CYLINDER HEAD GP 5087703 - Caterpillar

One-Way Flow from One Pump
One-way flow from one pump can be achieved by selecting a work tool that requires one-way flow from one pump. The work tool can be selected through the monitor or by the work tool select switch. A typical example is a hammer that receives oil from one pump only. This operation allows oil to flow directly to the oil cooler and through the main control valve. The return of oil directly to the cooler will allow for a higher flow of oil with the reduction of resistance by bypassing the main control valve.When one pump flow is required to the work tool, the pump supplying the oil can be programmed through the monitor.Reference: Refer to Testing and Adjusting, "Work Tool Parameter - Program" for the tool control system to change the settings for work tool operation.Reference: Refer to Testing and Adjusting, "One-Way/One Pump: Default Value of Work Tool Parameters" for the Tool Control System to reference the factory settings.
Table 1
Operation Lever List
Control Extension
Joystick Thumb wheel Push Forward
Electric Foot Pedal Push Forward
Illustration 1 g06271602
One-Way Flow from One Pump
(1) Hydraulic oil cooler
(2) Pilot pressure reducing valve
(3) Main control valve
(4) Main relief valve
(5) Proportional reducing valve (A1 extend)
(6) Line relief valve (Auxiliary 1 head end)
(7) Line relief valve (Auxiliary 1 rod end)
(8) Hydraulic lock solenoid
(9) Pump 2 output pressure sensor
(10) Pump 1 output pressure sensor
(11) Attachment control valve (pump 1)
(12) Proportional reducing valve (A1 retract)
(13) f2 stack valve
(14) Hydraulic tank
(15) Pump 1 control solenoid
(16) Pump 1
(17) Pump 2
(18) Pump 2 control solenoidWhen the device for activation listed in Table 1 is pushed forward, the machine ECM sends a modulated signal to proportional reducing valve (5). Proportional reducing valve (5) allows pilot oil to flow to the attachment control valve (11), allowing high-pressure oil from pump 1 (16) to flow to the work tool.A portion of the oil returning from the work tool flows back through attachment control valve (11) and back to the hydraulic tank. Also, oil returning from the work tool flows directly to the cooler (1) and back to the hydraulic tank (14).During the operation of the work tool, the oil flow for pump 1 (16) is controlled by the machine ECM.