312C and 315C Excavators Tool Control System Caterpillar

Note: Adjustment procedures must be performed before a test and adjustment of any line relief valve pressure setting is attempted. A temporary setting of the main relief valve pressure is required before any line relief valve pressure setting is adjusted. Refer to the adjustment procedures in Testing And Adjusting, "Relief Valve (Main) - Test and Adjust".

Since the pressure specifications, the flow rate, and engine rpm may vary with types and/or suppliers of a work tool, 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.

1. Position the machine on level ground.

2. Ensure that the procedures for setting up the work tool have been performed. See Testing and Adjusting, "Process for Setting Up the Work Tool" for the steps that are required to set up a work tool. This procedure for setting the relief valve is the last step in the process.

3. Stop the engine.

4. Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release".

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Illustration 1	g00983925
Pump compartment (1) Pressure tap (Drive pump ) (2) Pressure tap (Idler pump) (3) Pressure tap (power shift pressure)

5. Connect a 60000 kPa (8700 psi) pressure gauge to pressure tap (1) .

6. Connect a 60000 kPa (8700 psi) pressure gauge to pressure tap (2) .

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Illustration 2	g00771352
(4) Boom (5) Stick (6) Ball valve for work tool

7. Close the ball valve for the work tool at the end of the stick.

8. Turn the disconnect switch to the ON position.

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Illustration 3	g00685772
(7) Up key (8) Left key (9) Right key (10) Down key (11) Cancel key (12) Set key (14) OK key (13) Menu key

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Illustration 4	g00783871
Default display screen

9. Turn the key switch to the ON position. The default display screen will show on the display area.

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Illustration 5	g00786650
Main menu display

10. Press Menu key (13) in order to change from the default screen to the main menu display.

11. Press Down key (10) in order to highlight the " Select Tool" option. When the "Select Tool" option is highlighted, press the OK key (14) .

12. The current tool is shown. After a few seconds, you will be prompted to enter a password.

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Illustration 6	g00786656

13. Press Left key (8) or Right key (9) in order to select the desired position. Press Up key (7) or Down key (10) in order to input the password.

    Note: The password is alphanumeric. You may choose from "0" to "9". You may choose from "A" to "F". The initial password is "0001".

14. Press OK key (14) after you enter the password.

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Illustration 7	g00786666

15. The tool that is selected is shown after you enter the "Select Tool" menu.

16. Press Right key (9) or Left key (8) in order to scroll through the different tools. Highlight the correct auxiliary tool and press Set key (12) .

17. Start the engine.

18. Place the machine controls at the following settings: the engine speed dial at 10 and the AEC switch OFF. Refer to Testing and Adjusting, "Engine Performance Test" for engine rpm settings.

19. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F).

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Illustration 8	g00772513
(14) Line relief valve

Note: The pressure setting from the factory for the line relief valves in the hydraulic circuit for one-way flow is 36800 ± 1470 kPa (5350 ± 215 psi).

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Illustration 9	g00885044
(14) Locknut (15) Adjustment screw

20. Activate the hydraulic circuit for one-way flow and read the gauge. The pressure must be set to the pressure that is recommended by the manufacturer of the tool plus 3447 kPa (500 psi).

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Illustration 10	g00343372
Line relief valve (typical example) (14) Locknut (15) Adjustment screw

21. If the pressure gauge reading on pressure tap (2) is too high, go to step 22. If the pressure gauge reading on pressure tap (2) is too low, perform the following steps:

    1. Deactivate the hydraulic circuit for one-way flow.

    2. Loosen locknut (14). Turn adjustment screw (15) clockwise.

    3. Tighten locknut (14) .

       Torque for locknut (15) ... 50 ± 10 N·m (37 ± 7 lb ft)

    4. Activate the hydraulic circuit for one-way flow.

    5. Repeat steps 21.a through 21.d in order to set the specified pressure.

22. If the pressure gauge reading on pressure tap (2) is above the specification perform the following steps:

    1. Deactivate the hydraulic circuit for one-way flow.

    2. Loosen locknut (14). Turn adjustment screw (15) counterclockwise.

    3. Tighten locknut (14) .

       Torque for locknut (15) ... 50 ± 10 N·m (37 ± 7 lb ft)

    4. Activate the hydraulic circuit for one-way flow.

    5. Repeat steps 22.a through 22.d in order to set the specified pressure.