Vintage 3/4 HP Single Phase Peerless Motor Start Capacitor Problem

[Maui]

I have a very old Peerless capacitor start single phase motor that runs on 110V power. It is from the 1920s or 30s and it does run. It spins up to speed with no problem. The issue I am having is that the capacitor is not taken out of the circuit after the motor spins up to speed, and it gets VERY hot very quickly. Any idea of what to check that might be causing this? Could it be the centrifugal switch is not working properly?

Maui

 

[exmaxima1]

You answered your question.

 

[californiaHank]

The electrolytic capacitors used for motor starting have a finite life - over time the electrolyte inside them breaks down and/or dissipates. If the cap in your motor is original equipment, it's well beyond its expected life. Overheating can be one symptom of age. If the motor starts slowly, even if it starts, I'd suspect that the cap needs replacing. If you're sure that it doesn't get switched out of the circuit after starting - verified with a meter - then you're probably right, it's the centrifugal switch. But it's real common to see caps failing (losing capacity) with age, and real old ones can sometimes catch fire or even explode as they finally die.