VALVE GP-RELIEF 6E6293 - Caterpillar

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 power train.
Before you perform these procedures, refer to Testing and Adjusting, "Machine Preparation" for the correct procedure for machine preparation.The following operational checks can be used for the following items:
find leakage in the system.
determine whether the joystick controls are functioning correctly.
determine whether the pump or motors are functioning correctly.
determine whether the whole work tool system is functioning correctly.In order for the hydraulic system to function properly, each component in the system must be set to the correct specifications. Some components must be set prior to the testing of other components. A component that is not set properly will have an impact on other components in the system.Note: The oil in the hydraulic system must be at an operating temperature range of 50° 10°C (122° 18°F). In order to increase the oil temperature, start the engine and operate all the cylinders for at least five cycles. Also, drive the machine forward and drive the machine rearward.Lift Cylinder Speed Test
Note: Perform the lift cylinder speed test with an empty general purpose bucket. If a general purpose bucket is not available, then use a load weight of 200 kg (441 lb).
Fasten the seat belt and lower the armrest.
Start the engine.
Disengage the parking brake.
Run the engine at high idle with the speed and direction control in the HOLD position.
Operate the lift cylinder through at least five lift cycles. This will ensure that there is warm oil in the lift cylinders.
Tilt the bucket to the full TILT BACK position. Lower the bucket to the full LOWER position.
Raise the bucket from the full LOWER position. Record the time from the full LOWER position to the full RAISE position.
Lower the bucket from the full RAISE position. Record the time from the full RAISE position to the full LOWER position.
Raise the bucket to the full RAISE position. Move the work tool control to the FLOAT position. Record the time from the full RAISE position to the full LOWER position.
Table 1
TRAVEL TIME (SPEED) FOR THE LIFT CYLINDERS    
Position of the Work Tool Control     236/246    
RAISE     2.7 0.2 seconds    
LOWER     2.7 0.2 seconds    
FLOAT     2.8 0.2 seconds    If the speeds are not correct, refer to the Testing and Adjusting, "Hydraulic System Troubleshooting".Tilt Cylinder Speed Test
Note: Perform the tilt cylinder speed test with an empty general purpose bucket. If a general purpose bucket is not available, then use a load weight of 200 kg (441 lb).
Fasten the seat belt and lower the armrest.
Start the engine.
Disengage the parking brake.
Run the engine at high idle with the speed and direction control in the HOLD position.
Operate the tilt cylinders through at least five cycles. This will ensure that there is warm oil in the tilt cylinders.
Tilt the bucket to the full TILT BACK