Piper COMANCHE PA-24-180 Service Manual page 244

PIPER COMANCHE SERVICE MANUAL
2.
Install insulator actuator and micro switch on quadrant plate and secure with screws,
lockwashers and nuts.
3.
Adjust switch per paragraph 6-63.
4.
Install cover on quadrant and secure with screws.
6-63. Adjustment Of Landing Gear Warning Switch.
a. Adjust the landing gear warning micro witch located on the throttle shaft forward of the
instrument panel by using the following procedure:
b. When properly adjusted the landing gear warning horn should operate when the power is reduced
below 10 to 12 inches of manifold pressure with the airplane in normal descent and the landing gear
retracted.
1. Start and run up the engine with the propeller set for high RPM. Retard the throttle until
approximarely 4 inches of manifold pressure on the PA-24-180, PA-24-250 and PA-24-260 and 5 inches of
manifold pressure on the PA-24-400 is indicated above the desired inflight pressure.
2. Mark the throttle shaft in some manner so that it can be returned to the proper manifold
pressure setting indicated during the run-up after the engine has been shut down.
3.
Place the airplane on jacks and retract the gear. Retard the throttle to the location which gave
the desired manifold pressure indication.
4.
Adjust switch on airplanes with Serial Nos. 24-1 to 24-4782 incl., 24-4784 to 24-4803 incl.
and PA-24-400 by the following procedure:
(a) With the battery master switch on, loosen the mounting screws or set screws on the micro
switch mounting bracket and move the bracket fore and aft until the warning horn starts to operate.
Tighten the mounting screws to secure the switch assembly. The switch may also be adjusted up or down to
allow proper clearance of the micro switch button on the throttle shaft.
5. Adjust switch on airplanes with Serial Nos. 24-4783, 24-4804 and up, by the following
procedure:
(a) Remove the left trim cover from the throttle quadrant by removing attaching screws.
(b) With the battery master switch on, loosen the micro switch mounting screws and move
switch toward actuator roller, on the throttle lever, until warning horn starts to operate. Tighten mounting
screws securing switch to quadrant plate and install cover.
6.
Operate the throttle to ascertain that the horn operates at the mark, and with warning horn
operating, lower the gear to insure that the horn ceases to operate when the gear is down and locked.
7.
Remove the airplane from the jacks and flight test to insure operation of the warning horn
when the gear is up and power is reduced below the desired manifold pressure. If the horn fails to operate
at the required setting, mark the throttle shaft
at
the desired manifold pressure and reset micro warning
switch.
LANDING GEAR AND BRAKE SYSTEM
ISSUED: 8/18/72
1K4