SHAFT AS 2639219 - Caterpillar

Illustration 1 g02424196
(1) Grapple cylinders
(2) Tilt cylinder
(3) Main control valve
(4) Float solenoid valve
(5) Control valve (grapple rotate)
(6) Dump valve
(7) Oil cooler
(8) Return check valve
(9) Return line
(10) Supply line
(11) Work tool
(12) Return line
(13) Case drain return line
(14) Pressure switch
(15) Auxiliary pump for medium pressure
(16) Drain filter
(17) Return filter
(18) Hydraulic tank A medium pressure circuit is available for machines that are equipped with a butt-n-top attachment. Auxiliary pump (15) is connected to the drive pump and delivers oil flow to the medium pressure circuit.Oil flows from the auxiliary pump (15) through supply line (10) to the work tool. Oil from the auxiliary pump also flows to the control valve for grapple rotate (5). When the work tool is operated and the pressure exceeds 8270 kPa (1200 psi), pressure switch (14) is activated. The machine ECM recognizes the ON position of the pressure switch. The machine ECM then keeps the Automatic Engine Control (AEC) from reducing the engine speed while the work tool is being operated.When the work tool is not being operated, oil from the auxiliary pump flows to control valve (5) and flows across dump valve (6). From dump valve (6) the hydraulic oil returns through line (9), oil cooler (7), and to hydraulic tank (18).Tilt cylinder (2) is equipped with float solenoid valve (4). When float solenoid valve (4) is energized, the rod end and head end of the tilt cylinder are open to hydraulic tank (18). Energizing float solenoid (4) allows tilt cylinder (2) to float.Reference: For more information concerning the operation of the grapple cylinders or grapple rotate, refer to Systems Operation, "Grapple Hydraulic System".