Textron Lycoming IO-540 Series Operator's Manual page 89

TEXTRON LYCOMING OPERATOR'S MANUAL
0-540 & 10-540 SERIES
SECTION 5
(11) Hold the magneto in its No. 1 firing position (tooth in window
center and pointer over R or L mark on rotor) and install magneto
to the engine and loosely clamp in position.
(12) Attach red lead from the timing light to left switch adapter lead,
green lead of timing light to right switch adapter lead and the black
lead of the light to magneto housing.
(13) Turn the entire magneto in direction of rotor rotation until the
red timing light comes on.
(14) Rotate the magneto in the opposite direction until the red light
just goes off indicating left main breaker has opened. Then evenly
tighten the magneto mounting clamps.
(15) Back the engine up approximately 10
°
and then carefully "bump"
the engine forward at tie same time observing the timing lights.
(16) At the No. 1 firing position of the engine, the red light should
go off indicating left main breaker opening. The right main breaker,
monitored by the green light, must open within + 2 engine degrees
of the No. 1 firing position.
(17) Repeat steps (13) thru (15) until the condition described
in
paragraph (16) is obtained.
(18) Complete tightening of the magneto securing clamps by torque-
ing to 150 inch pounds.
(19) Recheck timing once more and if satisfactory disconnect timing
light. Remove adapter leads.
(20) Reinstall plugs in timing inspection holes and torque to 12 - 15
in. lbs.
5-5