contact is made with the shield around resistor. Be sure to keep the screwdriver at right angles to the
base and hold it firmly in place during the check so that the blade touches the regular base and shield at
the same time. This action temporarily cuts out the voltage regulator unit. With an ammeter connected
between the battery and regulator at operating temperature, operate the generator at 50 percent above
rated output speed and note the current setting.
(b) Jumper lead method. Remove the voltage regulator cover and connect a jumper lead across the voltage
regulator contact points (2). With the generator operating at 50 percent above the rated output speed
and with the regulator at operating temperature, note the current setting.
(c) Battery discharge method. Partly discharge the battery by cranking the engine for 30 seconds with the
ignition turned off. Do not run the starting motor continuously for more than 30 seconds. Immediately
after cranking, start the engine and note the current setting with the generator operating at 50 percent
above the rated output speed.
(d) Load method. If a load approximating the current regulator setting is placed across the battery while the
current regulator is being checked, voltage will not increase sufficiently to cause the voltage regulator to
operate. This load may be provided by a carbon pile or a bank of lights.
f. Polarizing the Generator.
(1) After any tests or regulator adjustments, the generator must be repolarized after the leads are reconnected
but before the engine is started.
(2) Disconnect the lead from the FIELD terminal of the regulator and momentarily touch this lead to the
regulator BATTERY terminal. This allows a momentary surge of current to flow through the generator field
windings which correctly polarizes the generator. Failure to do this may result in severe damage since
reversed generator polarity causes vibration, heavy arcing and burning of the relay contact points.
193. Starting Motor
a. Removal. Refer to paragraph 114b.
b. Disassembly.
(1) Remove the cover band screw (23) and nut (24). Remove the cover band (22).
(2) Remove the through bolts (21) and lockwashers (20).
(3) Pull the commutator end frame (19) away from the starting motor frame (40) slightly.
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