BLOCK 2019378 - Caterpillar

Illustration 1 g03381467
(1) Stick cylinder
(2) Stick lowering control valve
(5) Manual stick lower
Illustration 2 g03527936
Partial schematic
(1) Stick cylinder
(2) Stick lowering control valve
(3) Main control valve
(4) Pilot control valve (stick and swing)
(5) Manual stick lower STICK OUT Operation
Illustration 3 g03539296
(6) Port
(7) Passage
(8) Check valve
(9) Spring
(10) Passage
(11) Passage
(12) Port (cylinder)
(13) Port (pilot)
(14) Spool
(15) Spring
(16) Valve
(17) Spool
(18) Seat
(19) Orifice
(20) Passage
(21) Line relief valve
(22) Tank port
(23) Manual stick lower
(24) Passage
(25) Drain port When the operator moves the joystick to the STICK OUT position, the pump oil flows from the main control valve through a line to port (6) of the stick lowering control valve. The pump oil flows into passage (7) and the pressure of the pump oil causes check valve (8) to shift downward against spring (9). The pump oil flows through passage (10) to passage (11). Then, the pump oil flows from passage (11) to port (12) at the rod end of the stick cylinder. The rod of the stick cylinder will retract in order to move out the stick.When the joystick is returned to the NEUTRAL position, the stick cylinder remains with out position. Check valve (8) and valve (16) prevent the oil in the rod end of the stick cylinder from flowing out of the stick cylinder.STICK IN Operation
Illustration 4 g03539298
(6) Port
(7) Passage
(8) Check valve
(9) Spring
(10) Passage
(11) Passage
(12) Port (cylinder)
(13) Port (pilot)
(14) Spool
(15) Spring
(16) Valve
(17) Spool
(18) Seat
(19) Orifice
(20) Passage
(21) Line relief valve
(22) Tank port
(23) Manual stick lower
(24) Passage
(25) Drain port When the operator moves the joystick to the STICK IN position, pump oil flows from the main control valve through a line that is ported to the head end of the stick cylinder.Simultaneously, pilot oil flow is provided to port (13) of the stick lowering control valve. The pilot oil at port (13) will cause spool (14) to shift to the left. Spool (14) will force spool (17) to move to the left against spring (15).The oil in the rod end of the stick cylinder begins to flow to port (12) of the stick lowering control valve. As oil flows into passage (11), check valve (8) will remain closed. As pressure begins to rise in passage (11), spool (17) will begin to move to the left and oil will flow to passage (20). The oil then flows from passage (20) to port (6). From port (6), the oil will flow through a line to the main control valve and back to the hydraulic tank.When the joystick is returned to the NEUTRAL position, the loss of pilot oil pressure will allow spring (15) to force spool (17) and valve (16) to close. Oil in the rod end of the stick cylinder is trapped and the stick cylinder is held in position.Manual Stick Lowering
Illustration 5 g03385767
(26) Port
(27) Seat
(28) Locknut
(29) Valve
(30) Ball
(31) Port As seat (27) is turned counterclockwise, ball (30) will shift. As ball (30) is shifted, oil is allowed to flow through port (31) and valve (29) to port (26). Oil from the rod end of the stick cylinder flows through port (26) to the