CYLINDER GP-LIFT 2496711 - Caterpillar

At operating temperature, the hydraulic oil is hot and under pressure. Hot oils can cause burns.To prevent possible personal injury, release the pressure in the work tool hydraulic circuit (boom, stick, bucket, and swing), travel circuits, and the hydraulic oil tank at the filler cap before any hydraulic lines or components are disconnected or removed.Remove the filler cap only when the engine is stopped and the filler cap is cool enough to touch.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Dispose of all fluids according to local regulations.
Table 1
Required Tools    
Tool    Part Number    Part Description    Qty    
A     4C-4892     ORFS Fittings Group     1    
8T-0859 Pressure Gauge
(1)
25000 kPa (3620 psi)     1    
( 1 ) Part of 4C-4892 ORFS Fittings Group
Inspect the rotate circuit for external leakage. If a leak is found, perform the necessary repairs. If there is no sign of leakage, proceed to the next step.
Check each control valve for the proper operating pressure. Refer to Service Manual, "Control Valve Pressure (Hydraulic Rotator) - Test". The control valve must be operating at the proper pressure in order for this test to be valid.
Adjust the pressure of the host machine for the rotate circuit to 12000 500 kPa (1740 70 psi). Refer to Service Manual for the host machine for the adjustment procedure.
Illustration 1 g01894255
(CW) Rotate circuit clockwise and (CCW) Rotate circuit counterclockwise
Illustration 2 g01894315
Remove hose assembly (1) from the work tool. Plug the hose from the machine. Cap the coupling on the work tool. This will prevent oil from returning to the hydraulic tank.
Install Tooling (A) on test fitting (2) for the return side of the circuit.
Start the engine of the host machine and operate the machine until the hydraulic oil reaches normal operating temperature.
Open the jaws of the work tool. In order to prevent rotation, rotate the work tool to a horizontal position. Place the work tool on the ground. Place downward pressure on the work tool in order to prevent the work tool from rotating.
Attempt to rotate the work tool in a counterclockwise direction. Record the reading on the pressure gauge.
If the pressure on the pressure gauge increases, the gerotor motor must be repaired. Refer to Service Manual, "Gerotor Motor - Disassemble".
The air must be purged from the work tool before the tool is returned to operation. Refer to Service Manual, "Hydraulic System Air - Purge" for the proper procedure.