(Another) Jim wrote...
This is exactly what a capacitor run pony motor would do.
See if any capacitors are hidden away.

*click* -- sound of a light bulb turning on

I thought a cap run motor had two caps. This one has only one. I think
its a permanent-split-capacitor motor.

But your point is well made. The PSC-type motors always keep the
start/run capacitor in the start winding circuit. It never drops out. So,
in that regard, the start winding of a PSC motor is just like the run
winding of a cap run motor, except for the significantly higher winding
resistance.

Wonder what will happen if I also remove the pony motor capacitor from
the start winding circuit when the contactor opens... We'll find out.
Wish I'd used a three-pole contactor for that pony motor, now. :-)

I *still* can't figure out why the thing gets hot, though, with
essentially no load.

Thanks!

Jim