18:14. Check of brushes and brush holder

1. An ohmmeter check conductivity between each isolated brush and a plate. With conductivity, replace the brush holder.
2. Measure by spring scales or a steelyard effort of a spring.

Effort of a spring: 8,8 N
3. If the effort of a spring is not enough, replace a brush.
4. If the brush is worn-out to the designated limit, replace it.

Brush length:
Nominal: 17 mm
Maximum permissible: 11,5 mm