D6K2 and D6K Track-Type Tractor Systems Caterpillar

Show/hide table

Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury or death to persons on or near the machine. To prevent injury or death, make sure that the area around the machine is clear of all personnel and obstructions before you test the machine.

Show/hide table

Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the work tools have been lowered to the ground, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

Specifications

Introduction

The crossover relief valves are tested with Caterpillar Electronic Technician (ET). The technician follows the instructions on the ET calibration screen. The test will make sure that the winch pump is providing the correct pressure to each loop of the winch motor.

Required Tools

Illustration 1	g03823692
Tooling (B) 466-6259 Communication Adapter Gp

Test Preparation - Crossover Relief Valve

1. Move the machine to a smooth, horizontal location that is away from operating machines and away from personnel.

2. Permit only one operator on the machine. Keep all other personnel away from the machine or in the operator sight.

3. Place the steering control lever in the NEUTRAL position.

4. Engage the parking brake.

5. Lower the attachments to the ground.

6. Stop the engine.

   Note: The monitoring system (if equipped) for your machine accesses many values that are useful in troubleshooting the hydraulic system. When the situation is appropriate, use the monitoring system to find a pressure or determine a system problem.

   Show/hide table

   Illustration 2	g06023148

7. Remove cover (2).

8. Connect Tooling (B) to service tool connector (E1).

9. Remove the rear bottom guard.

   Note: The pressure override valve can also be reached from the top by removing the floorplate from the cab.

   Show/hide table

   Illustration 3	g03736171

10. Locate winch pump (3). The winch pump is the second pump in the series.

11. Locate pressure override valve (4) on the winch pump.
    Show/hide table

    Illustration 4	g03737479

12. Remove cap (5) from pressure override valve (4).
    Show/hide table

    Illustration 5	g01337977

13. Mark the position of adjustment screw (6).

14. Loosen locknut (7). Maintain the position of adjustment screw (6).

15. Turn adjustment screw (6) clockwise for one full turn to increase the pressure.

16. Tighten locknut (7). Maintain the position of adjustment screw (6).

17. Connect the computer and the communication adapter group to the communication port on the tractor.

18. Open Caterpillar Electronic Technician (ET).

19. Select the machine ECM.
    Show/hide table

    Illustration 6	g01337741

20. Select the "Diagnostics" drop-down menu.

    From the drop-down menu, select the "Diagnostic Tests". From the "Diagnostic Tests" menu, select the "Winch Stall Test".

Testing Procedure - Crossover Relief Valve

Note: Ensure that the charge oil pressure is set correctly before you perform the stall test. Refer to Testing and Adjusting, "Charge Relief Valve (Winch) - Test and Adjust". Failure to check the charge oil pressure could result in problems when you perform the stall test for the winch.

1. Warm the hydraulic oil to 55° ± 10°C (131° ± 18°F) or warm the hydraulic oil to the range specified by (ET).

2. Turn the engine throttle knob clockwise to the HIGHEST position.

3. Record the engine RPM.
   Show/hide table

   Illustration 7	g01337863

4. Follow the instructions on Caterpillar Electronic Technician (ET).

5. Move the winch control to the full REEL IN position. No drum motion is allowed.

   Note: Do not stall the system at high pressure for more than 15 seconds.

6. Record the "Winch Motor Pressure" while the winch is stalled.

   Note: The "Winch Motor Pressure" is displayed on the ET screen.

   1. The "Winch Motor Pressure" should be 44000 ± 1000 kPa (6380 ± 145 psi).

7. Move the winch control to the full REEL OUT position. No drum motion is allowed.

   Note: Do not stall the system at high pressure for more than 15 seconds.

8. Record the "Winch Motor Pressure" while the winch is stalled.

   Note: The "Winch Motor Pressure" is displayed on the ET screen.

   1. The "Winch Motor Pressure" should be 44000 ± 1000 kPa (6380 ± 145 psi).

9. Return the winch control to the HOLD position.

10. Turn the engine throttle knob counterclockwise to the LOWEST position.

11. Determine if the "Winch Motor Pressure" is not correct in either direction.

12. If the pressure is not within the specification in both directions, adjust the pressure override valve. Refer to Testing and Adjusting, "Pressure Override Valve (Winch) - Test and Adjust". Then, perform the test again.

    If the pressure is not within the specification in only one direction, the crossover relief valve for that circuit may need to be adjusted. Exchange the two crossover relief valves and perform the stall test again. If the problem follows the exchanging of the crossover relief valves, adjust the crossover relief valve for that circuit. Proceed to "Adjusting Procedure - Crossover Relief Valve".

13. If the crossover relief valves are within the specified limits, return the pressure override valve to the original position.

Adjusting Procedure - Crossover Relief Valve

1. Move the machine to a smooth, horizontal location that is away from operating machines and away from personnel.

   Note: Permit only one operator on the machine. Keep all other personnel away from the machine or in the sight of the operator.

2. Place the steering and transmission control lever in the NEUTRAL position.

3. Engage the parking brake.

4. Lower the attachments to the ground.

5. Stop the engine.

6. Turn the key to the ON position, but do not start the engine.

7. Verify that the implement shutoff control is not activated.

8. Move the control levers through the full range of travel several times. This will relieve any pressure that may be present in the implement hydraulic system.

9. Remove the rear bottom guard.

   Note: The crossover relief valves can also be reached from the top by removing the floorplate from the cab.

   Show/hide table

   Illustration 8	g03736670

10. Locate winch pump (3). The winch pump is the second pump in the series.
    Show/hide table

    Illustration 9	g03736671

11. Locate crossover relief valves (8) on the winch pump.
    Show/hide table

    Illustration 10	g03737478

12. Loosen locknut (10). Maintain the position of adjustment screw (9).

13. Turn adjustment screw (9) to adjust the pressure. Turn the adjustment screw counterclockwise to decrease the pressure. Turn the adjustment screw clockwise to increase the pressure. One full turn is approximately 6400 kPa (930 psi).
    Show/hide table

    NOTICE
    If the adjustment screw bottoms out when you turn the adjustment screw clockwise, do not exceed a torque of 2 N·m (18 lb in). Damage to the valve could result if you exceed this torque.

    Note: When you adjust the crossover relief valve to decrease the pressure, turn the adjustment screw for an additional one quarter turn past the estimated adjustment setting. Then, turn the adjustment screw clockwise for one quarter turn.

14. Tighten locknut (10). Do not allow adjustment screw (9) to rotate when locknut (10) is tightened.

15. Repeat the stall test. Continue to adjust the crossover relief valves until the pressure is within the given specification.

16. Make sure that the pressure override valve has been returned to the original position by performing the Testing and Adjusting, "Pressure Override Valve - Test and Adjust".

17. When the pressure override valve is set correctly, replace the bottom guard and the floorplate.