966F Wheel Loader and 966F Series II Wheel Loader Hydraulic System Caterpillar

2. Allow only one operator on the machine. Keep all personnel away from the machine or in the view of the operator.

3. Engage the parking brake.

4. Warm the hydraulic oil to normal operating temperature of approximately 65° ± 3°C (150° ± 5°F).

5. Begin the test for the lift cycle time with the bucket flat on the ground.

6. Increase the engine speed to high idle.

7. Pull the lift control lever back to the full RAISE position. Measure the lift cycle time. Record the lift cycle time.

8. Raise the boom to the full raised position.

9. Tilt the bucket to the full TILT BACK position.

10. Move the control lever to the full DUMP position. Measure the tilt cycle time. Record the tilt cycle time.

11. Lower the boom and place the bucket flat on the ground.

12. Reduce engine speed to low idle.

13. Stop the engine.

Note: When you perform the cycle time tests for the tilt circuit, the lift arms must be raised to the maximum height.

If the cycle times are not correct, check the following conditions:

• Check the pump flow. For additional information about implement pump flow, refer to the Service Manual module Testing and Adjusting, "Pump Performance (Implement) - Test" for the machine that is being serviced.

• Check the settings of the relief valves.

• Check the makeup valves in the main control valve.

• Check the valve spools in the main control valve.

• Check the piston seals in the cylinders.