Replacing Valve seat

I have an on-off valve (like for a hose) just after my main incoming water valve that is leaking. I am trying to replace the seat, but can't seem to get the stem out. I undid the nut holding it on, and unscrewed the valve as far as it will go.

Do I keep unscrewing the valve with force? (I tried to with channel locks but was afraid I might break more than just that valve)

Or do I just tap it out with a hammer? (I tried this too, but was again afraid of breaking more than just the valve)

The house was built in 1975 and I'm sure it's original. It's threaded, but the pipe (1/2") is inserted INSIDE of the threaded section and soldered (is this common practice? I replace my two washer/dryer valves and they were this way as well).

1st If are you talking about a gate valve if so do not unscrew with force or you could drop a gate And wont be able to get any water. You have to unscrew the whole top of the valve off, And pull the guts out and hopefully you can find a match that will fit in the Body. The soldering tells me that was a quick fix to a water leak around the threads. If nothing else works Buy you 2 compression coupling (If threads not available to use on pipe) Cut out the old pipe use pvc Schedule 40 and Get you a Ball Valve (glue in) Use your comp coupl attach pvc with glue bvalv to old pipe. And Tighten the couplings

Don't use PVC for inside water, CPVCfor inside water lines. Stick with copper/ brass valve, if possible. Once a shut off valve gets too bad replacement is usually the best option. If you can get it apart you need a new packing seal and washer.

Haha...thanks, guys. I've actually been over there all day (bought the house and am fixing it up before moving in). The solder is NOT a quick fix for leaking threads...the threads are NOT used. It's a 3/4 (or 5/8) threaded fitting with a 1/2" copper that goes INSIDE of it.

ANYWAY...I figured by the time I got a dollar washer, and another couple dollars for the "packing seal", it's easier to get a 5 dollar new valve. (I got a 1/2" compression valve. (It comes off of a "T" just after the main shutoff) When I did cut the old valve off it had some nasty nasty white calcium looking buildup inside.

But back to my original question...once you unscrew the nut holding the "gate" on, do you just tap the valve out or do you forcably (I picked up a no on this) try to keep "opening" the valve?

valve

You were probably not loosening the correct point. With most of them the packing nut is just to stop leaks at the handle. You unscrew the top portion from the valve body using the lower hexagonal point. But since most of those faucets do not have seats, and some do not even have screws to hold the washer, replacing the valve, or at least the operating portion, is the most common repair.