How do you disconnect cast iron pipe from hub with compression gasket

[Artie_T]

Hi Everyone,

I need some help ASAP. I live in a 1970's ranch home on a slab. The main bath started to leak so we decided to replace it with one of those surrounds that comes with the tub. Once I removed the tub, I discovered that the cast iron street Y going into another fitting that heads to the main line was rusted & cracked.

This is where I'm asking for your help! How do I disconnect the broken end of the cast iron pipe from a hub that used a compression gasket inside the hub to make the connection 40 years ago?

Any suggestions or thoughts would be greatly appreciated.

I am also concerned that the joint may have pertinently fused itself closed with rust. Does this happen?

Thanks again,
Artie.T

 

[Zeppelin5000]

When dealing with old cast iron fittings, it's best to cut that old stuff out and replace it with no-hub couplings and PVC.

 

[frodo]

beat it with a hammer..smash/ break old pipe/fitting .or, use a 4 1/2'' grinder with abrasive wheel, to cut it out, ....add a new pvc ffitting/pipe using a




note the brand name,,and item #..cast x plastic [ci x pl]

do not use a fernco,,pipe will be misaligned...

 

[Artie_T]

I know you guys are right, but is there another way?

I cut out the upper half of the broken pipe and now need to remove the lower piece that is held inside the hub of a good fitting using one of those rubber donuts. I tried to drill it out without much luck, it just left a lot of black dust around the fitting and the rubber just bounces back and the bit doesn't go the full length of the hub.

The pipe runs under a wall into my homes main hallway. I don't want to have to remove the rug, cut the slab, dig a ditch in the hall and cut into the cast iron main unless the current pipe /work site breaks in the process of removing the piece of pipe from the hub.

I was thinking about trying to heat the inner pipe piece with a torch to melt the donut some, causing it to release. Do you guys think this will work or is this a bad idea?

 

[frodo]

heating that pipe will not hurt a darn thing.

be advised....torch,,,,wood, insulation, fire hazard.

keep your head on a swivel, have a extinguisher handy...or a garden hose,,,with a sprayer..turn the hose on

so if you fug up...all you gotta do is point and spray

heat it up,,,dig it out with a screw driver..when you g back with a gasket

buy one called EZTITE...cause they be easy!!!

when your done,,,you have melted the tar coating on the outside of the pipe.

protects it from rust...paint it with tar...or something,,krylon...to keep it from being ate up

 

[Artie_T]

Thanks again Frodo.

My game plan for tomorrow is get some 6-8" drill bits and try again, then maybe the torch or try cutting it from the inside in a few places.

I also posted this question on some other plumbing forums that were no help. I received one word answers like "Dig". For me digging is my last option, one that I will do if nothing else works.

My father was a plumber and after he pasted I didn't have it in my heart to get rid of his old 4' cast iron pipe splitter or his 3' pipe wrench. It always reminder me of the type of man he was having to work with these giant tools. (I think you are one of the same)

Thanks again.
Artie.T

 

[Artie_T]

I'd like to thank all of you that replied to my post. I read all the suggestion and was looking for some reassurance in some of the ways I was looking at tackling this problem.

I am happy to tell everyone that I was able to get the broken pipe out of the cast iron hub after about two and a half hours, three 1/4" drill bits, and trying to use a trigger clamp in reverse as a spreader with one arm on the hub and a chain attached to the other and the broken pipe (got it to move about 1/8").

At that point it would wiggle a little bit, but still would not come out and that's when I went for the torch. I brought the garden hose in, turned on the bath fan and started to heat it up from the inside of the broken pipe and 15 minutes later I had it out!

Thanks again everyone.
(with a special thanks to Frodo, I was concerned about using a torch in a wast line with a chance of methane gas.)

Artie.T

 

[frodo]

no worries...i blew a man hole lid in the air about 3' one time,,it was loud and cool!!!!

 

[Mr_David]

no worries...i blew a man hole lid in the air about 3' one time,,it was loud and cool!!!!

Okay tell us the story now. I'm gonna go get some popcorn.

 

[frodo]

we were warned not to smoke around the man holes on Mcdowell ave,,,Joe, the boss's son,,got a cable hung up in a main of a barber shop

so I popped the man hole cover to see if it was hung up there,,just for ****s and grins,,,and because we were told their was gas

i dropped a rag with glue on it, lit into the hole.

what happend next,,,was not expected at all..flame shot up out of the hole about 3 feet and the man hole cover across the street jumped up

the boom sounded like a cannon..We put the covers on and got the hell out of there before it could be blamed on us.

sure enough, 5 minutes later, blue lights were looking for some kind of gun shots...we played like schultz
we know NOTHING!!!!

Joe snitched us off to his daddy,,we got lectured,,,scolded,,
do not bother too ask for a raise for 6 mths LOL

 

[JohnTheApprentice]

If youre wanting to re-use the existing hub, ive tackled this dilema many different ways because each situation is different...sometimes ive been able to grab the piece im trying to remove with a pair of chain cutters and get enough of a bite on it without it crumbling to gently wiggle it out of the existing good hub...its risky because you can damage or break the existing cast iron hub and fittings...another way, since the pipe youre removing is cracked, eroded, etc, try breaking it with a hammer up flush to the existing hub(be careful not to break hub with hammer) if you have a sawzall handy, cut the remaining cast iron thats inside the gasket using a cast iron blade, the use a metal cutting blade to cut the gasket(just the gasket) all the way through. you will feel your blade hit the hub when youre through it...you can make two cuts through the gasket opposite of each other to make the removal easier...grab the gasket with a pair of chanel locks and removed it....you will need a proper sized replacement gasket, lubricant, as well as some strenth to insert the new pipe...if youre replacing the section with pvc pipe, you will need to bevel the end of your pvc pipe or youll never get it to seat inside the rubber gasket properly...this being said, if you have easy access to the hub, id cut it off, and replace up to it with pvc pipe, and just use the proper sized Fernco to adapt to it existing pipe...much easier! Good luck!

 

[Mr_David]

i dropped a rag with glue on it, lit into the hole.

what happend next,,,was not expected at all..flame shot up out of the hole about 3 feet and the man hole cover across the street jumped up

Now that's Funny.