STICK BOOM S 0788333 - Caterpillar

HOLD Position
Illustration 1 g03167276
(1) Spool (2) Passage (3) SpringIn the HOLD position, the spring (3) holds spool (1) in the centered position. The spool (1) blocks the flow of pump supply oil in passage (2) .Passage (2) is common to all control valves in the bank valve. The passage has no outlet. The spool blocks the flow of pump supply oil until the operator moves the mechanical Backhoe controls.UP Position
Illustration 2 g03167278
(1) Spool (2) Port for head end (3) Port for rod end (4) Spring (5) Passage (6) Passage (7) Passage (8) Passage (9) Passage (10) Passage (11) PassageWhen the stab up circuit is the only hydraulic circuit in operation, the stabilizer circuit will have the highest signal oil pressure in the hydraulic system. When the stabilizer control lever is moved to the stabilizer UP position, spool (1) moves up spring (4) compressed.When the spool moves up, pump supply oil flows from passage (8) around the spool and into passage (9) .The signal oil in the internal passage flows to the pressure compensator valve in each control valve. The signal oil also flows to the pressure and flow compensator valve on the hydraulic pump. The signal oil helps to control the output of the hydraulic pump. The hydraulic pump upstrokes and the hydraulic oil pressure in passage (8) and passage (9) increases. The hydraulic oil flows to passage (7) and passage (10).