TM 55-1520-240-23-3
4-14
PERFORM ENGINE VIBRATION TEST
(Continued)
4-14
49.
Set OPERATION selector (22) to C. Meter (3)
shall indicate between 14.0 and 1/16 inch
beyond full scale.
50.
Push CALIBRATE SIGNAL control (24). Meter
(3) shall indicate 10.5. Release control.
51.
Test must be performed again if meter (3) does
not indicate readings in steps 50 and 51.
52.
Have pilot land helicopter and shut down engines.
REMOVE TEST SET
53.
Disconnect meter (3) from power source.
54.
Disconnect battery (Task 1-39).
55.
Open engine work platform (Task 2-2).
56.
Open engine access cover (Task 4-49).
57.
Remove six screws (8 and 17).
58.
Remove two transducers (7 and 16).
59.
Remove three bolts (14), washers (15), and
adapter (12).
4-123