barfield 1811GA Series User Instruction Manual

Contents

barfield 1811GA Series User Instruction Manual Manual pdf 43 page image

56-101-00184 / 00185 Rev. I CH. 4September 24, 2014 Page 31 of 56CHAPTER 4. VALVE LEAK TEST1. METERING VALVE ADJUSTMENT PROCEDURENote: The following procedure is also released as IM150 (dated 7/6/88.)A. Valve Leak TestCaution: Before performing the Valve Leak test, inspect for system or instrumentleakage. (Refer to the appropriate Aircraft Maintenance Manual forinformation and proper procedure.)Note: Read sections “A” and “B” before performing test since steps listed in sectionsmust be done in combination when performing valve adjustments.B. Pressure Valve Test(1) Close all valves except "VACUUM VENT".(2) Plug "PRESSURE" and "VACUUM PORTS". (Single action pumps only.)(3) Pressurize "PRESSURE TANK" to 15 psi.(4) Monitor AIRSPEED INDICATOR for one (1) minute.(5) If there is an increase in airspeed seen, continue to monitor for an additional five(5) minutes.Note: If during the monitoring period the increase exceeds five (5) knots, a leakexists at the "PRESSURE" valve.(6) Correct leak before continuing (Refer to this section 2. RESETTING NEEDLEVALVE POSITIVE STOP).C. Pressure Vent and Crossbleed Valve Test(1) Close all valves except "VACUUM VENT".(2) For single action pumps, plug the "PRESSURE" and "VACUUM " ports.Caution: Do not over pressurize airspeed.(3) Apply enough pressure to the "PRESSURE TANK" to provide FULL SCALEAIRSPEED INDICATOR TRAVEL.(4) Gently open the "PRESSURE" valve. Increase the airspeed to FULL SCALE.(5) Close "PRESSURE" valve.(6) Monitor the AIRSPEED INDICATOR for one (1) minute.Note: If there is a decrease of more than two (2) knots, a leak exists at the"PRESSURE VENT" or "CROSSBLEED" valve.