Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To prevent possible injury, perform the procedure that follows before testing and adjusting the power train. |
Before you perform these procedures, refer to Testing and Adjusting, "Machine Preparation" for the correct procedure for machine preparation.
The following operational checks can be used for the following items:
- find leakage in the system.
- determine whether the joystick controls are functioning correctly.
- determine whether the pump or motors are functioning correctly.
- determine whether the whole work tool system is functioning correctly.
In order for the hydraulic system to function properly, each component in the system must be set to the correct specifications. Some components must be set prior to the testing of other components. A component that is not set properly will have an impact on other components in the system.
Note: The oil in the hydraulic system must be at an operating temperature range of 50° ± 10°C (122° ± 18°F). In order to increase the oil temperature, start the engine and operate all the cylinders for at least five cycles. Also, drive the machine forward and drive the machine rearward.
Lift Cylinder Speed Test
Note: Perform the lift cylinder speed test with an empty general purpose bucket. If a general purpose bucket is not available, then use a load weight of 200 kg (441 lb).
- Fasten the seat belt and lower the armrest.
- Start the engine.
- Disengage the parking brake.
- Run the engine at high idle with the speed and direction control in the HOLD position.
- Operate the lift cylinder through at least five lift cycles. This will ensure that there is warm oil in the lift cylinders.
- Tilt the bucket to the full TILT BACK position. Lower the bucket to the full LOWER position.
- Raise the bucket from the full LOWER position. Record the time from the full LOWER position to the full RAISE position.
- Lower the bucket from the full RAISE position. Record the time from the full RAISE position to the full LOWER position.
- Raise the bucket to the full RAISE position. Move the work tool control to the FLOAT position. Record the time from the full RAISE position to the full LOWER position.
TRAVEL TIME (SPEED) FOR THE LIFT CYLINDERS     | |
Position of the Work Tool Control     | 236/246     |
RAISE     | 2.7 ± 0.2 seconds     |
LOWER     | 2.7 ± 0.2 seconds     |
FLOAT     | 2.8 ± 0.2 seconds     |
If the speeds are not correct, refer to the Testing and Adjusting, "Hydraulic System Troubleshooting".
Tilt Cylinder Speed Test
Note: Perform the tilt cylinder speed test with an empty general purpose bucket. If a general purpose bucket is not available, then use a load weight of 200 kg (441 lb).
- Fasten the seat belt and lower the armrest.
- Start the engine.
- Disengage the parking brake.
- Run the engine at high idle with the speed and direction control in the HOLD position.
- Operate the tilt cylinders through at least five cycles. This will ensure that there is warm oil in the tilt cylinders.
- Tilt the bucket to the full TILT BACK position. Raise the bucket to the full RAISE position.
- Tilt the bucket from the full TILT BACK position to the full TILT FORWARD position. Record the time from the full TILT BACK position to the full TILT FORWARD position.
- Tilt the bucket from the full TILT FORWARD position to the full TILT BACK position. Record the time from the full TILT FORWARD position to the full TILT BACK position.
- Lower the bucket to the ground.
TRAVEL TIME (SPEED) FOR THE TILT CYLINDERS     | |
Position of the Work Tool Control     | 236/246     |
TILT FORWARD     | 2.0 ± 0.2 seconds     |
TILT BACK     | 1.6 ± 0.2 seconds     |
If the speeds are not correct, refer to the Testing and Adjusting, "Hydraulic System Troubleshooting".
Drift Check (Lift and Tilt Cylinder)
This procedure is done in order to determine the amount of wear that occurs in the lift cylinders and the tilt cylinders.
Note: Perform the following tests with a general purpose bucket on the machine. If a general purpose bucket is not available, use a load weight of 200 kg (441 lb).
- Run the engine at high idle.
- Operate the lift cylinders through at least five cycles. This will ensure that there is warm oil in the lift cylinder.
- Operate the tilt cylinders through at least five cycles. This will ensure that there is warm oil in the tilt cylinder.
- Raise the bucket to the full RAISE position.
- Tilt the bucket forward until the bucket is parallel with the ground.
- Reduce the engine speed to low idle. Stop the engine.
- Mark the cylinders.
- Use a stopwatch to count for one minute. Measure the drift of the cylinders.
Show/hide table
Table 3 CYLINDER DRIFT     Cylinders     Time     Cylinder Drift     Tilt Cylinders     1 minute     3 mm max     Lift Cylinders     1 minute     3 mm max     Note: If the lift cylinder drift and/or the tilt cylinder drift exceeds the maximum, refer to Testing and Adjusting, "Hydraulic System Troubleshooting" for probable causes.
- Start the engine and lower the bucket to the ground.