BAR GP-EQUALIZER 1196912 - Caterpillar

Propel Lever in the REVERSE Position, Parking Brake Switch in the OFF Position, and Propel Range Switch in the HIGH SPEED Position
Illustration 4 g00940698
Hydraulic Schematic (3) Thermal bypass valve and return manifold (4) Axle motor (5) Axle propel pump (6) Drum propel pump (7) Axle interlock valve (8) Drum interlock valve (9) Directional control valve (10) Directional control valve (11) Charge filter (12) Drum motor (13) Drum brake (16) Line from steering pump (17) Shift valve (24) Line from vibratory motor (25) Line from vibratory pump (26) Servo piston (27) Flushing spool (28) Flushing relief valve (30) Shift spool (31) Servo piston (32) Reverse combination valve (33) Forward combination valve (34) Charge relief valve (35) POR valve (36) Servo piston (37) Forward combination valve (38) Reverse combination valve (39) Charge relief valve (40) POR valve (41) Servo piston (42) Shift spool (43) Flushing relief valve (44) Flushing spool (45) Reverse balance line (46) Forward balance line (AA) System pressure (AB) Charge pressure (AC) Sump (AD) Activated components (AE) First pressure reductionThe hydraulic schematic in Illustration 4 shows the propel system in the following condition:
The propel lever in the REVERSE position
The parking brake switch in the OFF position
The propel range switch in the HIGH SPEED positionCharge Pressure Oil
The charge pressure oil provides makeup oil and charge oil for the following functions:
Charge pressure oil for the propel pumps
Charge oil for the hydraulic circuit for any motor leakage
Cooling for the propel pumps and the motors
Oil pressure for moving the servo pistons for the propel pumps
Oil for releasing the parking brake
Oil for the shift valve that is used to change the displacement of the motor for high speed or low speed Charge pressure oil for the propel pumps is provided from steering pump (30) when the engine is running.Charge pressure oil flows through charge filter (11) and to the following components:
Axle interlock valve (7)
Drum interlock valve (8)
Shift valve (17)
Reverse combination valve (32) (axle propel pump)
Forward combination valve (33) (axle propel pump)
Forward combination valve (37) (drum propel pump)
Reverse combination valve (38) (drum propel pump)
Charge relief valve (34) (axle propel pump)
Charge relief valve (39) (drum propel pump)Charge pressure oil acts on charge relief valve (34) and (39). When the charge pressure oil reaches the adjusted pressure setting, the oil pressure will overcome the spring force in the relief valve. As a result, the excess oil flow will be directed through the case drain and to the thermal bypass and return manifold.Parking Brake Switch in the OFF Position
When the parking brake switch is in the OFF position, the solenoids for axle interlock valve (7) and drum interlock valve (8) will be energized. On machines that do not have axle brakes, the drum interlock valve will allow charge pressure oil to fill the brake piston cavity. As a result, the charge pressure oil will overcome the springs in drum brake (13) and the brake will be released.Propel Range Switch in HIGH SPEED Position
When the propel range switch is in the HIGH SPEED position, the solenoid for shift