(4) Remove the retaining ring (38) that
(10) Install the brushes (par. 113) and the
secures the spur gear (39) in the
brush access cover (23).
sleeve bearing (40) and remove the
f. Bench-Testing the Starter.
(1) No-load Test. Connect a 100-ampere
(5) Press the roller bearing (45) and the
ammeter, a carbon-pile rheostat, and
sleeve bearing (40) from the contact
a 6-volt battery in series with the
breaker plate (46) if defective.
starter terminal and housing. con-
(6) Remove the two setscrews (49) that
nect a voltmeter from the terminal to
secure the magneto coil (48) in the
the housing. With the voltage ad-
housing and remove the coil.
justed to 5.0 volts, the current should
be 68 amperes maximum at 4,000 rpm.
(7) Remove the cotter pin (21) and castel-
If the current and speed are both low,
lated hex nut (22) that secure the
check for high resistance in the in-
helical gear (23) and sleeve bushing
ternal connections. If the current is
(24) on the rotor and remove the gear
high and the speed is low, check the
armature for binding.
(8) Using a suitable gear puller, remove
(2) Stall Torque Test. With the starter
the magneto coupling (29) with at-
connected as in (1) above, fasten a
tached spring (26) and housing (25)
torque arm and a spring scale to the
from the rotor.
armature at the drive end. Adjust the
(9) Remove the housing and spring from
rheostat to give 2.0 volts. The correct
the coupling, Remove the spring (30)
current reading is 280 amperes maxi-
from the coupling.
mum and a stall torque of 4.4 ft-lb
Warning: Remove the housing
minimum. Stall torque is the product
from the spring carefully and slowly
of the spring scale reading in pounds,
to prevent the rapid uncoiling of the
multiplied by the length of the torque
arm in feet. If current and torque are
(10) Remove the woodruff key (28), pack-
both low, check the internal connec-
ing retainer (31), flat washer (32),
tions for high resistance and the
preformed packing (33), and flat
brushes for proper contact. High cur-
washer (34) from the rotor.
rent and low torque may be caused by
(11) Remove the retaining ring (35) from
a defective armature or field winding.
the shaft of the rotor and press the
Install the starter (par.
rotor out of the ball bearing (37).
(12) Remove the retaining ring (36) and
185. Ignition Magneto
the ball bearing from the housing.
(13) Remove the threaded straight pin
the magneto (par.
a. Removal. Remove
(27) from the housing.
c. Cleaning, Inspection, and Repair.
(1) Clean all metal parts with an approved
(1) Remove the distributor contact set
cleaning solvent and dry thoroughly.
(2) Test the coil on a coil tester. The pri-
(2) Remove the retaining ring (41, fig.
mary draw must be 1.6 amperes. Re-
21) and the threaded straight pin
place a defective coil.
(43) that secure the spur gear (42)
(3) Test the capacitor on a capacitor tester
to the magneto rotor (47) and re-
for shorts, opens, and leakage and for
move the gear.
capacitance that should test between
(3) Remove the four screws (20) that se-
0.17 and 0.21 p f (microfarad). Re-
cure the contact breaker plate (46) to
place a defective capacitor.
the magneto housing (50) and remove
(4) Inspect the bearings for nicks, burs,
the breaker plate and flat washer
and abrasions. Rotate the ball bear-