TUBE AS-TURBOCHARGER OIL 2W7762 - Caterpillar

When the oil in the power train gets hot, it causes the air to expand and build up pressure in the power train oil tank.Pressure can remain in the power train oil tank after the engine and pumps are stopped.Personal injury can occur if pressure is not released before any service is performed on the power train.To prevent possible injury, remove the cap from the oil filler tube before any fitting, hose, or component in the power train is loosened, tightened, removed, and/or adjusted.The cap must be replaced when the tests and/or the adjustments are completed.The bucket and the other attachments must always be flat on the ground before service is performed.When it is necessary for an attachment to be raised while tests and/or adjustments are being performed, be sure the correct supports are in place. In the case of the bucket, it must be in the full DUMP position.Move the machine to a location away from the travel of other machines.Wear the seat belt, and be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being performed.
Procedure
When you are defining a power train problem or a hydrostatic transmission problem, use the following procedure.First, perform Visual Checks. Next, perform the Operation Checks and verify the symptom.Lastly, perform the Instrument Tests if the cause of the problem has not been found.Once the problem is defined, proceed to Troubleshooting. Since there may be more than one cause for a particular problem, the Troubleshooting section may suggest specific instructions. The Troubleshooting section may also suggest the performance of instrument tests.These inspections and these tests aid in determining the most probable cause.The list cannot give all possible problems and all possible corrections. The service personnel must find the problem and the source. Then, the service personnel must make the necessary repairs.During the diagnosis of a problem in the power train or in the hydrostatic transmission, remember that correct oil flow, correct temperature, and correct pressure are necessary for proper operation.The pumps create oil flow. Oil pressure is caused by resistance to the oil flow. Oil sump temperature must be a minimum of 52.0 °C (125.6 °F) during diagnosis.
Do not stall the implements during hydraulic system warm-up. Stalling the implements causes oil to flow across the relief valve. This can damage the vane-type hydraulic pump when the system is cold. Before you allow the implements to stall, wait until the hydraulic system reaches operating temperature.
When more checks are necessary, use the appropriate hydraulic gauges or the 131-5051 DataView Group .Finding the solution to a problem can be made easier if the following information is known:
The performance of the system decreases rapidly if the level of the oil in the hydraulic tank is not within specifications. Also, the performance of the system decreases rapidly if the viscosity of the oil in the hydraulic system is not in accordance with specifications.
If the oil level is too low, the unit can malfunction completely.
Oil that is too