Biweekly Inspection The biweekly inspection includes all the tasks of the weekly inspection and the following additional tasks: 1. Inspect the pump drive belt for proper tension, pulley alignment, excessive belt wear, and tightness of pulley setscrews. 2. Perform the orifice calibration check in accordance with AVAIR 13-1-6.4. 3. Perform the flowmeter intercomparison test in accordance with NAVAIR 13-1-6.4. Monthly Inspection The monthly inspection includes all the tasks of the biweekly inspection and the following ad- ditional tasks: 1. Inspect the N₂ and air inlet connectors for dirt, foreign matter, corrosion, stripped threads, and badly scared surfaces. 2. Inspect the gaskets at bulkhead fittings and vacuum pump filters for deterioration and proper fits and alignments. 3. Inspect the copper tubing for corrosion and tightness of soldered joints. 4. Inspect the altitude chamber for clean- liness, proper fit and alignment of gaskets, excessive scratches on chamber door, leaks or corrosion at pipe fittings, and wear of the door gasket. 5. Inspect all tubing and piping for tightness and proper alignment. 6. Inspect all electrical plugs, connectors, and wiring for physical damage, bent pins, loose connections, and security of cables. 7. Inspect all control valves for cleanliness and tightness of mounting nuts and knobs. VOL-O-FLO CALIBRATION The intercomparison test compares the input and output Vol-O-Flo elements to determine if the flowmeters need calibration. It is performed more often than the orifice calibration test as it is quicker and easier to perform. The orifice calibration check accurately determines whether the output Vol-O-Flo is within calibration tolerances. When a test stand fails the intercomparison test, an orifice calibration check is performed. Failure of the intercomparison test and orifice calibration check requires the removal and clean- ing of the input and output Vol-O-Flo elements. NOTE: Prior to performing these calibra- tion checks, you should ensure that there is no test stand leakage. After cleaning, drying, and reinstallation of the Vol-O-Flo elements, both the intercomparison test and the orifice calibration check must be repeated. Failure of the above tests after clean- ing will require the test stand be calibrated with a master calibrator, used by the metrology calibra- tion team. VOL-O-FLO ELEMENT CLEANING To clean the Vol-O-Flo element, proceed as follows: 1. Disconnect the tubes from Vol-O-Flo manometers. NOTE: Prior to removal of the element, mark the direction of the flow to ensure proper reinstallation. 2. Disconnect the element from the plumbing system by removing the hose and hose clamps at the ends of the element. 3. Mix a cleaning solution of 4 percent liquid detergent and water. (Mix 6 ounces of detergent with 1 gallon of water.) 4. Flush the element in reverse from the direction in which the air normally flows. 5. After the element has been well flushed, the detergent is rinsed out immediately with clean water. 6. Install the element in the test stand, and create a flow through the element for approximately 1 hour to ensure that it is completely dry. 7. After the element is dried, the test stand is leak-tested. 8. Perform an intercomparison test and orifice calibration check in accordance with the NAVAIR 13-1-6.4. LIQUID OXYGEN CONVERTER TEST STANDS Liquid oxygen converters are another group of items that you, as a PR, are required to test and repair. There are two test stands designed to test the oxygen converters. The operation, maintenance, and parts are, with a few minor 11-13