M314F and M316F Wheeled Excavators Hydraulic System Travel Motor (Destroke Point) - Test and Adjust Caterpillar

Specification

Introduction

This procedure is only performed if the travel motor calibration fails.

Note: Prior to performing this test, the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust" and Testing and Adjusting, "Travel Motor (Upstroke Point) - Test and Adjust" must be performed.

Required Tools

Illustration 1	g01623868
Tooling (B) 198-4240 Digital Pressure Indicator Gp

Machine Preparation

1. Clear all personnel from the machine and from the area around the machine.

2. Start the engine.
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   Illustration 2	g02449876
   Engine speed dial

3. Set the engine speed dial at "10".

4. Lower the left console.

5. Position the machine on level ground. Check the visibility and adjust the mirrors for the best vision close to the machine.

6. Fully depress the service brake pedal until the service brake pedal locks mechanically.

7. Increase the hydraulic oil temperature to 46° to 60° C (115° to 140° F).

8. Stop the engine.

9. Release the pressure in the hydraulic system.

   Note: Refer to Testing and Adjusting, "System Pressure - Release".

10. Raise the left console.
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    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 attachments have been lowered, 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.

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    NOTICE
    Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products. Dispose of all fluids according to local regulations and mandates.

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    Illustration 3	g03736528
    Pilot manifold (1) Port plug ( port "M8")

11. Remove the fitting at "M8" (1) and install tooling (F).

12. Attach Tooling (B2) 3,445 kPa (500 psi) pressure sensor to port "M8" (1).
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    Illustration 4	g03722485
    Service connector on the right side of cab behind the seat

13. Connect tooling (E) to the service connector.

14. Clear all personnel from the machine and from the area around the machine.

15. Start the engine.
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    Illustration 5	g02452604
    Engine speed dial

16. Set the engine speed dial at "1".

    Note: Do not activate any implements.

17. Lower the left console.

18. Lower the stabilizers, the blade tip, and/or the implement to raise the front axle and the rear axle. This step will allow the wheels to turn freely.

    Note: All tires must be fully off the ground.

19. Fully extend the bucket cylinder and place the bucket on the ground.
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    Illustration 6	g02446738
    Power mode control button on the soft panel switch

20. Push down on the power mode control button to activate power mode.

    Note: The indicator light will be illuminated when power mode is activated.

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    Illustration 7	g02453444
    Transmission control button on the soft panel switch

21. Push down on transmission control button to select FIRST GEAR.

    Note: The first indicator light will illuminate when the transmission is in FIRST GEAR.

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    Illustration 8	g02447036
    Automatic Engine Speed Control (AESC) as displayed on the programmable function key in the monitor.

22. Disable the automatic engine speed control through the monitor by pressing the programmable button.
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    Illustration 9	g03722432
    Hydraulic modulation switch on left joystick

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    Illustration 10	g06186138
    Hydraulic modulation aggressive mode (monitor display)

23. Select the hydraulic modulation mode as aggressive. Press the lower front switch on the left joystick to select the hydraulic modulation mode.

24. The air conditioning should be turned off for the following test.

25. Override the "Travel Motor Swashplate Angle Limit Solenoid Current Override" in the step sequence below to perform the check procedure and/or test procedure.

    1. Start Electronic Technician.

    2. Select the "Machine ECM" from the list of available controls.

    3. From the top menu, select "Diagnostics".

    4. From the pull-down menu, select "Diagnostic Tests".

    5. Then select "Override Parameters".

    6. Select "Travel Motor Swashplate Angle Limit Solenoid Current Override" and adjust the current to 0.0 amp.

    7. Select "Travel Forward Select Solenoid Override" and turn the solenoid to ON.

    8. Select "Travel Pilot Solenoid Current Override" and adjust the current to 0.9 amp.

26. If the cause of the failure is not known, proceed to the"Check Procedure"to verify the complete curve for the destroke points. If the cause of the failure is known, proceed to the"Test Procedure"to verify that the destroke pressure is within specifications.

Check Procedure

Note: The travel motor and transmission can be damaged if the speed of the transmission exceeds 1000 rpm while in first gear.

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To prevent injury or death, never work under a machine while a test is being performed.

1. Release the service brake pedal.

2. Depress the travel speed pedal fully in the FORWARD position.

3. Monitor the "Transmission Output Speed", and slowly increase the current value to the "Travel Motor Swash Plate Angle Limit Solenoid Current Override" by increments of 0.02 amp until the pressure at port "M8" (1) has reached the desired destroke pressure in Table 3.

4. Compare the transmission output speed and travel motor swashplate angle limit solenoid current with the pressure at port "M8" (1).

5. Repeat the"Check Procedure"for more destroke points that are listed in Table 3.

6. Release the travel pedal.

7. Fully depress the service brake pedal until the service brake pedal locks mechanically.

8. Stop the engine.

9. Release the pressure in the hydraulic system.

   Note: Refer to Testing and Adjusting, "System Pressure - Release".

10. Raise the left console.

Test Procedure

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To prevent injury or death, never work under a machine while a test is being performed.

1. Release the service brake pedal.

2. Depress the travel speed pedal fully in the FORWARD position.

3. Monitor the "Transmission Output Speed", and slowly increase the current value to the "Travel Motor Swash Plate Angle Limit Solenoid Current Override" by increments of 0.02 amp until the transmission output speed increases.

4. Check the pressure gauge at port "M8" (1) to verify that the pressure has increased to the proper specification when the transmission speed increases. Refer to Table 1 for the correct pressure.

5. Release the travel pedal.

6. Fully depress the service brake pedal until the service brake pedal locks mechanically.

7. If the destroke pressure is not set to the proper specification, proceed to the"Adjustment Procedure"to adjust the destroke pressure.

Adjustment Procedure

Note: If the original cap is on the destroke pressure adjustment screw, do not make adjustments until the root cause of failure has been verified.

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

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Illustration 11	g06072889
Travel motor M314F (2) Destroke adjustment screw

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Illustration 12	g03736531
Travel motor M316F (2) Destroke adjustment screw

1. Stop the engine.

2. Raise the left console.

3. Loosen the locknut on destroke adjustment screw (2).

4. Turn destroke adjustment screw (2) clockwise to decrease pressure. Turn destroke adjustment screw (2) counterclockwise to increase the pressure.

   Note: A quarter turn of destroke adjustment screw (2) will equal approximately 200 kPa (29 psi).

   Note: Always make the final pressure adjustments on the pressure rise.

5. While destroke adjustment screw (2) is being held, tighten locknut to the specified torque.

6. Repeat Step 14 through Step 26 of the"Machine Preparation"and complete the "Test Procedure", until the destroke pressure is within specifications.

7. Once the destroke pressure has been met, disable all overrides in Cat (ET).