VENT AS-FUEL TANK 4203897 - Caterpillar

Main Hydraulic Schematic
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(1) Right travel motor (2) Left travel motor (3) Swing motor (4) Main control valve (5) Boom cylinder (6) Tilt cylinder (feller buncher head) (7) Stick cylinder (8) Saw Pump (9) Implement pump (10) Pilot pump (11) Implement pump (lower) (12) Implement pump (upper) (13) Hydraulic oil tank (HH) Pressure tap (boom DOWN) (JJ) Pressure tap (boom UP) (KK) Pressure tap (tilt UP) (LL) Pressure tap (tilt DOWN) (MM) Pressure tap (stick OUT) (NN) Pressure tap (stick IN) (RR) Pressure tap (lower pump) (SS) Pressure tap (upper pump) (TT) Pressure tap (power shift)Main Hydraulic System
The main hydraulic system consists of the following components: main control valve (4), boom cylinder (5), tilt cylinder (6), stick cylinder (7), implement pump (9) and hydraulic oil tank (13).
Illustration 2 g00787002
Pump compartment (8) Saw pump. (9) Implement pump. (RR) Pressure tap (lower pump). (SS) Pressure tap (upper pump). (TT) Pressure tap (power shift).
Illustration 3 g00787013
(4) Main control valve.The main hydraulic system delivers oil flow from implement pump (9) in order to control the following components: boom cylinder (5), tilt cylinder (6), stick cylinder (7), right travel motor (1), left travel motor (2) and swing motor (3) .Implement pump (9) is made up of two variable displacement piston pumps and one gear pump. The performance of both the variable displacement piston pumps are equal. Both pumps are arranged in series. The gear pump functions as the pilot pump.The upper pump is directly connected to the engine by a coupling. The lower pump is connected to the upper pump. The upper pump and the lower pump deliver oil to the main control valve (4) .When a spool of the main control valve or the control valve (feller buncher head) is moved, a load signal is generated. The load signals control the output flow of the upper pump and the lower pump. The oil delivery from both pumps is combined at main control valve (4). The oil delivery is supplied to the cylinders (machine), the cylinders (feller buncher head), the swing motor, and the travel motors.