2008 Polaris ATV Predator 50, Sportsman Outlaw 90 Service Manual, Page 166Get this manual
ELECTRICAL 2Remove the three screws and washers2Remove the brush plate and brushesMeasure the brush length and replace if worn past the service limit
Remove magnet housing while holding the armature and brush holder section together
Brush Length Service Limit 0.20" (5 mm)
34Inspect the surface of the commutator for wear or discolorationSee Armature TestBe sure that the terminal bolt insulation washer is properly seated in the housing and the tab on the brush plate engages the notch in the brush plate housing