American Standard Diverter Stem Stuck
I have a circa 1965 AS Heritage in the wall 3-handle tub/shower fixture. I believe it's a Hertitage Model "N 1012" or N 1020". The diverter works spoaratically - the water flows to the shower, but then abruptly stops. With the diverter arrow pointing down for the tub water flows just fine. The diverter knob to the shower only points to 10 o'clock. That's as far as it'll turn.
I've removed the shower head. I've removed all the diverter chrome parts. I removed the outer collar and large retaining nut. Flooded the stem with white vinegar to remove the calcium crud. I can't, for the life of me, pull the stem out to fix/replace the part. Since I don't have proper instructions, I don't want to just yank it out, and it doesn't seem to screw out.
Please help me to remove the diverter stem.