ENGINE AR 1078762 - Caterpillar

Table 1
Required Tools    
8T0855     Pressure Gauge 4000kPa (600 psi)     1    
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 vibratory system.
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.
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.
Illustration 1 g00570800
Pressure Test For The Vibratory Valve (1) Vibratory pump. (2) Charge relief valve. (3) Pressure tap. (4) Vibratory valve.
Use the following procedure before you perform the testing and adjusting:
Apply the parking brake.
Place the speed/direction control lever in neutral.
Connect the pressure gauge to the pressure tap (3). This is marked "CP" on the vibratory valve (4) .
Start the engine. Operate the engine at high idle 2325 25 rpm. Record the pressure gauge reading. The pressure setting for the charge relief valve should be 2500 140 kPa (363 20 psi).
If the pressure setting for the charge relief valve is not correct, the pressure must be adjusted. Loosen the locknut. Use an allen wrench and turn the adjustment screw clockwise in order to increase the pressure. Turn the adjustment screw counterclockwise in order to decrease the pressure.
After the pressure for the charge relief valve is adjusted, tighten the locknut. Decrease the RPM of the engine to the low idle position and recheck the pressure. The pressure should be greater than 2060 kPa (299 psi). After the pressure for the charge relief valve has been rechecked, remove the pressure gauge from the pressure tap (3) .