Yamaha Outboard Motors Factory Service Manual F6 and F8, Page 476Get this manual
STARTER MOTOR (F8CW) 3Check: Commutator under cut Clogdirty Clean
Remove all particle metal by compressed air
4Check: Armature coil continuity Out of specification ReplaceArmature coil continuity:
Commutator segments SegmentLaminations SegmentShaft Continuity No continuity No continuity