Jeff,

In my experience, old galvanized steel pipe is usually rusted and
filled with corrosion (often down to just a pin hole), so it's very
possible the pipe or fitting will crack as you dissassemble it and
you'll have to keep removing pipe or fittings until you get
back to something solid.

That is my experience also and this is 80+ year old pipe. I am
close to the incoming connection which is buried.

Yep, I can relate... My mother in-law mentioned her kitchen faucet
was dripping. I though no big deal, I'd just change the seal or install a
new cartridge. Turns out the faucet was leaking around the spout which
naturally crumbled and broke off when I tried to unscrew it. So, it was
time to replace the faucet.

Unfortunately, it was an old wall mounted faucet. After a week of
hunting to find an affordable replacement, the pipes in the wall cracked
when I tried to remove the faucet connections.

So, I bought some special inside pipe wrenches to try and remove the
broken pipe stubs from the elbows in the wall. Of course, the metal was
so corroded it just crumbled and the elbows fell apart.

I thought, OK, I'll just replace the pipes running down the wall to the
basement. I literally just got the pipe wrench on the pipe and fitting in
the basement and it cracked at the fitting. I didn't even have to apply
pressure.

So, I decide to remove the bottom elbow where the pipe cracked off. I put
one wrench on the fitting, one on the pipe, and slowed tried to unthread
them. As you might expect, the next 8 foot length of pipe split
LENGTHWISE more than half way down the pipe.

After all this, it was obvious a repair was out of the question. There
was only a few feet of original pipe left, so I just replaced all the
plumbing. Thankfully, I was able to remove the last segment of
galvanized pipe at the shut off valve where the incoming supply comes
through the basement wall.

I installed a new kitchen sink so I could use a standard deck mount
kitchen faucet, then replumbed the entire house using CPVC.

As a bonus, we discovered why the bathtub had no hot water. The
galvanized pipe had completely clogged up with rust and corrosion to the
point that only a few drips of water could flow through.

It's a zoo in the basement.

Yep, sounds like my in-laws place. Old rusty galvanized pipes hanging
down from the floor joists, and big cast iron drain pipes sticking down
that we were always banging our heads on. (Not the mention the scary
looking, cob web covered, knob and tub wiring with missing insulation).

It has taken us a few years, but we replaced the supply lines with CPVC,
and cut out the cast iron drains and replumbed with PVC when we remodeled
the bathroom. I also installed a new breaker panel and underground
service when I rewired the entire house a couple of years ago.

What started out as a few "maintenance" items to help out my in-laws, has
turned into an ongoing project that has already lasted several years. Now
my mother-in-law keeps asking when we're going to remodel her kitchen.
Sheesh...

Anthony