Hydraulic System Fluid Leak
A Boeing 777 has a hydraulic system leak in the right engine driven pump (EDP) system. The system uses Skydrol hydraulic fluid. The leak is identified at a flare fitting on a pressure line. The maintenance manual specifies a torque value of 135 lb-in for the fitting. The AME must repair the leak and ensure the system is serviceable. The aircraft has three hydraulic systems: left, right, and center. The right system powers the right engine thrust reverser and some flight controls.
1. What are the steps to repair the leak and return the system to service?
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- Depressurize the right hydraulic system. 2) Drain fluid from the affected line. 3) Disconnect the flare fitting, inspect for damage or contamination. 4) Replace the fitting if damaged, or clean and reassemble with new seals if required. 5) Torque the fitting to 135 lb-in using a calibrated torque wrench. 6) Refill the system with Skydrol and bleed air from the lines. 7) Pressurize and check for leaks. 8) Perform operational test of affected components.
2. Explain the precautions for working with Skydrol hydraulic fluid.
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Skydrol is a phosphate ester-based fluid that can cause skin irritation and damage to paint. Precautions: wear protective gloves, goggles, and clothing. Avoid contact with skin and eyes. Use in well-ventilated area. Clean spills with absorbent material and dispose of properly. Do not mix with other fluids. Ensure no contamination with water or petroleum products.