Checking Carbon Brushes and Commutator

1. Undo cover strap of generator.
2. Check carbon brushes for wear and free travel in the brush holder guides. Brushes which completely disappear into the brush holder are worn and must be replaced; the same applied to brushes which have become heavily oiled.
3. If the commutator is oily or greasy it can be cleaned with a clean cloth which has been soaked in petrol and wrapped round a piece of wood, When doing this care should be taken to ensure that no dirt gets into the ball bearing.
4. Check the pressure springs for tension (see electrical data) if necessary. replace defective springs.
5. If the commutator surface has become uneven as a result of running in of the brushes or has burn spots, it should be skimmed.

Note