40-AMPERE CIRCUIT BREAKER

TM 5-2420-222-20-1

ENGINE ELECTRICAL CIRCUITS - CONTINUED

Connected by wire between ac generator output terminal and ignition lock switch BATT terminal.

Protects starting circuit from excess voltage.

STARTER SWITCH

Normally open switch.

Connected by wire between starter neutral safety switch negative terminal and starter solenoid switch positive

terminal.

When pushed with range shift lever in neutral, activates starting circuit which energizes starter solenoid switch to

activate starter motor and crank engine.

STARTER NEUTRAL SAFETY SWITCH

Connected by wire between ignition lock switch IGN terminal and starter switch positive terminal.

Closes to complete starting circuit when range shift lever is in neutral.

Opens to interrupt starting circuit when range shift lever is not in neutral to prevent starting engine when loader

backhoe is in gear.

HYDRAULIC PUMP STROKE CONTROL SOLENOID VALVE

Normally closed solenoid is opened when starter switch is closed to bypass hydraulic pump discharge oil into

pump crankcase during engine cranking.

Reduces load on engine to make starting easier.

ENGINE STARTING AID SOLENOID SWITCH

Connected by wire through positive side of starter switch to ignition lock switch IGN terminal.

Normally open switch.

When pushed to close, activates engine starting aid fluid injection solenoid to inject measured shots of engine

primer fluid into engine air supply for cold weather starts.

ENGINE STARTING AID FLUID INJECTION SOLENOID

Considered part of fuel system.

Holds replaceable cannister of engine primer fluid.

Connected by engine starting aid fluid injection tube to air inlet housing.

Releases measured shots of engine primer fluid for cold weather starts when activated by pushing engine starting

aid solenoid switch.

FUEL SHUTOFF SOLENOID

Normally open solenoid housed in fuel metering pump is considered part of fuel system.

Connected by wire from ignition lock switch IGN terminal through time total meter positive terminal.

Grounded by mounting hardware to engine cylinder block plate.

Closes to allow fuel flow for engine operation when ignition circuit is energized.

Opens to cut off fuel flow when ignition circuit is interrupted, to shut down engine.

Keeps engine from starting when manually cranked if battery ground cable is disconnected.

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