Westerbeke 6.5 MCG Service Manual page 53

STARTER MOTOR SERVICE
COMMUTATOR AND MICA
1. Check the contact face of the commutator for wear, and
grind the commutator with emery paper if it is slightly
worn.
2. Measure the commutator O.D. with an outside
micrometer at several points.
3. If the minimum O.D. is less than the allowable limit,
replace the armature.
4. If the difference of the O.D. exceeds the allowable limit,
correct the commutator on a lathe to the factory
specifications.
5. Measure the mica undercut.
6. If the undercut is less than the allowable limit, correct it
with a saw blade and chamfer the segment edges.
COMMUTATOR 0.0. • 32MM (1.259aiN)
LIMIT • 31.4MM (1.23621N)
MICA UNDERCUT· 0.50 • O.BOMM (0.0197 • 0.03151N)
LIMIT·
0.2D~M
(0.00791N)
SEGMENT~DEPTH
DF MICA
~~~
~ ~MICA
...
CHECKING MICA
51
A
CAUTION:
Before installing, thoroughly clean the
starter flange and mounling surfaces, remove all old
. paint and rust. Starter performance largely depends on
the quality of the wiring. Use wire of sufficient size and
grade between the battery and starter and fully tighten
to the terminal.