The procedure will check the pressure at the relief valve for proper operation and correct pressure of the system.
| Required Tool | ||
| Part Number | Description | Quantity |
| 6V-4161 | Hydraulic Test Group | 1 |
 |
Personal injury or death can result from sudden machine movement. Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To help prevent possible injury before testing and adjusting any hydraulic system, perform the procedure that follows: |
 |
Before you start the test procedure, complete the following procedure:
- Machine Preparation for Troubleshooting
Reference: For more information on preparing the machine for troubleshooting, refer to the Service Manual module Systems Operation/Testing and Adjusting, "Machine Preparation for Troubleshooting" for the machine that is being serviced.
Relief Valve Pressure Check
 | |
| Illustration 1 | g00590005 |
Front Axle (1) Pressure tap. (2) Relief valve. (3) Locknut. (4) Adjusting screw. | |
The following procedure will check the pressure for both differential locks.
- Engage the parking brake. Remove the plate on the front axle guard.
- Connect a 4135 kPa (600 psi) gauge to pressure tap (1) .
- Start the engine. Run the engine at high idle.
- Move the differential lock switch to the ON position. The pressure reading should be 2580 ± 100 kPa (375 ± 15 psi).
- If the differential lock pressure is not within specifications, adjustment is necessary.
- Stop the engine.
- Loosen locknut (3). Turning adjustment screw (4) clockwise will increase the system pressure. Turning adjustment screw (4) counterclockwise will decrease the system pressure.
- Check the new setting of relief valve (2). Repeat Steps 3 through 6. If the pressure setting is correct, tighten locknut (3) and disconnect the gauge from pressure tap (1) .
- Install the plate on the front axle guard.
Note: Use this same procedure with machines that are equipped with a winch.