Honda BF35A-BF45A Outboard Motors Shop Manual., Page 245Get this manual
bINSPECTION BRUSH LENGTH
Measure the brush lengthIf brush length is less than standard, replace the brush holderSTANDARD
SERVICE LIMIT
9.8 (0.39 in)
BRUSH INSULATION
Check for continuity between the brushesThere should be no continuity
MICA DEPTH
If the grooves are clogged or mica depth is less than the service limit, recut the grooves using hacksaw blade or small file