CONTROL AR-AUXILIARY 5166643 - Caterpillar

Fuel/Oil Pressure Switch:
This switch is mounted in the fuel manifold between the clean side of the fuel filter and the fuel injection pump housing. Low fuel pressure (below 3 psi) opens the switch and the electrical circuit to either the shut off solenoid or the circuit between the alternator and the alternator regulator. Opening of these circuits prevents the battery from becoming discharged while the engine is stopped. This switch can also be used with an electric governor. In this application, oil pressure closes the switch to allow the electric governor to control engine speed.
This switch does not require resetting.Mechanical Safety Shutoff Control
The mechanical safety shutoff is both a low oil pressure and an overspeed shutoff device. A high water temperature shutoff can be installed which uses the low oil pressure shutoff device to stop the engine.On 6 cylinder engines, the mechanical shutoff is mounted on the side of the engine. On vee engines, the shutoff is mounted in the vee of the engine between the two banks of cylinders. The high water temperature shutoff is installed in the temperature regulator housing of all engines.If an overspeed, low oil pressure, or high water condition occurs, a spring loaded rod is mechanically tripped internally, which moves and holds the rack in the shutoff position.Difficult starting with long periods of cranking can trip the low oil pressure shutoff. The reset lever must be moved and latched in the run position before starting can be accomplished. Normal stopping of the engine will not trip the shutoff device. The basic cause for the shutdown can be determined by the manner in which the shutoff must be reset:1. Push the reset lever (or handle). If the rod latches, an overspeed condition stopped the engine. Investigate the cause for overspeed condition. If the rod does not latch, the engine was stopped because of a low oil supply to the shutoff control. This could be caused by either low engine oil pressure, or by the high water temperature shutoff bypassing the oil to the mechanical shutoff. Therefore, perform checks for both low oil supply and high water temperature. Reset the control by the following steps:1. Push the reset button firmly. 2. Push the reset lever (or handle) until the rod latches.If the reset lever does not move freely, check the reset cable for kinks, binds, or lack of lubrication. Make needed repairs or adjustments.Air Safety Shutoff Control
The air shutoff control is an attachment to the mechanical safety shutoff device installed on large bore vee type engines. When an emergency condition occurs, the mechanical shutoff pushes the rack into the shutoff position and pulls a butterfly valve, located in each inlet manifold, to the closed position. The air safety shutoff control must be reset before starting. If an overspeed condition shut the engine down:1. Pull the air shutoff reset lever on the air inlet manifold to the RESET position. 2. Release the lever. The lever should move slightly and then latch in the RUN