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Injury to personnel can result if they are not in the operator's view. Allow only essential personnel near the machine, and make sure the personnel are in the operator's view when testing, to prevent injury. Make sure checks are done in an open area. |
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Before performing operational checks, refer to Testing and Adjusting, "Machine Preparation for Troubleshooting" and Testing and Adjusting, "Visual Inspection".
Steering Time
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Personal injury or death can result from sudden machine movement. Personnel can be injured during the steering check. To help prevent possible personal injury, keep all personnel away from the machine or in clear view of the operator when the machine is in operation during steering checks. |
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Note: Measuring the steering time will determine if there is a reason to check the priority valve or the metering pump.
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel.
- Place the direction control switch (1) in the NEUTRAL position.
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| Illustration 1 | g01061827 |
(1) Direction control switch | |
- Engage the parking brake (2) .
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| Illustration 2 | g01061822 |
(2) Parking brake control | |
- Raise the work tool slightly off the ground.
- Run the engine at high idle.
- Turn the machine to the left until the stop (3) contacts the stop pad (4) .
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| Illustration 3 | g01061820 |
(3) Stop (4) Stop pad | |
- Turn the machine fully to the right. Record the time for a full turn from the left stop to the right stop. The time for a full turn from the left stop to the right stop should be 6.4 ± 1.0 seconds. If the time is higher, refer to Testing and Adjusting, "Steering System Troubleshooting".
- Turn the machine fully to the left. Record the time for a full turn from the right stop to the left stop. The time for a full turn from the right stop to the left stop should be 5.6 ± 1.0 seconds. If the time is higher, refer to Testing and Adjusting, "Steering System Troubleshooting".
Cylinder Speed Check
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Personal injury or death can result from machine articulation or movement. Machine frames can move and a person can be crushed. Connect the steering frame lock link between the front and rear frames before working on machine. |
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Lift Cylinder
Note: Perform the cylinder speed check with an empty general purpose bucket.
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel.
- Move the direction control switch to the NEUTRAL position.
- Lower the bucket to the ground. Stop the engine.
- Engage the parking brake.
- Connect the steering frame lock.
- Start the engine and warm the hydraulic oil to 60° ± 5°C (140° ± 9°F).
- Run the engine at high idle.
- Operate the lift cylinder through five cycles. This will ensure that there is warm oil in the lift cylinder.
- 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 to the full RAISE position. Record the time from the full LOWER position to the full RAISE position.
- Lower the bucket from the full RAISE position to the full LOWER position. Record the time from the full RAISE position to the full LOWER position.
| Travel Time (Speed) for the Lift Cylinder | ||
| Function | 906 | 908 |
| Full LOWER position to the full RAISE position | 3.9 ± 0.3 seconds | 4.3 ± 0.3 seconds |
| Full RAISE position to the full LOWER position | 3.6 ± 0.5 seconds | 2.8 ± 0.5 seconds |
If the speeds are not correct, check the following conditions:
- Check the pressure settings of the main relief valve and the line relief valve.
- Check the flow of the work tool pump. Refer to Testing and Adjusting, "Pump Flow - Test".
- Check the valve spool in the lift control valve.
- Check the piston seals in the lift cylinder.
Tilt Cylinder
Note: Perform the cylinder speed check with an empty general purpose bucket.
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel.
- Move the direction control switch to the NEUTRAL position.
- Lower the bucket to the ground. Stop the engine.
- Engage the parking brake.
- Connect the steering frame lock.
- Start the engine and warm the hydraulic oil to 60° ± 5°C (140° ± 9°F).
- Run the engine at high idle.
- Raise the bucket to full RAISE.
- Operate the tilt cylinder through five cycles. This will ensure that there is warm oil in the tilt cylinder.
- Tilt the bucket to the full TILT BACK position.
- Tilt the bucket from the full TILT BACK position to the full DUMP position. Record the time from the full TILT BACK position to the full DUMP position.
- Tilt the bucket from the full DUMP position to the full TILT BACK position. Record the time from the full DUMP position to the full TILT BACK position.
| Travel Time (Speed) for the Tilt Cylinder | ||
| Function | 906 | 908 |
| Full TILT BACK position to the full DUMP position | 1.6 ± 0.3 seconds | 1.6 ± 0.3 seconds |
| Full DUMP position to the full TILT BACK position | 1.9 ± 0.3 seconds | 1.9 ± 0.3 seconds |
If the speeds are not correct, check the following conditions:
- Check the pressure settings of the main relief valve and the line relief valve.
- Check the flow of the work tool pump. Refer to Testing and Adjusting, "Pump Flow - Test".
- Check the valve spool in the tilt control valve.
- Check the piston seals in the tilt cylinder.
Cylinder Drift Test
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Personal injury or death can result from machine articulation or movement. Machine frames can move and a person can be crushed. Connect the steering frame lock link between the front and rear frames before working on machine. |
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Note: Perform the check for the lift cylinder drift and the tilt cylinder drift with an empty general purpose bucket.
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel.
- Move the direction control switch to the NEUTRAL position.
- Lower the bucket to the ground. Stop the engine.
- Engage the parking brake.
- Place chocks in front of the wheels and behind the wheels.
- Connect the steering frame lock.
- Start the engine and warm the hydraulic oil to 60° ± 5°C (140° ± 9°F).
- Run the engine at high idle.
- Operate the lift cylinder through five cycles. This will ensure that there is warm oil in the lift cylinder.
- Operate the tilt cylinder through five cycles. This will ensure that there is warm oil in the tilt cylinder.
- Raise the bucket to the full RAISE.
- Tilt the bucket until the bucket is parallel with the ground.
- Reduce the engine speed to low idle. Stop the engine.
- Measure the amount of rod movement in three minutes. The maximum rod movement in the lift cylinder and in the tilt cylinder should not exceed 15 mm (0.6 inch).
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.
- Lower the bucket to the ground.
- Stop the engine.
- Remove the chocks.
- Disconnect the steering frame lock.