SEAL KIT 1033639 - Caterpillar

Swing Operation
Right Swing
Illustration 3 g03393704
Hydraulic schematic for the swing system RIGHT SWING "clockwise" operation shown (1) Solenoid for clockwise swing (2) Solenoid for counter-clockwise swing (3) Pilot oil supply port "PS" (4) Pilot pressure sensor (5) Pressure reducing valve (6) Swing brake solenoid valve (7) Control manifold and solenoid for swing (8) Swing pump (9) Throttle piston (10) Charge filter for swing pump (11) Diagnostic port for swing circuit "S2"(Port B) (12) Charge pump (13) Hydraulic oil tank (14) Case drain filter for swing (15) Swing brake (16) Swing motor (17) Case drain filter line for swing (18) Manifold and valve for swing cooling (19) Diagnostic port for swing circuit "S1"(Port A) (20) Supply line from tank (21) Swing pump pressure sensor (22) Pressure cutoff valve (23) Charge relief valve (24) Crossover relief valve (25) Actuator pistonWhen the hydraulic lockout control lever is in the UNLOCKED position, the pilot oil delivery from the main control valve flows to control manifold and solenoid (7) through port (3) .Charge pump (12) is used to keep the closed loop swing system charged with oil and charge pump (12) provides cooling and lubrication.During the swing operation, swing pump (8) is upstroked to direct flow to the swing motor.During a swing to the right, the swing joystick is moved to the SWING RIGHT position. The upper controller energizes swing brake solenoid valve (6) and swing solenoid valve (1). The spool of swing brake solenoid valve (6) shifts right. Pilot oil flows through port "S1" to swing brake (15). The swing brake releases in order to enable a swing operation.The spool for clockwise swing solenoid (1) in control manifold and solenoid (7) shifts right. This action sends pilot oil to port "Y1" in throttle piston (9). Pilot oil flows through throttle piston (9) to left side of actuator piston (25). Oil on the back side of swash plate (25) is relieved to tank (13) through throttle valve (9) and control manifold and solenoid (7). With actuator piston (25) moved from center, oil within swing pump (8) will pressurize and flow to the following components: crossover relief valve (24), pressure cutoff valve (22), valve and manifold (18), diagnostic port (19), port "A" and swing motor (16). The oil enters swing motor (16) and the motor rotary group rotates. The upper structure swings to the right (clockwise direction).The oil delivery for the swing hydraulic circuit is supplied by charge pump (12) only. Charge pump (12) provides a constant supply of charge oil for swing pump (8). Swing pump (8) is supplied from the return oil of swing motor (16) and from charge pump (12) through charge pump filter (10) and crossover relief valve (24). When oil is not needed by swing pump (8) through crossover relief valve (24), oil will drain to hydraulic oil tank (13) through charge relief valve (23) .Return oil from motor rotary group (16) flows through line (17) to case drain filter (14) to hydraulic oil tank (13). The return oil also flows