Pulse Generators Post Installation Check; Pulse Generators Flight Check - Piper PA-44-180 SEMINOLE Maintenance Manual

8. If the test set lights are NOT ON, rotate the required generator (in the opposite direction of the other)
on its bracket to its exact point the light comes on. If BOTH LIGHTS ARE OFF on the test set, rotate
the generators to their timing mark alignments. Remember to turn opposing generators in opposite
directions in reference to viewing each through their access holes.
Any time a question develops as to the condition of a generator,
test the generator as explained in Figure 61-7.
9. Tighten the reliance nuts as much as possible to prevent the generators from turning; cross mark the
generators to their brackets.
10. Carefully remove bracket and generator.
11. Check mark on bracket and generator to make sure the generator has not moved, and tighten the
reliance nuts on the generators to secure them on their brackets. Bend the tab washer to lock the
reliance nut in place.
12. Permanently install assemblies and perform the ground test.
13. Check to make sure the propeller synch switch is in the manual position.
POST INSTALLATION CHECK.
1. Refer to the wiring diagram in Chapter 91 and check that all wiring has been correctly installed.
2. Check continuity between the pins of the Amphenol plug, 57-30140, to see that any two pins are not
shorted together. This usually occurs between pins that are side by side. Plug the harness into the compute r.
3. Connect a DC ammeter with at least a two amp scale in series with one of the governor wires. Refer to
the wiring diagram to be sure the ammeter is connected with the proper polarity. The solenoid coil
gets its power from pin 13 of the Amphenol 57-30140 plug.
4. Put the prop-synch switch in the MANUAL position and turn the ship's master switch on. The current
reading should go immediately to about one amp and rest there. Turn the master switch off and connect
the governor wire into the harness.
5. Connect a voltmeter from pin C of the MS3106A 10SL-3S plug at the pulse generator to ground. With
the master switch ON, rotate the engine either direction. The voltage reading should alternate from
zero to about twelve volts once for every two revolutions of the propeller.
FLIGHT CHECK.
This operation must be conducted by two people; one to concentrate
on flying and the other to conduct the check procedure.
1. Before starting engines make sure the prop-synch switch is in the manual position.
2. Attain a cruise altitude and set the power controls at 75% power.
3. Beat synchronize the propellers manually.
4. Increase or decrease the propeller speed by 30 RPM with the propeller control.
5. Move the prop-synch switch to its auto-synch position. If synchronization is not accomplished, repeat
the above procedure but using 25 RPM instead of 30 RPM.
6. If synchronization still is not accomplished repeat the Ground and Installation Checks.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— NOTE —
— NOTE —
See Figure 61-7 for a backup check on the pulse generators.
— NOTE —
3D16
PPS-55041C
61-10-00
Page 61-14
Revised: May 15, 1989