electrical contact and complete the batteries-to-starting motor circuit. The contacts and terminals on the magnetic switch
are capable of handling the large current which flows to the starting motor during starting. The return spring pushes the
plunger and contact disk up to the initial position when the coil is de-energized.
b. Removal. Refer to paragraph 99a.
c. Disassembly (fig. 91). Take out the three cover screws (12) with the rubber washers (13), and remove the cover
(11) and the cover gasket (10). Lift out the slotted spring retainer washer (9), contact spring (8), spring retainer washer
(7), and contact disk (6). Lift out the plunger (5). Disconnect the coil leads from the terminal cap assembly (3). Lift off the
terminal cap assembly and the terminal cap gasket (2). Remove the return spring (4) from the case and coil assembly (1).
Unscrew the two terminal studs (16), and remove the lockwashers (15) and plain washers (14). Unscrew the two terminal
nuts (19), and remove the lockwashers (18) and plain washers (17).
d. Inspection and Cleaning. Wipe the switch parts with a clean cloth slightly moistened with carbon tetrachloride.
After cleaning, blow the case and coil assembly and the terminal cap assembly dry with compressed air. Do not soak the
gaskets. Connect a variable resistance, a 24-volt battery, and an ammeter in series with the two coil leads. Adjust the
voltage to 24-volts and read the ammeter. Replace the case and coil assembly if the current is not between 3.1 and 3.5
amperes. Inspect the switch parts for cracks, or corroded surfaces. Flex the springs to detect hidden cracks. Replace
the gaskets and washers if they are cracked, or oil-soaked. Clean a corroded plunger or core surface with fine sandpaper.
e. Reassembly (fig. 91). Place the lockwashers (15) and plain washers (14) on the terminal studs (16), and screw
the studs into the terminal cap assembly (3). Attach the plain washers (17), lockwashers (18), and terminal nuts (19).
Place the return spring (4) over the spindle inside the case and coil assembly (1). Place the plunger (5) over the return
spring. Place the terminal cap gasket (2) on the case and coil -assembly and set the terminal cap assembly on the gasket.
Connect the coil leads. Set the contact disk (6) over the plunger; and install the spring retainer washer (7), contact spring
(8), and slotted spring retainer washer (9). Be sure the washers are cupped around the spring. Place the cover gasket
(10) over the terminal cap assembly. Press the cover (11) over the gasket, and while holding it down, install the rubber
washers (13) and the cover screws (12).
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