SHIELD 0017442 - Caterpillar

Operation Checks
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.
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 work tools have been lowered to the ground, and the 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.
The operation checks can be used to find leakage in the system and the operation checks can analyze the overall performance of the machine. The checks can be used to determine whether the solenoids for the servo valve are functioning properly. The checks can also be used to determine whether the pump or the motor is functioning properly.The oil in the hydraulic system must be at an operating temperature of 40 to 55°C (104 to 131°F).The crossover relief valves and the POR valve are specific to the winch circuit. The winch circuit operates independently from other circuits.The winch functions are controlled by pulse width modulation signals that are sent from the electronic control module. The electronic control module sends a signal to the solenoid valve. As the solenoid shifts, the servo valve shifts. This action will allow the pilot oil to shift the actuator piston. The actuator piston can cause the pump to upstroke and the actuator piston can cause the pump to destroke. The winch piston pump's charge circuit provides charge oil to the drive circuit of the winch. The charge pump provides cooling oil and flushing oil to the drive circuit of the winch. The charge circuit from the front piston pump provides signal oil to the winch brake.Designation of the Remote Pressure Taps
Illustration 1 g01424980
Table 1
Designation Of The Remote Pressure Taps    
Number of the Pressure Tap    Description    
1     Right Drive Loop Pressure    
2     Left Drive Loop Pressure    
3     Front Charge Pressure    
4     Rear Charge Pressure    
5     Winch Charge Pressure    Use Table 1 to identify the remote pressure taps in Illustration 1.