 |
|
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. |
| 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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products. Dispose of all fluids according to local regulations and mandates. |
| Pilot Oil Pressure | |||
|---|---|---|---|
| Date | Equipment ID Code | ||
| Pressure Specification | Actual | ||
| Low Idle | |
||
This test will check the pilot oil pressure reducing valve. Refer to the Systems Operation, Testing and Adjusting, "Machine Preparation for Troubleshooting".
| |
| Illustration 1 | g01623868 |
| Tool | Item | Part Number | Description | Qty |
|---|---|---|---|---|
| B | 198-4240 | Digital Pressure Indicator Gp | ||
| B1 | 198-4234 | Digital Indicator | 1 | |
| B2 | 251-9600 | Pressure Sensor Gp (0 to 68,900 kPa (0 to 10,000 psi)) | 1 | |
| B3 | 198-4236 | Adapter Cable As | 1 | |
- Bring the engine to normal operating temperature and move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel. Place the transmission direction control switch in the NEUTRAL position. Engage the parking brake. Lower the bowl to the ground. Retract the ejector cylinder and disengage the cushion hitch. Shut off the engine and turn the engine start switch to the ON position. Place chocks in front of the wheels and behind the wheels.
Show/hide table
NOTICE Perform the following steps prior to the pilot pressure diminishing. The procedure should be performed no more than 1/2 hour after the engine has been shut off.
- Move the control levers through the full range of travel. This movement of the levers will relieve any pressure that may be present in the hydraulic system. Turn the engine start switch to the OFF position.
- Slowly loosen the filler cap for the hydraulic oil tank in order to release the pressure
Show/hide table
Illustration 2 g03720509 Rear of the implement control valve
(1) Test port - Remove the dust cap from test port (1) and attach Tooling (B).
- Start the engine and run the engine at low idle.
- Put the bowl on the ground and lower the apron.
- Move the joystick control to the bowl RAISE position. The digital pressure indicator should read
3450 ± 345 kPa (500 ± 50 psi) .Note: The pilot oil pressure should also read
3450 ± 345 kPa (500 ± 50 psi) when the joystick control is in any of the following positions:- Bowl LOWER position
- Bowl RAISE position
- Ejector FORWARD position
- Ejector REVERSE position
- Apron RAISE position
- Apron LOWER position
- Remove the test equipment.
- If adjustment of the pressure reducing valve is necessary, then loosen nut (3) and use an allen wrench to turn adjustment screw (4).
Note: One turn of the adjustment screw changes the pressure by approximately
310 kPa (45 psi) .
| |
| Illustration 3 | g03720595 |
|
Pilot control manifold (2) Pressure reducing valve (3) Nut (4) Adjustment screw | |