ELECTRICAL SYSTEM
SYSTEMS OPERATION
TM 5-3805-263-14&P-2
The field winding (1) is a stationary coil assembly
that provides the magnetic field.
The rotor provides the north and south poles
which cut the magnetic field between the stationary
field winding and the stator (2). North and south
poles arc separated magnetically by a non-magnetic
ring (5).
STARTING SYSTEM COMPONENTS
Starter Motor
The starter motor is used to turn the engine fly-
wheel fast enough to get the engine to start running.
The starter motor has a solenoid. When the start
switch is activated, the solenoid will move the starter
pinion to engage it with the ring gear on the flywheel
of the engine. The starter pinion will engage with the
ring gear before the electric contacts in the solenoid
close the circuit between the battery and the starter
motor. When the circuit between the battery and the
starter motor is complete, the pinion will turn the
engine flywheel. A clutch gives protection for the
starter motor so that the engine can not turn the
starter motor too fast. When the start switch is re-
leased, the starter pinion will move away from the
ring gear.
Solenoid
A solenoid is a magnetic switch that does two basic
operations:
a. Closes the high current starter motor circuit
with a low current start switch circuit.
b. Engages the starter motor pinion with the ring
gear.
The solenoid switch is made of an electromagnet
(one or two sets of windings) around a hollow cy-
linder. There is a plunger (core) with a spring load
inside the cylinder that can move forward and back-
ward. When the start switch is closed and electricity
is sent through the windings, a magnetic field is made
that pulls the plunger forward in the cylinder. This
moves the shift lever (connected to the rear of the
plunger) to engage the pinion drive gear with the ring
gear. The front end of the plunger then makes con-
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