My house was built around 1983. The original silcock was pretty well mudded over with mortar. When it leaked, they pulled the guts out and welded some adapters and tubing onto it and just screwed another silcock on. Guess they did not want to chip away the mortar. Well, the weld cracked and the monstrosity leaked. Tried some JB water-weld and it slowed it it down, but I know that is not a permanent fix. I tried to see what I had from the crawl space, but because of the new AC venting, there is just no way I can work on it from inside. There is no separate shutoff for the silcock
I carefully chipped some mortar away and exposed some pipe. It took forever because I did not want to bust the pipe.
Can anyone please look at the attached pictures and tell me if it is a threaded adapter or if the silcock was sweated on. This has been a real pain and I don't want to just start to torque on a pipe and and then have a real problem.
Maybe its wishful thinking, but I swear I think I see some plumbers dope there!
Thanks so much for your help.

 

With my eyes I'd say sweated on. Before you do anything put in an isolation valve inside the house. Put it as close to the hose bib as possible, but even if it's 10 feet away as long as the hose bib pipe can be turned off from inside. Use Sharkbites, they're easy. Then you can spend time and cut that sucker out from any place after the Sharkbite valve. You can slide another piece of copper through the hole and then attach a Sharkbite or thread hose bib to the end of it.

 

I'm 98% sure that is a female threaded sillcock and the copper has a male threaded adapter soldered on it. Try to get an adjustable wrench on the hex of the thread adapter and hold it fast while twisting off the valve.

Also, follow Norm's advice about FIRST installing an inside shut-off valve before working on the outside.

 

Thanks for the advice, I really appreciate it.
I hate to second guess myself on this stuff because I know how fast it can spiral down hill!
Sounds like a good idea to use shark bites for the isolation valve. Thanks Norm! Furd, I'm with you on the threaded adapter into the silcock.
Glad to have you people as a resource.
Thank you!

 

Happy ending...it was threaded!
Thanks again!