Hi
Do you mean stator or rotor, the stator is the bit that doesn't move.
Cracking in a resin mix is normaly down to lack of attention in the resin to catalyst mix, too much catalyst causes the cure to be too fast and the heat generated runs away and the mix goes exothermic, producing even more heat. The resin gives the stator, mechanical stability, if it impregnates the winding properly it will stop them vibrating and breaking the insulation down.
I don't see chipping it off as an option, if the cracking is too bad from comments others have posted on here it looks like a complete rebuild...
Brian