KIT-ENGINE OVERHAUL 4363145 - Caterpillar

Hydraulic Pump Flow and Pressure Control System
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Pump compartment (23) idler pump (24) Drive pump (25) Pilot pump (26) Proportional reducing valve (power shift pressure) (50) Delivery line (drive pump) (51) Delivery line (idler pump)This machine is driven and controlled by the following systems:
The main hydraulic system controls the cylinders, the travel motors, and the swing motor.
The pilot hydraulic system supplies oil to the main pumps, the main control valve, the swing brake, the travel motors, and the cooling fan.
The medium pressure hydraulic system supplies oil to the system for rotation.
The electronic control system controls the outputs of the engine and pump.The main hydraulic system delivers oil flow from drive pump (24) and idler pump (23) in order to control the following components: stick cylinder (4), boom cylinders (5), heel cylinder (7), tilt cylinder (8), grapple cylinder (10), left travel motor (33), right travel motor (34) and swing motor (35).
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Main control valve (9) Main relief valve (52) Right control valve body (53) Left control valve bodyDrive pump (24) and idler pump (23) are variable displacement piston pumps. The performance of both pumps is equal.Drive pump (24) is directly connected to the engine by a flexible coupling. The drive pump delivers oil to the right control valve body (52) of the main control valve. Idler pump (23) is mechanically connected to the drive pump through gears. The idler pump delivers oil to the left control valve body (53) of the main control valve. Gear type pilot pump (25) supplies oil to the pilot hydraulic system. Gear type pilot pump (265) is directly connected to drive pump (24) by a coupling. All engine output is used to drive these three pumps.As the load pressure increases during working conditions, the main pumps increase the delivery pressure and the pumps decrease the flow rate. The hydraulic horsepower remains constant even though the delivery pressure and the flow rates change. The hydraulic horsepower is approximately identical to the engine horsepower.When no work is being performed, pump oil flows through main control valve (2) and into hydraulic tank (47). The main control valve sends a negative flow control signal to each main pump regulator in order to destroke the pump to the minimum output flow.If an operation is being performed, main control valve (2) directs pump oil to the following respective cylinders: boom, heel or tilt, grapple and stick. The pump oil is also directed to the following motors: swing and travel. Main control valve (2) contains numerous valve stems, passages, check valves, and orifices in order to carry out a single operation or a combined operation. The working pressure of the main hydraulic system is regulated by main relief valve (9).
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Cab (55) Monitor panel (55) Joystick (stick and swing) (56) Joystick (boom and heel) (57) Left travel lever/pedal (58) Right travel lever/pedal (59) Engine speed dialThe pilot hydraulic system receives oil flow from pilot pump (25). The pilot hydraulic system controls the following functions.
The pilot hydraulic system controls the operation