# Compressor not restarting. Capacitor issues?



## 3ntropy (Oct 31, 2021)

I've poured over other threads trying to piece together information but can't find anything that specifically addresses my issue. I understand basic principles but please note that I am not an electrician. Please forgive any ignorance on my part.

I have a few question to identify an issue I'm having with an older (20ish years) Craftsman compressor. It runs great on initial start up however it has issues on restart under pressure. The motor attempts to restart and then trips the breaker. I have checked the unloader valve and check valve, both seem to be working fine. I also have removed/checked both the running and starting capacitors. Both measure within the stated uF. However both are measuring on the low end of the range:

Start capacitor (165V)
stated capacitance: 400-480uF
measured capacitance: 416uF

Run capacitor (370V)
stated capacitance: 36-44uF
measured capacitance: 37.6uF

I am assuming this issue would be directly related to the start capacitor and not necessarily the run capacitor, could the start capacitor still be an issue?

Also the run capacitor has three wires coming off which I haven't seen before. Two wires run to other connections which then go the motor and a single wire runs to what I believe is a safety switch in case of mechanical failure of the motor. The other thing is that the wires are integrated into the capacitor; there aren't any spade connections directly on the capacitor (see picture). I can't find this direct replacement capacitor however I would assume there are options out there right?

Thanks in advance for the help!


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## iowagold (Jan 22, 2020)

inside the motor check the start switch.
those fail a lot.


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## 3ntropy (Oct 31, 2021)

Is the start switch inside the motor also known as the centrifugal switch which opens the start capacitor circuit once the motor is spinning?

That would make sense if the run capacitor circuit was open due to a faulty switch then the motor would be attempting to restart without the start capacitor.


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## iowagold (Jan 22, 2020)

yup!


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