Wiring a Crompton Parkinson single phase motor
One thing I did notice was that with the power on the spindle locked – I couldn’t turn it in either direction until I cut the power.


One possible problem is that the rotor is moving axially. If you removed the rotor, you may have made an error in reassembly. There were probably several washers of different types at each end. In addition, the centrifugal switch must engage with a mechanism on the shaft. There may be something not right about those items either because of a reassembly error or a mechanical failure.

I can't think of a wiring error that would make the shaft lock.