A start winding motor has either an internal centrifugal switch or a current sensor in the start winding lead to detect when in run, in order to switch it out.
In the PSC motor 'Permanent start cap' the cap is in circuit at all times.
Larger motors have both.
Max.

 

Max, thanks for all your help, got a 10uf run capacitor and its working brilliantly now. Thanks for the advice and patience.