I have a 2 speed Pentair Dynamo pool pump P/N 340221. I discovered today that when I switch over to high speed the motor turns off after 30 seconds or so. After a minute or so it turns back on only to repeat the process. From what I read, it may be that the thermal overload is responsible for shutting it down, but I need to find out why. But, I feel no excessive heat at all. I checked voltage and I have a constant 117 volts at the motor when its running. While its not a typical bad capacitor symptom, could a bad capacitor cause this problem. I know typically a bad capacitor will prevent a motor from starting (giving the hum noise), can a bad capacitor cause a motor to shut down after the motor has started? Just trying to brainstorm without throwing unneeded parts at this thing; my thoughts are that the capacitor is being depleted of energy faster than it can be replenished. Does anybody have any other ideas? Thanks for any input...