PUMP AS-COOLANT 4P5140 - Caterpillar

Machine Preparation
Sudden movement of the machine or release of oil under pressure can cause serious injury to persons on or near the machine.To prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic system.
Move the machine to a smooth horizontal location. Move away from working machines and personnel. Lower implements and lower the three-point hitch to the ground.
Permit only one operator on the machine. Keep other service personnel in the view of the operator or away from the machine.
Engage the parking brake.
Turn off the engine.
Move the control levers to all positions in order to release the pressure in the implement hydraulic system.
Move the steering wheel to the right and move the steering wheel to the left in order to release the pressure in the steering hydraulic system.
Make sure that all hydraulic pressure is released before any fittings, any hoses, or any components are loosened, tightened, removed, or adjusted.
The pressure in the system has now been released. Lines and components can be removed.Procedure
When you are defining a problem in the implement, steering and brake hydraulic systems, the following procedure should be followed. Perform the visual checks in Testing and Adjusting, "Visual Inspection". If you complete the visual Inspection and the problem is not identified, perform the operation checks. If you complete the operation checks and the problem is not identified, perform the instrument tests.This procedure can help identify problems in the implement, steering and brake hydraulic systems. When the problem is defined, refer to Testing and Adjusting, "Troubleshooting". The troubleshooting section lists the probable causes of a known problem. Since more than one cause may exist for a problem, the troubleshooting section may suggest specific inspections or instrument tests. These inspections and tests will help identify the most probable cause.Note: During a diagnosis of the implement, steering and brake hydraulic systems, remember that correct oil flow and pressure are necessary for correct operation. Oil pressure is caused by resistance to the flow of oil. Oil temperature must be a minimum of 60 °C (140 °F).Refer to the Testing and Adjusting, "Troubleshooting" for the location and for the correction of problems that are in the implement, steering and brake hydraulic systems.Troubleshooting Procedure
There are six steps to troubleshooting:
Know the machine.
Understand the symptom.
Verify the symptom.
Determine the probable causes.
Reduce the list of probable causes.
Test the system.Use these steps to troubleshoot this machine.Know the Machine
Understand the operation of the machine. Know if the symptom is a characteristic of normal operation or if the symptom is a failure.Read the systems operation information in order to understand the systems of the machine. You must understand the interaction of the machine systems.Understand the Symptom
You need to speak with the operator about the symptom.
Ask about the performance of the machine prior to the failure.
Determine the time of the first occurrence of the symptoms.
Determine the operating conditions at the time of the failure.
Ask the operator about the sequence of events prior to the failure. Determine the order of the occurrences.
Ask the operator about the steps