I have a postwar 275-watt ZW purchased from an estate sale and noticed that the A throttle is not giving any power. Looking under the hood, the roller does need to be replaced but it is not down to the bare nub like some of the other rollers on the opposite end...yet those throttles produce the correct voltage.
The "A" wire from the post seems well connected to the post and to the point where it is soldiered to the throttle gadgetry.
Also, the plug does get warm after only having it plugged in for a few minutes and the prongs are hot to the touch. While I have not noticed any cracks in the cord, I assume the plug needs to be replaced?