FLUID-UREA 3508733 - Caterpillar

Swing Motor with Fine Swing (If Equipped)
Illustration 2 g03376743
Partial schematic
(7) Swing motor
(14) Main control valve
(21) Drive pump
(23) Idler pump
(24) Pilot pump
(40) Hydraulic tank
(41) Fine swing solenoid Hydraulic Schematic with Heavy Lift
Illustration 3 g03376745
Partial schematic
(14) Main control valve
(24) Pilot pump
(34) Pilot oil manifold
(40) Hydraulic tank
(42) Main relief valve
(43) Heavy lift solenoid Hydraulic Pump Flow and Pressure Control System
Illustration 4 g02178529
Pump compartment
(21) Drive pump
(22) Proportional reducing valve (power shift pressure)
(23) Idler pump
(24) Pilot pump
(44) Delivery line (drive pump)
(45) 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, and the travel motors.
The electronic control system controls the outputs of the engine and pumps.The main hydraulic system delivers oil flow from idler pump (23) and drive pump (21) in order to control the following components: bucket cylinder (4), stick cylinder (3), boom cylinders (5), right travel motor (9), left travel motor (8) and swing motor (7).
Illustration 5 g02186553
Main control valve
(14) Main control valve body
(30) Main relief valve Drive pump (21) and idler pump (23) are variable displacement piston pumps. The performance of both pumps is equal.Drive pump (21) is directly connected to the engine by a flexible coupling. Idler pump (23) is mechanically connected to the drive pump through gears. The drive pump and the idler pump deliver oil to main control valve body (14). The drive pump delivers oil to the left travel control valve, the boom I control valve, the bucket control valve, and the stick II control valve. The idler pump delivers oil to the right travel control valve, the boom II control valve, the swing control valve, and the stick I control valve. Pilot pump (24) is a gear pump that supplies oil to the pilot hydraulic system. Pilot pump (24) is mechanically connected to idler pump (23) through gears. 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 identical to the engine horsepower.When no work is being performed, pump oil flows through main control valve (14) and into hydraulic tank (40). 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 (14) directs pump oil to the respective cylinders (boom, bucket, and stick) and/or motors (swing and travel). Main control valve (14) contains numerous valve stems, passages, check valves, orifices, and electronic solenoids 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 (30).
Illustration 6 g02186593
Cab
(46) Monitor panel
(47) Joystick (stick and swing)
(48) Joystick (bucket and boom)
(49) Left