Evinrude 4906B 4HP 1969, Owner'S Manual

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6-20 ELECTRICAL
CORRECT
INCORRECT
Armature segments properly cleaned (left) and im-
properly cleaned (right).
the turn the upper cap on the shaft with the
other hand. The cap and shaft should turn
freely with no sign of binding. If either of
these tests are not successful, the bear ing
MUST be replaced.
• Check the amount of brush wear. If the
brush is worn more than 50% of its original
size, or to within 1/4" of the base, it should
be replaced.
Replacement of the brushes is
a simple task. First, remove the brush
retaining screw, and then remove the old
brush and install a new brush. Secure the
new brush in _place with the retaining screw.
If the armature commutator requires
turning, it should be turned in a lathe to
ensure accuracy. The local generator shop
can perform this task, usually for a very
reasonable fee. If the turning is accom-
plished by other than generator shop person-
nel, the following words are necessary. Af-
ter the turning, an undercut should be made.
The insulation between the commutator bars
should be 1-3/4 ", This undercut must be
the full width of the insulation and flat at
the bottom. A triangular groove is NOT
satisfactory. After the undercut work is
completed the slot should be thoroughly
cleaned to remove any foreign material, dirt
or copper dust. Sand the commutator
LIGHTLY with "DO" sandpaper to remove
any slight burrs left from the undercutting.
After all work has been completed, test the
unit again, on the growler.
CD
ASSEMBLING THE GENERA TOR
1- Slide the armature into the frame and
align the top armature cap with the dowel in
the frame. Proper alignment is achieved
when the dowel in the frame indexes into a
matching hole in the cap. As the armature
is moved into place, pull back on the brush-
es, and work them
around the commutator
bar.
2- Install the end cap down over the
studs of the field and armature. Check to
be sure the dowel in the frame has indexed
with the hole in the cap.
3- Install the two thru-bolts and secure
the complete assembly with the nuts.
4- Place the two bushings over the ter-
minal studs of the armature and field. Se-
cure the bushings in place with the washers
and proper nuts (one terminal
is larger than
the other).