
—NOTE—
Although not required, use of the slick T-100 assembly and timing kit is
strongly recommended. (Refer to Figure 8-7.) The tools contained in
this kit will greatly facilitate magneto disassembly / assembly and help
prevent damage to parts.
a. Remove cotter pin, nut, washer and gear. Grasp shell of impulse coupling assembly and gently pull the
assembly outward to clear the unlatching ears.
b. Allow the shell to turn, cautiously releasing spring tension, and withdraw the shell and coil spring. Using
slick puller T-106 engaged in the grooves on the impulse hub, pull the assembly off shaft taper and discard.
Remove key.
c. Remove four screws, and four washers. Separate the distributor housing sufficiently to disconnect the
condenser lead at the contact breaker assembly.
d. Remove two screws and two washers. Withdraw and discard bearing bar, distributor gear and distributor
block from distributor housing.
e. Using two flat blade screwdrivers or equivalent, placed under the rotor gear, gently pry the gear off the
rotor shaft and discard.
f. Remove and discard the breaker assembly by removing screw and washer. Remove cam by prying straight
up with a screwdriver blade and discard.
g. Remove two screws, two washers and two bearing plate clamps. Press against the drive end of the rotor
shaft and withdraw the rotor, bearing plate, loading spring and washer from the end frame. Place the rotating
magnet in a suitable keeper and press the ball bearings off the journals. Discard the ball bearings and washer.
h. Using coil wedge extractor T- 122, remove coil wedges and lift out and discard coil.
( Refer to Figure 8-9.) Remove air vents. Remove and discard oil seal.
—NOTE—
The following parts MUST BE REPLACED at overhaul on 4200 series
magnetos. Nine thick washers, one condenser, one distributor block,
one bearing bar, two ball bearings, one distributor gear, one coil, one
retaining washer, one loading spring, one impulse coupling, oil seal,
one contact point kit and one rotor gear. Refer to Slick Part List for part
No's.
8-27. CLEANlNG AND INSPECTION OF MAGNETOS. (4200 series)
a. Inspect internal and external threads of all threaded hardware. Damaged or worn parts must be replaced.
b. Inspect the bearing plate for excessive wear and damage. (Maximum bearing bore l.D. to be 1.5752 inch.)
c. Check the rotor for damaged or worn keyway. Check the rotor bearing surfaces for wear. (Minimum O.D.
to be 0.6690 inch.)
d. Inspect the magneto frame and distributor housing for cracks or other damage. Check the bearing bore in
the drive end frame for wear. (Maximum I.D. to be 1.5741 inch.)
e. Clean all parts thoroughly with a grease solvent before reassembly.
—NOTE—
No internal repairs are permissible. Replace all items showing wear or
damage, or that are not within the tolerances specified.
PIPER AIRCRAFT
PA-28-161 CADET
AIRPLANE MAINTENANCE MANUAL
Issued: FEBRUARY. 28, 1989
POWER PLANT
1J20