Installation Of Fuel Selector Valve - Piper Comanche PA-24 Service Manual

8-16a. Fuel Valve Internal Leak Inspection. (PA-24-400)
Each 50 hours time-in-service inspect as follows:
a. Position aircraft on relatively level ground with a minimum of one (1) gallon in each tank. Drain
fuel selector sump using normal preflight procedures.
NOTE: Observe all safety precautions required when handling gasoline.
b. With fuel selector in the "off" position, drain fuel selector by operating drain lever through the
access panel located between the front seats. Valve should be held "open" for one minute. Collect
content and discard.
NOTE: Because of residual fuel in the fuel selector sump bowl, several attempts may be required
to drain all fuel from the sump bowl. A leaking fuel valve is indicated by continued
draining when the fuel selector is in the "off" position. The volume and rate of this
drainage depends on the size of the leak.
c. Close drain valve and wait three (3) minutes. Drain fuel selector for one (1) minute, collecting
contents in a graduated container. Close drain valve. Contents collected must be less than one half
(1/2) fluid ounce.
d. If fuel collected exceeds one half (1/2) fluid ounce, repeat step C above.
e. If repeated collected fuel exceeds one half (1/2) fluid ounce, an excessive internal leaking fuel
selector is indicated. Clean the fuel selector valve in accordance with paragraph 8-18. Repeat steps
a through e above. If excessive internal leaking is still indicated, replace fuel valve with a new unit.

Installation of Fuel Selector Valve.

8-17.
Before installing the selector valve ascertain that fittings are properly positioned and installed. Do not over
tighten tapered fittings as this may damage the valve housing. For valves with straight thread type fittings,
with O-ring seals, tighten the locknut so that the O-ring seals on the non-threaded portion of the fitting.
a. Attach the selector valve to its mounting bracket and the bracket and valve to the aircraft.
b. Attach the fuel lines to the valve fitting. Add enough fuel to each cell to determine that there is no
fuel leaks.
c. Reinstall the floor panel and carpet.
d. If fuel selector switches are installed, connect wiring and carefully slide the main switch (12, Figure
8-12 or 8-13) on the valve shaft (1). Should the main switch fit loose on the vale shaft, shim the flat
of switch hole with 1/4 x 7/16 pressure sensitive adhesive tape (11). Spec. PPP-T-60B, Type III,
Class I.
e. Reinstall the selector handle and rotate it through its various positions, at the same time flushing the
fuel lines.
04/01/09
PIPER COMANCHE SERVICE MANUAL
2J5
VIII - FUEL SYSTEM