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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, 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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Sudden movement or accidental starting of the machine can cause personal injury or death to persons on or near the machine. To prevent personal injury or death, perform the following: Park the machine on a smooth, level surface. Lower the work tool to the ground and engage the parking brake. Stop the engine and remove the key. Block the wheels and install the steering frame lock. |
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Personal injury or death can result from sudden movement of the lift cylinders or the tilt cylinders. Do not stand under the work tool when you are testing or adjusting the lift cylinders or the tilt cylinders. Do not stand under the lift arms when you are testing or adjusting the lift cylinders or the tilt cylinders. |
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| NOTICE |
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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, "AVSpare Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on AVSpare products. Dispose of all fluids according to local regulations and mandates. |
| Required Tools | ||
| Part Number | Description | Qty |
| 6V-9832 | Cap | 1 |
| 6V-9511 | Face Seal Plug | 1 |
| 6V-9746 | O-Ring Seal | 1 |
An initial test for tilt cylinder drift should be completed before performing the isolation test on the tilt cylinders.
Reference: For more information on testing the machine for drift, refer to the Troubleshooting, RENR6221, "Lift and Tilt Cylinder Drift - Check".
This test will help to determine whether one of the tilt cylinders is causing a drift problem. This test will also help determine the component that is causing the drift. Perform this test with an empty work tool. When the hose at the rod end of the tilt cylinder is blocked, the tilt cylinder should not move during the drift test. If the tilt cylinder drifts, the internal leakage is probably in one of the tilt cylinders. If the drift test for the tilt cylinders is within the specification, the problem is probably in the main control valve.
Machine Preparation for Troubleshooting
- Park the machine on a smooth, level surface. Move away from working machines and personnel. Lower the work tool to the ground.
- Allow only one operator on the machine. Keep all personnel away from the machine or in the view of the operator.
- Ensure that the transmission is in the NEUTRAL position. Engage the parking brake.
- Place the steering frame lock in the LOCKED position.
Isolation Test for the Tilt Function
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| Illustration 1 | g00929401 |
Top View of the Loader Frame | |
| Maximum Drift For The Tilt Cylinder | ||
| Oil Temperature | Time | Distance |
| Less than 50 °C (120 °F) |
5 Minutes | 19 mm (0.750 inch) |
50 °C (120 °F) to 65 °C (150 °F) |
2.7 Minutes | 19 mm (0.750 inch) |
| Greater than 65 °C (150 °F) |
1.7 Minutes | 19 mm (0.750 inch) |
- Start the engine. Move the tilt cylinders to full travel at least five times in order to warm the hydraulic oil to normal operating temperature. Normal operating temperature is between 54 °C (130 °F) and 82 °C (180 °F).
- Position the work tool on the ground and turn the engine start switch to the OFF position.
- Release the pressure in the hydraulic system.
Reference: Refer to the Service Manual module Testing and Adjusting, "System Pressure Release" for the machine that is being serviced.
- After the hydraulic pressure has been released, clean the fitting for the hose assembly before disassembly. Remove the hose assembly that is shown by the arrow from the tube assembly. Hold up the hose assembly. Ensure that the hose assembly is full of hydraulic oil. Install a 6V-9511 Face Seal Plug and a 6V-9746 O-Ring Seal in the hose that connects to the head end of the tilt cylinder. Install a 6V-9832 Cap on the tube assembly. Tighten the plug and tighten the cap.
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| Illustration 2 | g00930783 |
Location of the Hydraulic Hose for the Drift Test | |
- Start the engine. Run the engine at low idle.
- Raise the bucket off the ground to approximately 1 m (3.3 ft).
- Place the lift control lever into the HOLD position.
- Turn the engine start switch to the OFF position.
- Mark the cylinder rod. This will be an initial position for the measurement.
- Place the tilt control lever into the DUMP position. Measure the distance of rod movement for the left tilt cylinder. Refer to Table 2 for the maximum drift for the period of time at the given temperature.
If the isolation test is within the specifications, the tilt cylinder is not the cause. If there is too much drift, the tilt cylinder has an internal leak. Look for a scored cylinder or a damaged piston seal.
- Start the engine. Lower the work tool to the ground.
- Turn the engine start switch to the OFF position.
- Release the pressure from the hydraulic system.
Reference: Refer to the Service Manual module Testing and Adjusting, "System Pressure Release" for the machine that is being serviced.
- After the hydraulic pressure has been released, remove 6V-9511 Face Seal Plug and a 6V-9746 O-Ring Seal from the hose end of the lift cylinder. Remove 6V-9832 Cap from the tube assembly. Connect the hose assembly to the tube assembly. Tighten the hose assembly. Proceed to Step 15.
- Clean the fitting for the hose assembly before disassembly. Remove one hose assembly that is shown by the arrow from the tube assembly on the right side of the machine. Hold up the hose assembly. Ensure that the hose assembly is full of hydraulic oil. Install a 6V-9512 Face Seal Plug and a 5K-9090 O-Ring Seal in the hose that connects to the head end of the tilt cylinder. Install a 6V-9833 Flared Cap on the tube assembly. Tighten the plug and tighten the cap.
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| Illustration 3 | g00930796 |
Location of the Hydraulic Hose for the Drift Test | |
- Repeat Step 5 through Step 12 in order to isolate tilt cylinder drift for the other cylinder.
If the isolation test is within the specifications, the tilt cylinder is not the cause. If there is too much drift, the tilt cylinder has an internal leak. Look for a scored cylinder or a damaged piston seal.
- Release the pressure from the hydraulic system.
Reference: For more information about releasing the pressure in the hydraulic system, refer to the Service Manual module Testing and Adjusting, "System Pressure Release" for the machine that is being serviced.
- After the hydraulic pressure has been released, remove 6V-9511 Face Seal Plug and a 6V-9746 O-Ring Seal from the hose end of the lift cylinder. Remove 6V-9832 Cap from the tube assembly. Connect the hose assembly to the tube assembly. Tighten the hose assembly.
- Place the steering frame lock in the STORE position.