Not holding air. Darn. How hard do I need to torque that retaining nut? I felt like it started OK but after about 3 full turns got pretty hard, and I was concerned about cross-threading. Also wondering about that check valve that I creased with the compression tube or the neoprene vs. lead washer. The air is just blowing through, which would suggest the rearward seals. I'm remembering that old saying, "If it ain't broke..."
You might have lead in the threading. Clean it out use a hard bristle toot brush or brass brush.