Piper Arrow IV Turbo Maintenance Manual page 618

12. Inspect coil leads for damaged insulations and terminals for tightness and soldered connection.
13. Inspect impulse coupling parts for excessive wear. Particularly check clearance between cam and
flyweights of the cam assembly. Measure the clearance between the cam flyweights using the shank of a new
No. 18 drill (0.169 inch diameter). If the drill will fit between cam and flyweight as shown in Figure 74-4, the
cam assembly must be replaced. Check clearance between both flyweights and the cam of each cam assembly.
14. Check the clearance between each flyweight and each stop pin as follows:
A. Bend the end of a stiff piece of wire into a right angle 0.125 inch long (maximum).
B. Hold magneto as shown in Figure 74-5. Pull heel of flyweight outward with the hooked wire and
make certain that feeler gauge of 0.010 inch minimum thickness will pass between stop pin and
the highest point of the flyweight.
A true and accurate check of the clearance between flyweight
and stop pin can only be obtained by pulling the flyweight
outward as described above. Do not attempt the check by pushing
in on flyweight at point "A."
15. Check internal timing and reinstall and time magneto to engine.
A pressurized magneto retrofit kit is available. Installation of this
kit (764 921v) will provide pressurized air to the magneto,
improving ignition system operation at higher altitudes and
reducing the frequency of ignition system maintenance.
Effectivity
PA-28RT-201T
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
Figure 74-3. Contact Points
—NOTE—
—NOTE—
3D14
74-11-00
Page 74-05
Revised: July 13, 1983