Brush Testing
- Connect ohmmeter lead to positive brush holder and other lead to negative brush holder. If continuity exists, brush holder assembly is shorted and must be replaced.
- Check brush length. If less than specification, replace brushes. See BRUSH LENGTH SPECIFICATIONS table. Use brush spring scale to check spring tension. Spring tension is measured at point where spring separates from brush.Tension should be greater than 2 lbs. (0.9 kg). Tension specification for a new spring is 3.1-5.7 lbs. (1.4-2.6 kg). Brushes must move freely in holders.
BRUSH LENGTH SPECIFICATIONS
| Application | Standard In. (mm) | Minimum In. (mm) |
|---|---|---|
| All Models | .67 (17.0) | .45 (11.5) |