How to break free "threaded cast iron" plumbing

[Tidybuoy]

PROJECT SOLVED! Pics added at end of thread.

If worse comes to worse, I will use a rubber Fernco Cupler. My OCD says to try and remove the original fitting first.

I'm replacing the kitchen drain plumbing and I had to cut out the vent pipe. I will be replacing all of the drain piping from kitchen sink to sewer line - plus adding a cleanout. The original galvanized section (not shown) was rusted out and leaking.

The 45 degree elbow is not moving. I used WD40 and soaked for a couple of days, I tapped with a hammer to "wake up" the fitting, I used a torch on it but it is not budging.

Anyone with advice? See photos below.

[oldE]

Just cut it all out.

[908/930]

More torque, just need two longer pipe wrenches.

[stevej37]

I had the same problem a year ago. Big pipe wrench with a four foot pipe over the handle solved it.

[unclebilly]

WD 40 specialist. It’s not like the original WD 40 at all. Pretty incredible stuff.

[unclebilly]

WD 40 specialist. It’s not like the original WD 40 at all. Pretty incredible stuff.

[peppy]

A 36" pipe wrench is an amazing tool. Get the aluminum one if you can find it.

[jyl]

The lower part should give lotsa leverage?

[herr_oberst]

Every floor jack sold comes with a free long cheater bar.

[Tidybuoy]

Originally Posted by peppy

A 36" pipe wrench is an amazing tool. Get the aluminum one if you can find it.

I have two very large pipe wrenches - both about 24" long. One is aluminum and much easier to carry around. I will try the long pipe added to it.

[cabmandone]

Did you try cussing at it? Ya need a BFPR for that job. Me, I'd slap a fernco on that thing in the blink of an eye. It's a vent.

[herr_oberst]

Originally Posted by cabmandone

Did you try cussing at it? Ya need a BFPR for that job. Me, I'd slap a fernco on that thing in the blink of an eye. It's a vent.

Plus 1.

[aschen]

Probably not appropriate here but still one of my all time favorite memes

[onewhippedpuppy]

Originally Posted by peppy

A 36" pipe wrench is an amazing tool. Get the aluminum one if you can find it.

Amen. Worst case you can beat the hell out of it when you get mad.

[look 171]

Like many have said here. Sawall it out, no hub connector and abs is your friend.

[Arizona_928]

Sawzall the pipe right at threads. Then use the sawzall to cut perpendicular of the threads into the pipe that is in the fitting. Once enough the of the material is removed, chisel the threaded section of the pipe into the fitting thus releasing the tension on the threads. Or cut it any point and use one of the rubber connectors with hose clamps and add sections of abs as needed.

[Porchdog]

Big pipe wrenches will get that loose. I'm used to having 36"s on the truck. There are two 60" at the shop. Pipe cheaters and come-a-longs as necessary.

That fitting looks more like forged than cast. When they are cast you can break them with a big hammer.

Some of the old buildings around here have 6" and 8" threaded fittings. You can't always demo those out, so you need to get them apart - if only to put a threaded flange or flange to groove adaptor on them.

If you can do it safely, oxy-acetylene on that fitting will loosen it up. The fitting needs to glow.
There could be hard-setting dope on the threads, which makes things more interesting, but heat will help with that as well.

Aluminum pipe wrenches are nice, but don't use pipe cheaters on the handles.

[cabmandone]

I think Porchdog has your answer in his third sentence if you don't want to go Fernco. Whack that fitting with a hammer and put a PVC female pipe thread adapter on the vertical pipe. But I'd still pop a Fernco on it and move on.

[Porchdog]

Hey Cab - If that fitting is cast, there's a very good chance he can bust it with a hammer. I think it's forged - and if it is forged, busting it with a hammer is going to be tough.

If pipe wrenches plus cheaters aren't doing the job, I would heat the fitting until it glows. That's if I felt good about protecting the stud and wall behind it. If heat seems like a bad idea - you can saw it off.

[javadog]

Get a helper, use two pipe wrenches.