Installation And Timing Procedure (Timing Magneto To Engine) - Piper PA-24 Comanche Service Manual

PIPER COMANCHE SERVICE MANUAL
•
TIMING MARK
FIGURE 7·15. ENGINE TIMING MARKS
7-44. Installation And TimiDJ Procedure. (TiJhinl Maplcto
to
Enpe.) The mlJnetos can be installed and
nmed to the enatne by the foUowinl procedure;
NOTE
Ascertain that the breaken are .:orrect for proper internal timing of
magnetos.
a. Lift the et\!lne cowling side panels.
b. Remove the tOP spark pll.ll from
~o.
one cylinder. Place the thumb of one hand over the spark
plug hole and rotate the crankshaft in direction of nonnal rotation until the comprc5,1ion srroke
IS
reached.
The compression stroke is indicated by a positive pressure inside the cylinder tending to lift the thumb cif
the spark plug hole. In this posinen both valves of No, one l:)'linder ate dosed. Turn the crankshait
opposite to its normal direction of rotation until it is approximately 35 degrees BTe on the compressicn
stroke of No. one cylinder. Rotate the crank.maft in its normal direction of rOtation until the 25 degrees
mark on the back of the starter gear and the crankcase panUlg sutiaee are aligned. or the marks on the front
of the starter rinl gear and the drilled hole in the starter housing align. (Refer to Figure i-I 5.)
NOTE
The impulse coupling magneto l-21) or the ·ZOO shower of sparks
magneto can be used only on the left side of the engtne
I
a.s
viewed from
the rear).
POWER PLANT
REVISED: 4/10/81
2 812
•
•