COMPENSATOR 2849552 - Caterpillar

Shutoffs
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 critical levels for the following items: operating temperature, operating pressure, operating coolant level and operating speed (rpm). 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 engineAir 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 cause of the shutoff should be determined 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.Overspeed Shutoffs
Illustration 1 g00293335
(1) Magnetic pickup
(2) Flywheel housing The magnetic pickup senses the passage of the teeth that are on the flywheel ring gear. The Electronic Overspeed Switch is set at 118 percent of the rated engine speed. If the engine speed increases above the overspeed setting, the magnetic pickup will sense the overspeed. A signal is sent to the Electronic Overspeed Switch. The Electronic Overspeed Switch activates both the air shutoff solenoid (if equipped) and the fuel shutoff solenoid.The shutoffs must be reset before the engine will restart. The air shutoff lever that is located at the top of the air inlet housing must be manually reset. The cause of the overspeed must be determined before the engine is restarted.Alarms
Alarms consist of a switch and a contactor. The switches are wired to the contactors. The contactors activate alarm circuits in an annunciator panel. Your engine may be equipped with the following switches:Engine oil pressure - The engine oil pressure switch indicates when oil pressure drops below rated system pressure.Coolant level - The low coolant level switch indicates when the coolant level is low.Coolant temperature - The coolant temperature switch indicates high jacket water coolant temperature.Note: The sensing element of the coolant temperature switch must be submerged in coolant in order to operate.Engines may be equipped with alarms in order to alert the operator when undesirable operating conditions occur.
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. The alarm will continue until the condition is corrected. The