(4) Remove the mounting screws attaching the magnetic switch (4) to the mounting bracket (9). Remove the switch
and the suppression capacitor (8).
c. Installation (fig. 81).
(1) Attach the magnetic switch (4) and suppression capacitor (8) to the mounting bracket (9). Tighten the mounting
screws securely.
(2) Connect the lead (6) with the magnetic switch terminal and tighten the nut (5).
(3) Connect the starting motor cable (20) with the magnetic switch stud. Tighten the stud nut (2).
(4) Remove all protective tape from the battery cable (14). Connect the cable with the magnetic switch stud and
install the lockwasher (7) and nut (2). Tighten the nut securely.
(5) With the ignition switch on, push the starter button and check the magnetic switch for proper operation.
116. Magneto
a. Description (fig. 33). The magneto is a continuous, heavy-duty, clockwise rotation, radio shielded unit. It is
connected to the governor by the impulse coupling (10) and driven by the governor gear. The entire unit is enclosed in a
grounded metal frame. The end cap (20) has six adapters (1) for the shielded spark plug leads The primary ground
terminal (19) is connected to a shielded cable for operation by the remote control switch. When the breaker points in the
end cap are closed, the revolving magnetic rotor (15) causes an induced current to flow in the primary circuit of the
stationary coil (7). When the breaker points open, the primary current stops instantly and its field collapses immediately,
thus inducing a very high voltage in the secondary winding of the stationary coil. The secondary circuit is completed when
the ignition spark jumps the spark plug point gap to ground. The impulse coupling (10) facilitates starting of the engine by
automatically retarding the ignition spark during the starting operation and at the same time producing an intense, hot
spark which would otherwise be impossible at very low engine speeds. The impulse feature disengages as soon as the
engine develops speed, after which the coupling serves as a conventional drive member.
b. Testing Magneto for Spark (fig. 33).
(1) Tag the spark-plug leads to insure their proper replacement.
(2) Unscrew the spark plug lead adapters (1) on the top of the magneto end cap and pull out the shielded spark-plug
leads.
(3) Use a short piece of stiff, rubber-insulated wire to test the spark. Remove one-half of an inch of insulation from the
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