AC motors and carbon brushes
FLYWELDER: I am a mechanical engineer who has had a little expierience with electric motor brushes. If you cannot find the exact brush, or even if you do, yuou will have to "mate" it to the commutator. You do this by wrapping a piece of fine emery paper, with the abrasive side out, around the commutator and installing the brush. Then move the emery paper and or brush back and forth until it the same contour as the commutator. Another problem is that commutator may require machiing to true up the surface. If you a near an electric motor dealer, they may be able to do this. Even with perfect brushes and seating some sparking (minor) will occur.