VALVE AS-RELIEF 1739887 - Caterpillar

Personal injury or death can result from sudden machine movement.Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.To help prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic and steering system:
Check valves in the hydraulic system may allow pressure to exist in the hydraulic lines after the engine has been stopped. Pressure must be relieved prior to servicing the components of the hydraulic system. Failure to relieve pressure prior to servicing may result in personal injury.
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.
Move the machine to a smooth horizontal location. Move away from operating machines and move away from all personnel. Lower all implements to the ground. Place the joystick control for the blade lift control valve in the FLOAT position.
Install the wheel lean locking bolt in the front axle. Install the frame lock pin. Engage the parking brake and stop the engine.
Permit only one operator on the machine. Keep all other personnel away from the machine. Also, all personnel should be visible to the operator.
Place chocks in front of the wheels and behind the wheels.
Make sure that all hydraulic pressure is released before you perform any of the following procedures:
Loosen any fitting, any hose, or any component.
Tighten any fitting, any hose, or any component.
Remove any fitting, any hose, or any component.
Adjust any fitting, any hose, or any component.
After the pressure in the system has been released, carefully loosen fittings and remove lines or components.