TM-9-2350-261-20-1 Unit Maintenance Manual Volume 1 M113A2 M577A2 M1064 M1068 M1059 M901A1 Download
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TM 9-2350-261-20-1 THEORY OF OPERATION — Continued 0003 00 AUXILIARY AUTOMOTIVE SYSTEM The auxiliary automotive system includes driver controls, personnel heater, bilge pumps, crew ventilation system, and fire suppression system. Driver Controls The driver controls regulate the engine, transmission, and steering braking systems of the carrier. The fuel shutoff control is used to stop the supply of fuel to the engine injectors. To start the engine, the driver must push in the fuel shutoff control. The throttle linkages are used to control the engine speed. The gear selector allows the driver to choose the proper gear for the carrier. The steering and braking levers control separate right and left steering brakes in the control differential. By pulling on the levers, you can slow or stop either track for steering, or both tracks at once for stopping. A lock button at the top of each lever lets you set and lock the brakes for parking. Pivot Steering And Brakes Pivot steer brakes are disk brakes and work like the differential brakes, but quicker. Personnel Heater NOTE New style heater MODEL A-20 needs to have the power cable removed before any welding is performed on the hull. If left connected, a circuit card in the heater will be damaged by MIG or TIG welding. The personnel heater system provides heat inside the carrier. Major parts are the combination combustion chamber/heat exchanger, blowers, a fuel pump, fuel filter, and an electrical control. The heater operates using diesel fuel pumped from the fuel tanks. Fuel goes through fuel filter and is then delivered to the combustion chamber from the fuel pump. Outside air is drawn into the combustion chamber by one of the blowers. A blower draws air from the crew compartment into the heater exchanger. The air is warmed by heat created by the combustion process and then returned to the crew compartment. Bilge Pumps Two electrically-driven bilge pumps remove water and other liquids from the hull. Water enters the pumps through a screened inlet. The pumps force water out of the carrier through outlet tubes. The bilge pumps are controlled by a switch on the driver’s instrument panel. Fire Extinguisher System The fire extinguisher system consists of two CO2 (carbon dioxide) cylinders, one fixed and one portable. Carbon dioxide puts out fires quickly and effectively. The fixed cylinder is located near the driver’s compartment and is operated manually by pulling cables located on top of carrier next to driver’s hatch. The fixed cylinder releases CO2 in the power plant compartment only. The portable fire extinguisher is located in the crew compartment and is manually discharged. HYDRAULIC SYSTEM The ramp is raised or lowered by a hydraulic system which consists of a pump, a cylinder, a control valve, and a hydraulic tank. This system is controlled by a three-position valve located near the driver. Moving the valve to the RAISE position directs fluid to the ramp cylinder. Moving the valve to the LOWER position allows the gravity of the ramp to return hydraulic fluid to the reservoir. There is a breather hose on the ramp cylinder to allow the cylinder to breathe air. The hose is connected to the rear bilge pump tube outlet to prevent water in the lower hull from getting into the ramp cylinder and causing it to corrode. 0003 00-3