Piper Aircraft Corporation Malibu Mirage PA-46-350P, Airplane Maintenance Manual

Page: 1097 / 1956

PAGE 1
Feb 28/07 6D3
37-10-00
PIPER AIRCRAFT, INC.
PA-46-350P, MALIBU MIRAGE
MAINTENANCE MANUAL
DISTRIBUTION
The following information is intended to acquaint field service personnel with a means to diagnose
vacuum system service symptoms on those components which are serviced by removal and
replacement. These items include hoses, clamps, gyro filters. vacuum regulating valves, and vacuum
gauges.
1. Hoses and Clamps
A. These items should be examined periodically and inspected carefully whenever maintenance
activities cause hose disconnections to be made at the pumps, manifold, regulators, tube
assemblies, gyros and/or vacuum gauge.
B. Ends of hoses should be examined for rubber separation and slivers of rubber on inside
diameter of hoses. These slivers can and do become detached. If this happens, the vacuum
pump(s) will suck in the loose particles and eventually ingest them. This can cause pump failure.
C. Replace old, hard, cracked or brittle hose. Sections of the inner layers may separate, causing pump
failure.
D. Ensure hoses are clear and clean by blowing them out with shop air. Remove from aircraft as
required.
CAUTION: DO NOT WIGGLE HOSE FROM SIDE TO SIDE DURING INSTALLATION. WIGGLING
COULD CAUSE PARTICLES TO BE CUT FROM INNER WALL OF HOSE WHICH
WOULD DAMAGE THE PUMP.
E. Where hose clearance is tight, making it difficult to reinstall it onto a fitting or barb, spray the fitting
or barb with silicone. Let dry, then install hose by pushing it straight on.
CAUTION: WHEN REPLACING ANY OF THE THREADED FITTINGS, DO NOT USE PIPE
DOPE, THREADLUBE, OR TAPE. PIPE DOPE / TAPE PARTICLES INGESTED BY
THE VACUUM PUMP COULD CAUSE THE PUMP TO FAIL. USE ONLY SILICONE
SPRAY, LETTING IT DRY BEFORE ASSEMBLY.
F. Hose clamps and fittings should be replaced when broken, damaged or corroded.
2. Gyro Filter
A. Gyro filters must be serviced on a scheduled basis, not to exceed 100 hours, or sooner as condition
indicates.
B. The system installation employs a large central filter and differential vacuum gauge that
continuously monitors the filter condition while indicating vacuum readings.
NOTE: A decline in panel gauge reading indicates the filter is becoming clogged. Filters should be
replaced when gauge reading declines; DO NOT adjust regulator(s).