LINES GP-TURBOCHARGER AIR 1566233 - Caterpillar

Lift Control Valve (FLOAT Position)
When the lift pilot valve is in the FLOAT position, pilot oil pressure at port (G) overcomes the force of spring (21) and spool (18) will shift. The detent in the lift pilot valve allows pilot oil to continue to flow to port (G). The lift control valve (3) is in the FLOAT position. For more information on the operation of the lift pilot valve, refer to Systems Operation, "Pilot Hydraulic System".When the lift control valve (3) is in the FLOAT position, implement supply oil flows to the lift control valve through passage (16). The supply oil flows around spool (18) and into passage (20). Passage (20) is the open center passage that leads to the outlet. Implement supply oil also flows to the lift control valve through passage (17). Check valve (15) allows the supply oil in passage (17) to pressurize passage (23). Spool (18) opens the head end of the lift cylinder through port (K) and the rod end of the lift cylinder through port (J) to tank through return passage (10). The lift cylinder moves the work tool to the FLOAT position.Lift Control Valve (Dead Engine Lower)
If the engine is dead, manual valve (26) can be used to lower the implement. The manual valve is located on the bottom of the right-hand side of the machine Just in front of the right wheel The manual valve (26) is connected into tees in both lines (D) and (C) When valve (26) is turned spool (18) will shift. The head end of the lift cylinder through port (C) will be open to the tank through return passage (10). The weight of the work tool will create a decrease in pressure in the rod end of the lift cylinder and port (C). Makeup valve (24) will open, and port (C) will be connected to the tank through return passage (10) .Tilt Control Valve
Illustration 5 g03797742
(10) Return passage (14) Pilot passage (15) Check valve (16) Open center passage from inlet to tilt control valve control (17) Parallel oil passage (18) Spool (19) Spring (20) Open center passage from tilt control valve to lift control valve (21) Spring (22) Pilot passage (23) Internal passage (24) Makeup valve (25) Line relief valve (Dump) (26) Manual valve (27) Line Relief valve (Tilt Back) (L) Port for the pilot line for LOWER (A) Port for the head end of the lift cylinder (B) Port for the rod end of the lift cylinder (M) Port for the pilot line for RAISEThe tilt control valve (2) controls the tilt cylinder. The tilt control valve has the following three positions: HOLD, DUMP and TILT BACK. The pressure of the line relief valves (25) and (27) are set above the main relief valve pressure setting.Tilt Control Valve (HOLD Position)
When the tilt pilot valve is in the HOLD position, ports (L) and (M) are open to the tank. Springs (19) and (21) hold spool (18) centered. The tilt control valve (2) is in the HOLD