PISTON 9W4452 - Caterpillar

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.
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.
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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Note: Permit only one operator on the machine. Keep all other personnel away from the machine or in view of the operator.
Move the machine to a smooth, level location that is away from operating machines and away from personnel.
Engage the parking brake. Place wheel blocks in front and behind the wheels or tracks.
Lower the work tool to the ground.
Stop the engine.
Make sure that all hydraulic oil pressure is released before performing any maintenance on the machine. Refer to Operation and Maintenance Manual , "System Pressure Release" for more information.Perform a visual inspection first. If the visual checks are completed but the problem has not been identified, perform operational checks. If the problem has not been identified, perform instrument tests. This procedure will help to identify system problems.