TM 5-3805-258-24-1
OPERATOR’S STATION
SYSTEMS OPERATION
INDIVIDUAL CIRCUIT DESCRIPTION
ENGINE STOP SYSTEM
When the key switch is put in the OFF position, a ground is made through the
key switch to activate the 3T689 Stop Relay. Power is sent to the coil of the stop
relay from the output of the main power relay.
When the stop relay is activated, it sends current to the stop solenoid
connected to the rack. When current is sent to the stop solenoid, it is activated
and moves the rack so that no fuel is sent to the engine.
With the ON-OFF-START switch in the OFF position, the main power
relay is activated from the voltage output of the alternator “R” terminals. As
the engine comes to a stop, the main power relay deactivates (becomes not
activated) after the alternator “R” terminal voltage drops. This causes the
engine stop relay to deactivate. When the shut off solenoid is deactivated,
the rack is moved again, and fuel can be sent to the engine. The total time
delay of the two relays is enough to cause the engine to come to a complete
stop before the shutoff solenoid is deactivated and fuel is sent to the engine
again.
NOTE: If the engine does not come to a complete stop before the shutoff
solenoid is deactivated and fuel is sent to the engine, it is possible for the engine
to startup again. If the engine does startup again, lift up on the governor pedal
to stop the engine.
ENGINE STOP SWITCH
1. Engine stop switch.
ENGINE STOP SOLENOID
2. Engine stop solenoid.
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