My shower diverter quit working this morning. (I gave it the tiniest bit of additional torque this morning and now it is diverting only a trickle.) It is the middle knob variety and is probably a Stirling. The diverter assembly hasn’t been touched since I bought the house in 1989.
The screw came out just fine, but the knob, which should slide off, won’t budge. A friend suggested that corrosion is holding it on and that a few whacks with a hammer will loosen it up. Before I make matters worse, any ideas?