TM-9-2350-277-34 Direct and General Maintenance Manual M113A3 M577A3 M1064A3 M1068A3 M58 Download
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TM 9-2350-277-34 THEORY OF OPERATION — Continued 0003 00 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. HYDRAULIC POWER UNIT The ramp is raised or lowered by an hydraulic system which consists of a pump, a dual-acting cylinder, a solenoid valve, and a fluid reservoir. This system is controlled by a three position switch located near the driver. Moving the valve to either RAISE or LOWER position directs fluid to the appropriate port on the hydraulic cylinder. FIRE EXTINGUISHER SYSTEM The fire extinguisher system will detect and put out fires in the carrier. It consists of two CO2 (Carbon Dioxide) cylinders. Carbon Dioxide can put out fires quickly and effectively. The cylinders are operated manually by pulling cables located on the hull. There is a fire extinguisher located in the driver’s compartment that is manually discharged. This cylinder discharges into the engine compartment. The other is located in the personnel department. SUSPENSION SYSTEM The suspension system supports the carrier and delivers engine power to the road. It allows the carrier to maneuver and be stable. Suspension system parts are the drive sprockets, tracks, idler wheels, track adjuster, road wheels, and road wheel support arms. Also, there are torsion bars and shock absorbers. The drive sprockets drive the tracks. They are powered by left and right final drives from the transmission. The tracks consist of two flexible chains of track shoes. The tracks ride on the drive sprockets and are guided by idler wheels. The idler wheels can be adjusted to maintain correct track tension. There are five pairs of road wheels per side. Track centerguides fit between each pair of road wheels. All road wheels are connected to support arms. ELECTRICAL SYSTEM The electrical system provides power for the carrier. The system operates on wet cell batteries and includes charging, regulating and monitoring equipment. The batteries provide a normal operating 24 volts with an amperage capability of 200 amps per hour. The batteries supply the carrier with electricity when the engine is off. All electrical power is delivered through the distribution box except for the engine coolant heater and personnel heater which are directly powered from the batteries. Electrical power flows from the batteries through the distribution box, cables, and wiring assemblies to the hull. The hull is a ground for the electrical system. The dc generator recharges the batteries and supplies electricity while the engine is running. The dc generator has 200 amps per hour capability. There are several electrical subsystems within the hull. Each subsystem contains at least one wiring assembly. Major electrical subsystems and assemblies include the interior and exterior lights, fuel supply, starting and charging systems, ventilation, heating, and bilge pumps. 0003 00-3 Change 2