Piper PA-28-161, Maintenance Manual

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PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
PAGE 2
Nov 30/06
3I22
37-10-00
3. Vacuum Pump
NOTE: In S/N’s 2842218 and up, for airplanes equipped with the optional EFIS: no vacuum system is
installed.
A single engine-driven dry-air pump is mounted on the accessory section at the rear of the engine. The
vacuum pump is a rotar y vane, positive displacement type. These units consist of an
aluminum housing, a carbon rotor and carbon vanes. They are driven by means of a coupling mated to
an engine-driven gear assembly.
Parker-Hannifin Airborne pumps were original equipment in S/N’s 2842001 thru 2842165 . Beginning with
S/N’s 2842165 & later, and for all service replacement requirements, Aero Accessories Tempest pumps
are installed.
A. Inspection - Aero Accessories Tempest Pumps Only (See Figure 1.)
The vacuum pump(s) feature a wear indicator inspection port on the back cover which allows direct
observation of pump vane wear. Beginning at 500 hours time-in-service, and each 100 hours
thereafter, remove the inspection port plug and observe vane wear as shown in Figure 1.
(1) As the vanes wear, they slide outboard in the vane slots in the rotor.
(2) When the portion of the vane that can be observed in the inspection hole covers approximately
1/8 of the inspection hole, replace the pump.
Vacuum Pump Vane Wear Inspection
Figure 1