- condition, degree of wear, fit of the brushes to the rings and the pressing force of the springs;
- appearance of slip rings. The slip rings can only be cleaned with a clean rag soaked in petrol or trichlorethylene. Clean slip rings only with fine-grained abrasive paper. It is forbidden to use emery cloth for this purpose;
- bearing condition. They do not require maintenance, as they have a long-life lubrication;
- appearance of the rotor and stator. Make sure that their windings do not have any breaks or burn marks.
Note. In no case should the electrical characteristics of the generator be checked in a circuit with a voltage of more than 14 V. Otherwise, some elements of the generator may fail.
Rectifier diodes are temperature sensitive. Therefore, when replacing them, solder as soon as possible using tongs with sponges. It is not recommended to use an electric soldering iron, since if its insulation is damaged, a short circuit may occur in the rectifier diodes.
It is recommended to clean the generator parts with white spirit; after cleaning, immediately dry the parts, especially the windings, with compressed air.