Release Procedure
| Required Tools | |||
|---|---|---|---|
| Tool | Part Number | Part Description | Qty |
| A | 177-7861 | Hose As | 1 |
| 6V-4143 | Couplers | 2 | |
| 8T-0860 | Pressure Gauge (0 to 40,000-kPa (0 to 5,800-psi)) | 1 | |
Note: Permit only one operator on the machine. Keep all other personnel away from the machine or in the operators sight.
| NOTICE |
|---|
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, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates. |
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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 work tools have been lowered to the ground, and the 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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- Move the machine to a hard level surface that is away from operating machines and away from personnel.
- Place the transmission direction and speed control in the NEUTRAL position and in any speed position. Engage the steering and transmission lock control.
- Engage the parking brake. Place wheel blocks in front of the wheels and behind the wheels.
- When the bucket and/or attachment is raised for testing or for adjusting, make sure that the bucket and/or attachment is supported correctly. Also, make sure that the bucket and/or attachment is fully in the DUMP position. The lift circuit has high oil pressure when the lift arms raise the front of the machine.
Note: Do not stop the machine with the front of the machine off the ground unless this is required for a test. Lower the machine to the ground and stop the engine.
- If the machine is equipped with an optional ride control system, with the engine speed above 1500 rpm, press and hold the ride control switch to the SERVICE position. Move the joystick control lever to the FLOAT position. This will relieve all of the hydraulic pressure in the ride control accumulator.
- Decrease the engine speed to low idle.
- Stop the engine.
- Refer to Disassembly and Assembly, "Steering Frame Lock - Remove and Install".
- Move the joystick control lever through the full range of travel. This will relieve any pressure that may be present in the implement hydraulic system.
- Move the STIC steering control several times in both directions to release the pressure in the steering system.
- Depress the brake pedal at least 25 times to release any pressure in the braking system.
- Depress the breaker relief valve on the hydraulic tank to release the pressure in the hydraulic tank.
- Connect Tooling (A) to pressure tap (1). If there is any pressure on the gauge, move the joystick control lever to all positions until all the pressure is removed from the system.
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| Illustration 1 | g00975402 |
(1) Pressure tap (for the rod end of the tilt cylinder) (2) Pressure tap (for the head end of the tilt cylinder) | |
- Connect Tooling (A) to pressure tap (2). If there is any pressure on the gauge, move the joystick control lever to all positions until all the pressure is removed from the system.
- The pressure in the hydraulic system has now been released. The lines, fittings and components can be removed.
- Remove the test equipment.