385B Excavator Hydraulic System Caterpillar

The specifications for the pressure, the flow rate, and the engine rpm may vary with different work tools and/or suppliers. It is very important to follow the specifications of the supplier. Failure to follow the specifications of the supplier could result in poor performance of the work tool.

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Illustration 1	g01278798

1. Use a 7X-1701 Communication Adapter or a 171-4401 Communication Adapter II in order to connect a laptop computer to the diagnostic port of the machine.

2. Place the engine start switch in the ON position. Do not start the engine.

3. Start the Electronic Technician (ET).

4. Select the "Machine Control 385B" ECM.

5. Select "Service" and then select "Tool Configuration" from the pull-down menus that are on top of the screen.

6. Select "Shear 1" from the list of tools that are available.

7. Change the value of the parameters that are shown in Table 2 through Table 3 in order to meet the specifications of your work tool.
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   Table 2

   Calibrations for Medium Pressure Circuit
   Parameter ("Description")	Value
   "Tool Program Name"
   "Maximum Throttle Dial"	"10"

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   Table 3

   "Joystick Switch Control"
   Parameter ("Description")	Value
   "Joystick #1 Switch Valve Mode"	"Med Press Ckt #1-A - ON/OFF"
   "Joystick #2 Switch Valve Mode"	"Med Press Ckt #1-B - ON/OFF"
   "Joystick #3 Switch Valve Mode"	"Aux Valve Extend - ON/OFF"
   "Joystick #4 Switch Valve Mode"	"Aux Valve Retract - ON/OFF"
   "Rocker Switch Valve Mode"	"No valve controlled"

8. Click on "Activate" in order to activate "Shear 1".
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   Table 4

   "Medium Pressure Circuit"
   Parameter ("Description")	Value
   "Med Press Ckt #1-A Max Sol Current"	Adjust current until the pressure gauge reads 1600 kPa (232.1 psi).
   "Med Press Ckt #1-A Min Sol Current"	Adjust current until the pressure gauge reads 500 kPa (72.5 psi).
   "Med Press Ckt #1-A Open Rate"	"255" (maximum speed)
   "Med Press Ckt #1-A Close Rate"	"255" (maximum speed)
   "Med Press Ckt #1-B Max Sol Current"	Adjust current until the pressure gauge reads 1600 kPa (232.1 psi).
   "Med Press Ckt #1-B Min Sol Current"	Adjust current until the pressure gauge reads 500 kPa (72.5 psi).
   "Med Press Ckt #1-B Open Rate"	"255" (maximum speed)
   "Med Press Ckt #1-B Close Rate"	"255" (maximum speed)
   "Initial Med Pres Circuit Main Pump Power Reduction"	"3.5%"
   "Total Med Pres Circuit Main Pump Power Reduction"	"7%"

9. Set the open rates and the close rates for the tool. Refer to Table 4 for the proper settings.

10. Calibrate the power reduction for the main pump. Refer to Table 4 for the proper settings.

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Illustration 2	g00727832
(1) Pressure tap ("Med Pres Ckt#1-B Solenoid") (2) Pressure tap ("Med Pres Ckt #1-A Solenoid")

11. Connect a pressure gauge to the "Med Pres Ckt #1-A Solenoid" pressure tap (2) .

    Note: The pressure range for this valve is 500 to 1600 kPa (72.5 to 232.1 psi).

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Illustration 3	g00727891
Left joystick (3) Switch (rotate counterclockwise) (4) Switch (rotate clockwise)

12. While you press switch (3), set the current value for the "Med Press Ckt #1-A Min Sol Current" to 500 kPa (72.5 psi).

13. While you press switch (3), set the current value for the "Med Press Ckt #1-A Max Sol Current" to 1600 kPa (232.1 psi).

14. Connect a pressure gauge to the "Med Pres Ckt#1-B Solenoid" pressure tap (1) .

    Note: The pressure range for this valve is 500 to 1600 kPa (72.5 to 232.1 psi).

15. While you press switch (4), set the current value for the "Med Press Ckt #1-B Min Sol Current" to 500 kPa (72.5 psi).

16. While you press switch (4), set the current value for the "Med Press Ckt #1-B Max Sol Current" to 1600 kPa (232.1 psi).

17. Exit the Electronic Technician (ET).

18. Disconnect the laptop computer from the machine.