PULLER G 6V4061 - Caterpillar

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(14) Case drain filters (15) Hydraulic tank (17) Small steering piston pump (19) Large steering piston pump (21) Pump drive
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(15) Hydraulic tank (17) Small steering piston pump (19) Large steering piston pump (21) Pump drive
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(14) Case drain filters (15) Hydraulic tankSmall steering piston pump (17) and large steering piston pump (19) are pressure compensated piston type pumps. The steering piston pumps, the fan drive pump, the brake actuation and rear axle motor drive, the hoist and brake cooling gear pump, and the brake cooling motor drive are driven by pump drive (21). Pump drive (21) is on the right hand frame rail near the rear of the flywheel housing. Pump drive (21) is driven by a drive shaft. The drive shaft is connected between the pump drive and the engine. The steering piston pumps (17) and (19) operate only when the engine is running.The maximum outlet pressure of the steering piston pumps is controlled by accumulator charging valve (2). The cut out valve in accumulator charging valve (2) will signal pressure compensator valve (18) to destroke the steering piston pumps when the steering accumulators are full.Pressure and flow compensator valves (18) and (20) are fastened to steering piston pumps (17) and (19). Pressure and flow compensator valves (18) and (20) determine the swashplate angle of the steering piston pumps. The high pressure cutoff valve in pressure and flow compensator valves (18) and (20) is set at a higher pressure than the cut out valve in accumulator charging valve (2). If the steering accumulators are full and accumulator charging valve (2) does not send a signal, the high pressure cutoff valve in pressure and flow compensator valves (18) and (20) will destroke the steering piston pump.The low pressure standby pressure of the steering piston pumps is controlled by the flow compensator valve in pressure and flow compensator valves (18) and (20). The flow compensator valve in pressure and flow compensator valves (18) and (20) will upstroke the pumps in order to maintain minimum pressure in the circuit.
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(15) Hydraulic tank (23) Fill port for the steering system (24) Location of steering oil temperature sensorInternal leakage from steering piston pumps (17) and (19) is returned to hydraulic tank (15) through case drain filters (14). On machines 5YW201-229, case drain filters (14) are bolted to the back of hydraulic tank (15). On machines 5YW230-UP, case drain filters (14) are located between hydraulic tank (15) and the front brake oil coolers. Return oil from the steering system flows through steering filter (10). Steering filter (10) is located between the steering solenoid and relief valve (6) and the hydraulic oil cooler (11). Normally, oil flows through these filters and clean oil is returned to hydraulic tank (15). Any debris in the oil is stopped by case drain filters (14) and the steering filter (10) .If any filter element becomes full of debris, the restriction to flow causes a pressure increase. Each of the filters has a bypass valve. The bypass