Brush Holder Test
- Using an ohmmeter, check continuity between positive and negative brush holders (brackets). See Fig 1 . Continuity should not exist. If continuity exists, brush holder assembly is shorted and must be replaced.
- Measure brush length. Insert brush into brush holder. Bring brush into contact with commutator and attach a spring scale to spring. Measure brush spring tension at moment spring lifts off brush. See Fig 2 . If brush length or spring tension is less than specification, replace brush holder assembly. See STARTER SPECIFICATIONS . Ensure brushes move freely in holders.
NOTE:
To seat new brushes after installing them in their holders, slip a strip of #500 or #600 sandpaper, with the grit side up, over the commutator, and smoothly rotate the armature. The contact surface of the brushes will be sanded on the same contour as the commutator.