Piper Cherokee SIX 300 Service Manual page 431

PIPER CHEROKEE SIX SERVICE MANUAL
1. Loosen rotor holding tool and move the rotor back a few degrees; then move it
forward. Both lights should go out to indicate opening of the main breakers when the timing
pointer is indicating within the width of the "R" mark and the red painted teeth are
centered in timing windows.
m. If breaker timing is not correct, loosen cam securing screw (refer to Figure 7A-34)
and unseat main breaker cam from taper. Using 11-3031 Retaining Ring Pliers inserted in
holes in cam, rotate main breaker cam in direction of rotation until left main breaker points
just open and press cam onto taper. Tighten screw to seat main breaker cam.
n. Loosen rotor holding tool to turn rotating magnet back a few degrees; then turn
rotating magnet in normal direction of rotation. Timing light should go out when timing
pointer is aligned with "R" ("E" gap) mark. Lock rotating magnet in position where points
just open.
o. Loosen right main breaker securing screws and position breaker so cam follower is
pressed against cam with points closed. Tighten contact assembly securing screws to prevent
contact assembly from bouncing back when moved. Using a small mallet and drift, tap right
breaker in until points just open.
p. Turn rotating magnet back a few degrees; then turn rotating magnet in normal
direction of rotation. Both timing lights should go out within one degree or half the width
of "R" mark on rotor. If breakers are not properly synchronized, reset right breaker.
q. Check right main breaker contact for 0.016 ± .004 inch point opening and torque
right breaker contact securing screws to 20-25 inch-pounds. If point opening is out of limits,
repeat timing procedure setting left main breaker opening at .016 + .002 inch. If right
contacts open beyond .020 inch, set left contacts closer to .018 inch. If right contacts open
less than .012 inch, set left contacts closer to .014 inch.
r. Using timing light, recheck timing to insure main breakers open within one-half the
width of "R" mark and that retard breaker opens at correct degree setting. Using a wire
feeler gauge, check left main breaker for .016 ± .002 inch point opening and right main
breaker and retard breaker for .016 ± .004 inch point opening.
NOTE
If correct breaker timing cannot be achieved, remove
magneto and have it overhauled.
s. Check capacitors for looseness in the magneto cover of the harness assembly and for
any physical damage. The capacitors should be checked for capacitance, series resistance and
leakage. Capacitance should be 0.34 to 0.41 microfarads. The use of a Bendix condenser
tester, part number 11-1767-1, -2 or -3 or equivalent will simplify this test. Replace
defective capacitors and torque securing nut to 60-70 inch-pounds.
NOTE
Spring in capacitor outlet may cause an indication of a short
to ground if adapter lead is not used. (Refer to Paragraph
7A-39, Step c, Note.)
POWER PLANT
Revised: 7/28/75
2H19