INJECTOR GP-FUEL 7E8727 - Caterpillar

Shutoff and Alarm Systems
Shutoffs and alarms are electrically operated or mechanically operated. The operation of all electric shutoffs and alarms utilize components which actuate switches in a sensing unit.Shutoffs are set at more critical levels for the operating temperature, operating pressure, operating coolant level, and operating speed (rpm) than the alarms. The particular shutoff may need to be reset before the engine will start.
Always determine the cause of the engine shutdown. Make necessary repairs before attempting to restart the engine.
Be familiar with the following items:
Types and locations of shutoff
Conditions which cause each shutoff to function
The resetting procedure that is required to restart the engineAlarm switches consist of a sensor and a contactor. Examples of sensors are the magnetic pickup for detecting speed, and the pressure and temperature sensors. Sensors are wired to contactors. The contactors activate alarm circuits in the annunciator panel.Alarm switches are set at less critical levels than the shutoffs. The alarms warn the operator that an unsafe operating condition is occurring. The engine will continue to run when an alarm sounds.When an alarm is activated, corrective measures must be taken before the situation becomes an emergency in order to avoid possible engine damage. If corrective measures are not taken within a reasonable time, engine damage could result. Alternatively, a corresponding shutdown device (if equipped) will stop the engine. The alarm will continue until the condition is corrected or the alarm is reset by the operator.A switch may be installed in the alarm circuit for silencing the alarm while the engine is stopped for repairs. Before starting, be sure that the switch is moved to the closed ON. Be sure that the warning lamps will operate. The engine will not be protected if the switch is left in the open OFF position.
Always determine the cause of the engine shutdown. Make necessary repairs before attempting to restart the engine.
Air Shutoff Solenoid (If Equipped)
This optional solenoid is located on top of the engine. The air shutoff is part of the air inlet system. When the solenoid is activated, the solenoid mechanically shuts off the inlet air to the engine. The solenoid can be activated only by the overspeed switch or by the emergency stop push button (ESPB). The air shutoff must be reset before the engine is restarted.Fuel Shutoff Solenoid
The fuel shutoff solenoid is located on the governor or the fuel shutoff solenoid is located on the fuel injection pump. When the fuel shutoff solenoid is activated, the solenoid moves the fuel rack "OFF". The fuel shutoff solenoid moves the fuel rack directly or the fuel shutoff solenoid moves the fuel rack through the governor.Mechanical Oil Pressure and Water Temperature Shutoff
Illustration 1 g01009004
(1) Water temperature sensing valve
(2) Oil pressure sensing valve
(3) Shutdown cylinder
(4) Shutdown cylinder knob A mechanical shutoff system (if equipped) provides protection for low oil pressure and for high water temperature. The main components are a water temperature sensing valve (1), a oil pressure sensing valve (2), and a shutdown cylinder (3). Pull out the shutdown cylinder