| Required Tools | ||
| Part Number | Description | Qty |
| 4C-6500 | Digital Thermometer | 1 |
| 4C-4892 | ORFS Fittings Group | 1 |
| 9U-7400 | Multitach | 1 |
 |
Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury to persons on or near the machine. To prevent injury or death, make sure that the area around the machine is clear of personnel and obstructions before operating the machine. |
 |
| 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. |
| NOTICE |
|---|
To avoid damage to the vibratory system during testing, always perform the testing with the vibratory drum on top of tires or on loose dirt. Tires will simulate a non-compacted soil condition. Never operate the vibratory system when the machine is on concrete. |
| NOTICE |
|---|
If a testing time longer than three (3) minutes is required, rotate the drum periodically in order to lubricate the eccentric weight shaft bearings. |
Note: The hydraulic oil temperature should be at least 38°C (100°F).
Note: Two separate charge pressures are measured during this test. The following procedure measures the charge pressure after the charge filter, when the propel control lever is in the STOP position and when the vibratory system is OFF. The second pressure measures the charge pressure after the charge filter, when the propel control lever is in the STOP position and when the vibratory system is ON.
Vibratory System OFF
- Stop the machine and apply the parking brake.
- Install a 4134 kPa (600 psi) pressure gauge at the charge pressure test port (1) which is located after vibratory charge filter (2) .
 | |
| Illustration 1 | g00460687 |
Left Side of Machine (1) Charge pressure test port. (2) Charge filter. | |
- Install the multitach in order to measure the engine rpm.
- Install 4C-6500 Digital Thermometer into the hydraulic oil tank.
- Start the machine and run the machine at high idle (2350 ± 50 RPM) until the hydraulic oil temperature reaches 38°C (100°F).
- Read the charge pressure at pressure test port (1). Charge pressure (NEUTRAL) should be 2950 ± 150 kPa (428 ± 22 psi).
- To increase the charge pressure in NEUTRAL, add shims to the relief valve. Remove shims from the relief valve in order to decrease the charge pressure.
Note: Determine the condition of the charge filter before any adjustments are made. This affects the charge pressure. Nominal stack height of the shims for the charge relief valve is 3.04 mm (.120 inch).
 | |
| Illustration 2 | g00460734 |
Vibratory Pump (3) Screw For The Adjustment Of The Charge Pressure. | |
- Once Step 7 is complete, tighten the locknut to a torque of 50 ± 5 N·m (37 ± 4 lb ft).
- Recheck the charge pressure. Once the vibratory charge pressure is correct, proceed to "Vibratory System ON".
Vibratory System ON
 | |
| Illustration 3 | g00610458 |
Control Console (4) Amplitude selector. | |
- Place the amplitude selector (4) in the LOW AMPLITUDE position.
- With the engine at high idle (2350 ± 50 RPM), activate the vibratory system. Observe the vibratory charge pressure at pressure test port (1). The vibratory charge pressure should be 130 ± 70 kPa (19 ± 10 psi) lower than the normal operating pressure that was measured in "Vibratory System OFF".
- Place the amplitude selector (4) in the HIGH AMPLITUDE position. Repeat Step 2 again. The charge pressure should have the same value. This step verifies the movement of the spool in the flushing valve.
- Stop the vibratory system and stop the engine. Remove all tooling.
Note: The vibratory charge pressure is controlled by the flushing valve which is located in the motor. If the charge pressure at test port (1) does not decrease from the pressure that was recorded in "Vibratory System OFF", a problem may exist with the flushing valve and/or the adjustment of the charge relief valve. The vibratory charge pressure should be 130 ± 70 kPa (19 ± 10 psi) lower than the pressure that was recorded in "Vibratory System OFF". If the pressure decreases too much, excessive case leakage may exist or the flushing valve may be improperly shimmed. The nominal stack height of the shims should be 6.5 mm (0.26 inch). The Testing and Adjusting Vibratory Motor Case Drain Flow - Test and Adjust should be performed if the charge pressure is too low.