I know it has something to do with the capacitor and a less than 180 degree phase shift. But thats all I know.
Single Phase Motor Reversing
To reverse rotation of a single phase motor,interchange connection of the starting winding. The starting winding is one with a terminal connected to a start capacitor.Disconnect the other end that normally is connected to the running winding or common.Transfer connection of this terminal to the capacitor and the original terminal connected to the capacitor connect to the common winding.