I am rehabing a small 1940’s house, 2 BR, 1 bath and tiny kitchen.

The intent was for only cosmetic updates. BUT !!!!

The water pipes had all been replaced with copper. And the DWV in the basement was all ABS and it coupled to a soil stack in the wall.

However, the connections from the kitchen sink and bathroom lav had been disconnected from the soil stack and S traps installed through the floor and ran to a separate branch that combined with the toilet/tub branch. The toilet tub branch was vented by the soild stack.

While there where code issues with venting the kitchen sink and lav and the use of the S-traps it seemed to work OK and I would have like to leave it alone.

I posted a question here a while back about installing a basin pump for a basement washing machine drain and found out that I needed to tap the soil stack for a vent or run a new vent through the roof.

Also the orginal vanity drain was lead and it was just “bent off” and appeared to have a crack in it.

And the plan was to replace the vanity with a pedistal sink.

Thus I decided that I need to open up the soil stack, add a vent, and restore the orginal drain connections to the lav and kitchen sink.

I had opened the upper part of the wall to see what I was deal with and it was CI and in good shape. TOO GOOD of shape. It was too tight to a stud and finished wall on the other side that was not to be desturbed.

I could not get a CI pipe “snapper” around it.

By this time I had pulled the toilet and cut out the lower part of the wall. The bottom 18″ from the lav san-t was was rotted. Now I now by the “repairs”.

So manny carbide blades latter I get through 90% of the soil stack.
But I still have problems get it to let go.

After wrestling with it it finally starts to give. But still have problems gettting it out. I had disconnected the rubber coupling at the bottom to the ABS part and had even cut it part the way through.

But finally 2 of up twisting and lifting got it to come free.

And out the bottom, along with a couple of gallons of rust was a 1.5″ piece of ABS pipe.

Then I go down to the basement to see what in the h*ll that was connected to.

The stuff was 3″ run and it ended in 90. Connected to the 90 was a 3 to 1.5″ reducer. That was all glued together. But then an 18″ piece of 1.5″ was stuck up the center of the old CI and through the rust.

Then a rubber 4″ to 3″ coupling had been slipped over the joint the CI to the reducer. How they got it over the “hub” part of the fitting I don’t know.

Actually I all “kind of worked” OK. With that small of house the 1.5 seemed to vent OK and since the CI was now dry it would last a while.

The main problem was that the only thing “sealing” the bottom part the CI stack the amount of rust that was packed between the remains of the CI and the 1.5 ABS inside of it.