Evinrude 4906B 4HP 1969 Owner's Manual page 225

6-36 ELECTRICAL
or the meter indicates continuity, the arma-
ture is grounded and MUST be replaced.
Checking the Commutator
7- Check between
as shown in the accompanying
The test light should light, or the meter
should indicate continuity.
tor falls the test, the armature
replaced.
Turning the Commutator
8- True the commutator,
a lathe. NEVER undercut the mica because
the brushes are harder than the insulation.
Undercut the insulation
mutator bars 1/32" to the full width of the
insulation and flat at the bottom.
ular groove is not satisfactory.
under-cutting work is completed,
the slots carefully to remove dirt and cop-
per dust. Sand the commutator
No. 00 sandpaper to remove any burrs left
from the undercutting.
a second time on the growler for possible
short circuits.
Positive Brushes
9- The positive
identified as the brush with the lead con-
nected to the field coil.
Obtain an ohmmeter.
of the meter to the end of the brush and the
other lead to the terminal.
MUST indicate continuity
brush and the terminal.
cates any resistance,
brush and the lead to the positive terminal
AC MILLIAMMETER
Bar
or check bar-to-bar
illustration.
If the commuta-
MUST be
if necessary, in
between the com-
A triang-
After the
clean out
lightly with
Check the armature
brushes can always be
Connect one lead
The ohmmeter
between the
If the meter indi-
check the lead to the
CORRECT
Negative Brush
10- The negative
identified because the lead is connected
the starter motor end cap.
meter. Make contact with one lead on the
negative brush and make contact
other lead on the starter
meter does not indicate
brush or brush retainer
the end cap.
Positive Brush Installation
11- First, cut the old field coil brush
free. Next, attach
brush to the stiff wire lead on the field coil.
Wrap a fine piece of copper wire around the
lead and the stiff wire from the coil to hold
the brush lead in place while it is soldered.
If the wrapped wire becomes soldered also,
it
no problem leave
become soldered, pull it free after the sold-
er ing is complete.
Use rosin flux and solder the leads to the
SIDES of the wire to prevent
BACK
excess solder from rubbing against the arm-
ature. Be sure the leads are in the right
brush can always be
Obtain an ohm-
with the
end cap. If the
continuity, the
is not grounded to
the lead of the new
in place. If it did not
any
to