Hi, I have an old tub from 1972. I saw that tub drains unscrew, so I tried it. Didn't work, so before I try harder and break it, are they supposed unscrew on all tubs, especially old ones? I know it is rusty and probably stuck from years of being in there, but I wanted to be sure it is supposed to come out. Assuming it does come out, do you think a newer drain will fit? Use wd40 to loosen it if it comes out? Edit: Could I break the tub somehow if that drain is supposed to come out or can I break things trying to? This is what I have:

I have several Champion-Arrowhead 469 12QTLF Arrow-Breaker bibs on the house. I always disconnect the garden hose in the fall before freezing weather. Today, I connected the hose to one and turned it on to spray my deck. The pressure was very low at the sprayer so I shut the sprayer off, but still heard water running. So I turned the hose bib off and went inside to find water had pooled inside the house on the floor where the hose bib penetrated the wall. I've replaced a check assembly on one before, but that was because the bib was leaking outside, not inside. Any idea what could have caused this? What action do you recommend I take? Thanks.