 4: O'clock, 8 O'clock and then one between 4 and 6 O/clock. Take a big screw driver and knock the piece out between 4 and 6. Then, the other pieces. Don't worry about minor scratches on the female threads. Teflon tape (That stuff that some hate but others find irreplaceable. Put lots of wraps of T-tape and use Rectorseal #5 or Rectorseal #100.

It's never failed me. I don't have an impact wrench or a compressor large enough to use a wrench on.

Charlie from wmass

Just watch the torque

when you try to loosen that. I have seen some turn out a section of iron when the plug is twisted. What kind of shape is the boiler in before you try this?

RDSTEAM

saw

works well if you cant wrench it out. slice the plug end off. put one cut in it, in an area where you can swing a hammer and a cape chisel. (cape's work the best but if you dont have one, a flat chisel is ok). you must cut the enitre length of the plug threads and deep enough to rip them out but not deep enough to mar the female threads. If it comes out extremely easy, then you know you probably got the female threads a bit. once cut, you fold one side down until it rips and then fold the other end inward. should then be loose enough to take the claw side of your hammer and spin it out.

Polycarp

persuasion

Heat helps if you can get it to the fitting.  There are lots of "break loose" fluids available at lots of hardware stores.  Some people swear by a certain brand, but I've not noticed any real difference. 



But I find that the key is the persuasion bar.  Get a length of pipe or hollow fence post and slip it over your wrench handle.  The added length gives you a lot more force.  Unlike an impact wrench, you can get a lot of torque without sudden shock .. or buying an impact wrench.  Be careful of the boiler itself though.  It's basically a big lever and you can end up moving the boiler if it isn't bolted down.

RDSTEAM

i dont think

moving the boiler would be possible. big scotch marine isnt going anywhere. be careful with the big bar though, if the head of the plug snaps you could be in for an extremely painful and anger filled experience.

Charlie from wmass

I always cut at least

two times if not three. I hope it is not a solid plug. If it is drill it out like Ice said. If it is hollow core cutting of the head will work.

icesailor

Removing Plugs:

I've dismantled about everything you could imagine. I'm into the low energy removal process. I've found that brute force isn't usually the best way to go. Too easy to get hurt. Because I always work alone, I have had to develop strategies that will work for me, alone. I have removed more rotted nipples from boilers than I could ever remember. I've removed them from water pumps. I have never resorted to any brute force. When I worked for someone else many years ago, we had some bruisers that could pick up some awesome things. I worked with a guy that could pick up and move anything. He never broke out a sweat. He just carefully and methodically, got the job done.

If you're dealing with CI fittings, it is really easy to crack them when you back it up with a big pipe wrench. I've cracked more than one. If it is in a critical place, I never put a wrench on it if I can't get it out with two 3' pipe wrenches. I get out the sawzall.

If you all don't know that you can drill a hole in a CI plug with a hole saw, you need to learn. Those hole saws drill through CI and steel like butter. A little oil is nice.

When I am roughing in and there are nails around, I use hole saws. They drill through the nails and keep right on going. I save my auger bits for the serious drilling. They are like razors.

The key to getting pipe ends and plugs out is to cut slots in the nipple or the plug, make a narrow piece that you can whack easily with a chisel and heavy hammer, and knock it out. Then, you relieve the compression tension on the nipple or plug. Then, you can unscrew it at your leisure.

Next time I need to do one, I'll post it.

I live in fear of breaking a piece out of a boiler when using an impact wrench.

Polycarp

give me a lever big enough

Don't know about a big Scotch marine, but with a 6' persuasion bar I can tip over a modern residential boiler with one hand.

Charlie from wmass

I would be most worried about

tearing out the thread not tipping the boiler.