COIL AS 4178521 - Caterpillar

Hot oil and hot components can cause personal injury. Do not allow hot oil or hot components to contact the skin.
Personal injury or death can result from escaping fluid under pressure.Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.In order to prevent possible injury, perform the following procedure before testing and adjusting any of the machine hydraulic systems.
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, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
When you are analyzing a hydraulic system for poor performance, remember that correct oil flow and correct oil pressure are necessary for correct operation. Oil flow is a function of the pump output. The pump output is a function of engine speed. A restriction to the flow of oil causes oil pressure.For any test to the hydraulic system, the hydraulic oil must be at the normal operating temperature. To increase the oil temperature, start the engine. Move the body several times. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark on the temperature gauge.Before any tests are performed, visually inspect the complete hydraulic system for oil leaks and for damaged parts. For some of the tests, a magnet and a measuring rule (inches or millimeters) may be used.Note: Permit only one operator on the machine. Keep all other personnel away from the machine or in the operator's sight.
Move the machine to a smooth, horizontal location. Move away from operating machines and away from other personnel.
Move the transmission control to the NEUTRAL position.
Engage the parking brake.
Install the steering frame lock.
Put wheel blocks in front of the wheels and behind the wheels.
If it is necessary to raise the dump body of the truck, install the body retaining pins.
If it is necessary to work around the tailgate, install the tailgate retaining pins.
Move the hoist control lever to the HOLD position.
Stop the engine.
Depress the brake pedal at least 70 times to remove the oil pressure from the brake accumulators.
Depress the breaker relief valve on the hydraulic tank to release the pressure in the hydraulic tank.
Make sure that all oil pressure is released before any fitting, hose or component is loosened, tightened, removed, or adjusted.