OK. First, I'd like to say THANK YOU to anyone who helps me with this.

Second, I'd like to say **@$&%$##$!! +*&%$$&*(%^-ing Cast Iron **%#$@^*((! ing pipe in the $*^&%$%^&*^$%*#ing floor!

There. I feel a little better.

So here's the problem I have: 60+ year old house, old iron and galvanized drain pipes.. The drain line from the kitchen sink runs about 4' across the basement ceiling, then straight down into a cast iron pipe that runs under the concrete floor over to the main line, then out to the street. The 'across' piece finally gave out, and I went to replace it.. In getting the old pipe out, I have somehow managed to snap the old cast iron fitting off flush with the floor. There is nothing I can connect the new pipe to.

The only thing I can think to do is go rent a concrete saw and cut out a section of the floor, then hook new pvc back up to the old line with a Fernco boot, then re-pour the concrete around the repair.. It sounds fairly straightforward.. What am I missing?

What are the pitfalls and problems I need to avoid here?

HELP!

Thanks!

You can jack hammer just around the pipe enough so you can slip on one of these collars. http://www.fernco.com/files/installation-instructions/pipesleeveseals.pdf

I don't think you need a concrete saw. I think you need an electric pavement breaker (jack hammer). Break out concrete around cast iron pipe. When you get though concrete you should find a 90 degree turn. Using a drill and a bit slightly smaller than the difference between the outside of the pipe and the inside of the fitting and drill out the lead in the joint. Drill lots of holes around the pipe then pry out the lead. Lead is soft and drills easily. Remove remainder of the cast iron pipe and using a rubber gasket insert a PVC pipe.
The problem I see with using a rubber coupling to connect pipes is getting the cast iron cut reasonably straight.

Thank's for the quick responses!
The problem is that the whole joint snapped off flush with the floor. The 'bell' part of the connector stuck up about 1/4 inch over the floor, and when I sawed through the galvanized pipe over it, it just snapped off. The 90 degree elbow is broken pretty much in the middle of the bend, so I think I'll need to dig down to where it straightens out.. Maybe I'll be lucky and there'll be a connection under there I can just remove without having to cut the iron pipe... A guy can hope, right?

So what other mistakes do I need to avoid?

If you have a 90 that has broken you should be able, after removing concrete and soil around it, to break away the remainder. Cast iron breaks away fairly easily when struck from the inside outward. You should then be able to connect a PVC street 90 with a shielded rubber coupling.

Thanks everyone for your help!

As it turned out, once I removed the concree from around the broken pipe, I found that the broken 90 connected to the next section of pipe just a few inches down the line. Since the bell on that connection was intact, I just used a MAPP gas torch to melt out all the lead, removed the broken pipe and cleaned out the bell. I used a Fernco pipe doughnut, and connected new PVC directly to the old cast iron. After that, it was just a matter of assembling all the new PVC parts to finish the original repair.. EASY!

Thanks everyone for all of your help!

Congratulations and kudos. I would have been afraid to use the Mapp gas torch. Afraid that the heat would have cracked the cast.

Good job !