Plumbing and Piping - Broken drain pipe-best way to fix?

A galv. steel 21/2" drain pipe goes in to the basement floor. It cracked on the bend. I dug out around the break, it connects about 12" after the bend to a larger, maybe 41/2" pipe. Is the 21/2 pipe threaded into the larger pipe or is it pressed? Since the house was built in 1929 the pipes are very corruded on the outside. The 21/2" pipe is shot, but the larger pipe looks like it is in good condition. What is the best way to repair this?

My best guess would be that the larger line is cast iron and the smaller line is either threaded into it or they cheated a made a lead joint. You'll have to uncover where the lines come together and see if the smaller line goes into a "hub" on the larger line. The hub would be quite a bit bigger than the small pipe and if you scrape around the small pipe where it enters the larger line you'll see lead if it is a leaded joint.Have to ask about where the break is. You said it cracked on the bend. Are you saying the pipe has a bend in it or a fitting? If the pipe is bent you are going to have a time matching it for a new line. Good luck and post back.

I got to the pipe where it meets the larger drain pipe and it appears to be threaded. I am going to try to pick it out of the larger pipe. I have cut the 2" pipe about 3/8 of an inch from where it enters the larger pipe. I will cut a straighr line down the remaining 2" pipe that is inside the larger pipe, being careful around the threads and then try to pick it out. Your concern of the bent pipe is acurate. I do not know where to get a piece like that. But I first have to worry about getting the remainder of that pipe out. Any other ideas? let me know. Thanks

In my opinion, you're just getting yourself into a real headache in trying to "repair" that 75-year-old cast iron/galvanized stuff, especially with a bend in it.
I would cut the 4" cast iron and install a PVC white plastic fitting with no-hub connectors with a T or Y to the 2" galvanized. You can connect the galvanized and the PVC with a Fernco coupling. Connect the PVC to PVC with PVC primer and glue.
You can cut cast iron with a reciprocating saw with metal-cutting blades or a snapcutter made for the purpose. You can cut the galvanized with the recip saw. You should be able to rent either.
No-hub connectors have a stainless steel sleeve over a neoprene rubber sleeve and two ss clamps. A Fernco coupling is just a neoprene rubber sleeve with large ss hose clamps.
Go to a plumbing supply store and have a measured drawing of what you need to do, and they should be able to make it up for you.
Good luck!
Mike

Mike has the best idea. If the bend isn't TOO extreme you will be able to get alignment with the Fernco fitting. Good luck and let us know how it went.

I would like to do it Mike's way. I was concerned that using Ferco couplers would not be code since it would be under slab, but I guess that wouldn't be my problem 50 or so years from now. Have you ever heard of anyone using a Ferco coupler and then cementing over it? This way would save me alot of work.

Fernco's are to code on drain lines.
I don't know how long it would last under concrete (or even if it's allowed), but it would work for a very long time anyway.
Good luck!
Mike