the "crack" is an air gap, its a designed break,
from the 6 protusions on the core, my first though would be that its a 3 phase syncronous motor :/ however i also feel i am very wrong,
what i feel i could be more right on is that it acts similar to a stepper motor, like most automotive clocks, where your outer winding would actually be 3 offset winding wound in opposite directions, (for north and south for each AC cycle) to bring mains down to 10 RPM (6 poles) and once again i may be wrong here,
and yes hero is correct, motors torque is a function of current per turn, so using an inverse ratio of wire size to turns, should allow you to scale to what ever voltage you please, being aware the wattege will remain the same, so for 24V in place of 240, your looking at 10 times the current,