For any test to the steering hydraulic system, the hydraulic oil must be at the normal operating temperature. To increase the oil temperature, start the engine. Run the engine at high idle. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark.
Before any tests are performed, visually inspect the complete steering system for oil leaks and for damaged parts. For some of the tests, a magnet and a measuring rule (inches or millimeters) may be used.
 |
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 steering system. |
 |
|
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 hydraulic system. |
|
|
Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak. |
|
|
At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin. Before installation or removal of any hydraulic test equipment, relieve the pressure in the hydraulic tank by slowly loosening the filler cap. |
|
| 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 Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates. |
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel.
- Permit only one operator on the machine. Keep all other personnel away from the machine or in sight of the operator.
- Place the transmission direction control switch in the NEUTRAL position.
- Engage the parking brake. Put blocks in front of the wheels and behind the wheels.
- Lower the decking blade and the grapple to the ground.
- Install steering frame lock (1) in the LOCKED position.
 | |
| Illustration 1 | g00616435 |
Steering Frame Lock (1) Steering frame lock in the LOCKED position. | |
- Stop the engine.
- Turn the engine start switch key to the OFF position.
- Move the implement control levers through the full range of travel. This will relieve any pressure that may be present in the implement hydraulic system.
- Depress the brake pedal repeatedly. This will relieve any pressure that may be present in the brake hydraulic system.
- Turn the steering wheel several times in both directions in order to release the pressure in the steering system.
- In order to relieve all of the pressure in the hydraulic oil tank, open the access door on the top of the engine enclosure. Carefully loosen filler cap (2) on the hydraulic tank in order to release the pressure in the tank.
 | |
| Illustration 2 | g00713275 |
Hydraulic Tank (Earlier Models) (2) Filler cap. | |
 | |
| Illustration 3 | g00887559 |
Hydraulic Tank (Newer Models) (2) Filler cap. | |
- Make sure that all oil pressure is released before you begin any work on the steering hydraulic system.
- The pressure in the hydraulic system has been released. Hose assemblies, tube assemblies, and components can be removed.