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4" cast iron to pvc hub

6551 Views 11 Replies 5 Participants Last post by  Javiles
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Long time reader and have found many great solutions on this site.This time I am really stuck and have to ask for some help.

I am building a 4" pvc stack for a toilet, and I am connecting to an existing 4" cast iron pipe protruding from the foundation wall. Before I was aware that there is rubber donut(aka a ty seal) that can be pushed into the cast iron and accepts pvc, I was told that I need to cut off the bell end of the cast iron and use a 4"x4" banded gasket. Well I cut off what I thought was the bell end of the pipe, but really only the lip of the bell. Only about half of the whole bell protrudes from the wall, so I can't cut the whole bell end off.

My question is, can I still use the rubber hub even without the whole bell end? attached is a picture of the hub adapter I am considering using, and the other is my bon-doogle of a situation, showing what was cut off.

Any suggestions on how best to tackle this would be greatly appreciated.

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Ouch! You need all the hub to use the doughnut.
Can you get to the other side of the wall and connect to the pipe?
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other side of the wall is the driveway, so it is not easy to get to. is there a hub that seals to the inside of the pipe wall
is that straight pipe or a fitting? if its pipe youll need to break that wall out so you can get a clean cut, then you can use a no hub coupling with a no hub adapter for your transition. cutting that pipe in a recessed wall can be tricky but not impossible. have done it many times, i use a high speed cutter with a metal cut off wheel. find a way to test seal on the coupling after joining can be a problem area if you end up with a blockage in that line. do not use a fernco what ever you do.
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Thank you javiles. That seems like alot of block to knock out , and a difficult cut. Can i slip a 3" pvc in there some way?
Any other suggestions how to cut the pipe in the wall, I dont want to knock out too much block. Maybee a 3" cutoff wheel?
You just need to break enough block to get the no hub coupling over it, and be able to tighten it with a ratchet. use a small cut off wheel and cut from the inside out. youll need a straight shaft cutter. done it a million times.
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Yeah Javilles is correct. Just break the block back away from the pipe to give yourself room to work. Dig out the dirt around the pipe and cut the pipe off. If you own air tools a die grinder rigged with an arbor, and a steel cut off wheel will work well here, it will just take some time and a few beers. When you adapt to PVC use a Fernco or Mission coupling, not a no-hub coupling, and wire wheel the outside of the pipe to make it smooth for the coupling.

Install a real clevis type pipe hanger suspended by min 3/8 all-thread right inside of the coupling, A 2 x 4 with a hole drilled makes a good top end hanger, just screw it to the joists with two 3 inch # 14 screws on each end.

A Masons hammer and a small trowel are good tools to pick up here. You can brick in around the pipe with mortar, then fill any voids with mortar.

Make absolutely sure you have all stainless draw-bands on your coupling.

I like the Mission HD couplings with four bands.

Good luck.

PS The Bell on a 4 inch Bell and Spigot pipe is about 3.5 inches deep, the rim you cut off is just the rim. I'm surprised you didn't look into the pipe before cutting? You surely would have seen where it reduces in size. Measure twice, cut once, not the other way around, or was that new saws-all the wife bought you just too tempting? :huh:
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Javiles, Jagans-Thank you for all the advice. I was able to cut the pipe from the inside with an arbor bit and about 8 3" cutoff discs! Took about an hour with the drill, but couldnt get my hands on a straight shaft cutoff.

Jagans-rookie mistake not looking into the pipe first, but you seem to work a little faster(read careless) when youre only working toilet is down!

Thanks again, thought I was really up the creek

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Looks Good! thanks for keeping us in the loop of your project. :thumbup:
Id cut it farther past the wall into the dirt and make your connection,you don't want a joint buried in concrete.
And whatever you do pitch the fernco and get a no hub coupling to install in place of it:)
is that straight pipe or a fitting? if its pipe youll need to break that wall out so you can get a clean cut, then you can use a no hub coupling with a no hub adapter for your transition. cutting that pipe in a recessed wall can be tricky but not impossible. have done it many times, i use a high speed cutter with a metal cut off wheel. find a way to test seal on the coupling after joining can be a problem area if you end up with a blockage in that line. do not use a fernco what ever you do.
Suggested.. he went with this option.
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