Piper COMANCHE PA-24-180 Service Manual page 470

PIPER COMANCHE SERVICE MANUAL
FIGURE 7C-14. ENGINE TIMING MARKS FIGURE 7C-15. MAGNETO TIMING MARKS
b.
Continue turning the crankshaft until the 250 advance timing mark is in alignment with the small
hole located on the top face of the starter housing at the two o'clock position. (Refer to Figure 7C-14 )
c
Remove the inspection plug on the left magneto and turn the drive coupling in direction of normal
rotation until the first painted chamfered tooth is aligned in the center of the inspection hole. (Refer t
Figure 7C-15 ) Without allowing the gear to turn from this position, assemble gasket and magneto to
engine Secure in place with washers and nuts. tighten only finger tight
d.
Fasten ground wire of electric timing light to an! unpainted portion of the engine. and one of the
positive wires of the timing light to a suitable terminal connected to the ground terminal of the magneto
Then turn the engine crankshaft se'eral degrees from the advance timing mark in direction opposite to that
of normal rotation.
e
Turn on the switch of the timing light. which should be lit: Turn the crankshaft slowly in direction
ol normal rotation until the mark on the starter gear aligns with the hole in the starter housing. at which
point the light should go out. If not. turn the magneto in its mounting flange and repeat the procedure until
the light goes out Repeat the same procedures with the right magneto
NOTE
Battery powered timing lights operate in the reverse manner from
that described abo'e: the light goes on when the marks align.
f
After both magnetos have been timed. leave the timing light wires connected and recheck
magnetos as previously described to make sure that both magnetos are set to fire together If timing is
correct. both timing lights will go out simultaneously when the timing marks are in alignment Tighten nuts
to specified torque
POWER PLAO
REVISED: 4/10/81
2H16