Prop-Synch Switch Removal And Installation; Pulse Generators Removal - Piper PA-44-180 SEMINOLE Maintenance Manual

With the exception of the coil short light, disregarded other
lights that may come on at this time .
5 . The illumination of the coil short light indicates that the solenoid coil in the right (slave) propeller
g o vernor is shorted. Position the aircraft master switch to OFF and replace the coil or governor.
It may be necessary to rotate the propeller two full turns to
i l l uminate or extinguish the light.
6. If the light for the right engine is OUT, rotate the propeller in the direction of normal rotation until it
becomes lit.
7. If the light is illuminated, rotate the propeller as explained in Step 6, until it just extinguishes.
8. Repeat Steps 6 and 7 for the left engine.
9. Place the synchronization prop-synch switch on the power control quadrant in the manual position.
1 0 . Check to see that the MANUAL light is illuminated on the test box, and the PHASE light extinguished.
When the switch is set to the auto-synch position, the PHASE light should illuminate.
11. If any test set lights did not operate properly, check the following:
A. Wiring harness for shorts.
B. Open circuit breaker.
C. Broken wires.
D. Wires connected to the wrong pins.
E. Compliance with schematic/wiring diagram.
F. Malfunctioning pulse generator as explained in Figure 61-7.
12. If the wiring harness checks good, but the right or left engine, or coil light does not function properly,
check the pulse generator as explained in Figure 61-7, Pulse Generator Backup Test. Replace the
g e nerator or governor as necessary.
PROP-SYNCH SWITCH.
REMOVAL AND INSTALLATION OF PROP-SYNCH SWITCH.
1. Remove the knobs from the control levers. Remove the upper control quadrant cover.
2. Remove the retaining nut from the toggle side of the switch; remove the switch from the cover.
3. Slide the shaded wire protective covering off the soldered connections.
4. Make a note of where each specific wire is soldered; remove the wires from their terminals.
5. Install the wires on the new switch as noted. Install the switch in the opposite manner of removal.
Install the switch in the cover with the barrel keying slot in the MANUAL direction of the switch.
PULSE GENERATOR(S).
REMOVAL OF PULSE GENERATOR(S). (Refer to Figure 61-6.)
1. The pulse generator is located behind the access panel on the outboard side of each nacelle just above
the leading edge of each wing, Refer to Figure 6-3 (cont.)
2 . Remove the electrical connection. Remove the four screws fastening the bracket (to which the pulse
g e nerator is attached) to the web; pull the unit through the access hole. If the tachometer cables are
too tight, loosen or remove the clamps holding them.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— NOTE —
— NOTE —
3D13
61-10-00
Page 61-11
Revised: June 20, 1995