TM-9-2350-311-34-2 Maintenance Manual for Volume 2 M109 Cab Download
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TM 9-2350-311-34-2 1-14.7 Location and Description of Manual Pump Accumulator Assembly Manual pump accumulator assembly (1) is mounted at the right front side of the trunnion bracket above the manual elevat- ing hand pump. It maintains a minimum pressure on hydraulic fluid in the manual elevating hydraulic system. It assures an immediate response in the manual system when sudden demands for quantities of hydraulic fluid cause excessive pres- sure drops. The manual pump accumulator assembly consists of a cylinder (2) housing a floating piston. The top end of this cylinder contains a gas valve (3), while the bottom end has a threaded linear cap (4). The top of the cylinder is precharged with dry nitrogen under pressure. This pressure is applied against hydraulic fluid at the bottom of the cylinder. Dry nitrogen and hydraulic fluid are separated by a floating piston. The manual elevating hydraulic system is charged by turning the manual elevating hand pump handle counterclockwise until initial movement of the elevating mechanism is detected. This will charge the manual pump accumulator assembly with hydraulic fluid under pressure. An accumulator cap (5) covers a gas valve. 1-25