Piper PA-28-161, Maintenance Manual

Page: 936 / 1104

PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
PAGE 14
Nov 30/06
5C20
74-10-00
(4) Install Woodruff Key by pressing Woodruff Key into the key slot of the rotor shaft.
(5) In the left magnetos only (i.e. - impulse coupled), assemble impulse coupling:
(a) Assemble inner eye of the impulse spring into the grooves in the impulse hub.
(b) Set the impulse shell and untensioned impulse spring on the hub.
(c) Holding the shell in one hand and the pawls with the thumb and forefinger of the other hand,
pull the hub slowly, straight back, until its far enough to clear the projections on the shell.
CAUTION: DO NOT WIND THE IMPULSE SPRING MORE THAN 1/4 TURN.
(d) Hold the shell stationary and rotate the hub to wind the impulse spring until the
projections on the other section of the pawl plate pass the projections on the shell.
(Approximately 1/4 revolution or 90 degrees.)
(e) Ensure the shell is seated squarely on the hub and turns freely.
(6) In the left magnetos only (i.e. - impulse coupled), install impulse coupling:
(a) Install impulse coupling assembly onto the rotor shaft and install impulse washer.
(b) Install coupling nut and torque to 120 to 320 in.-lbs. to seat the coupling on the rotor shaft.
If cotter pin will not align with pin hole within the specified torque range, remove the nut
and lightly lap its bottom surface with emory cloth.
(c) Verify that the coupling is free by snapping it through 3 or 4 times.
(7) Install coil
(a) Place the frame on the T-125 assembly fixture. Insert the coil into the frame, being sure
that it is back against the stops. Insert coil wedges between the bridge and the frame.
(b) Drive the two wedges tight, using a hammer and flat punch. Attach the ground wire coil
(either black or white - depending on coil type) to the frame with a screw. Torque to 20 in.-lbs.
CAUTION: IF THE HIGH TENSION LEAD PROTRUDES ABOVE THE MAGNETO
FRAME, IT CAN MAKE DIRECT CONTACT WITH THE DISTRIBUTOR
GEAR AND CAUSE THE MAGNETO TO MALFUNCTION.
(c) Position the coil high tension lead flush to 1/32 (.031) inch below the parting surface of the
magneto frame.
(8) Install contact points - All magnetos
Attach contact point assembly on the bearing cap using appropriate screw.
(9) Install rotor cam
(a) Install cam using a light hammer and T-151 cam and rotor set.
(b) Drive the cam until it bottoms in the rotor cam slot.
(10) Time the magneto internally - Set primary points - All magnetos
(a) Place the magneto on the T-125 assembly fixture, flange down, with the T-509 timing base
adapter removed.
(b) In the right magnetos only (i.e. - non-impulse coupled), install the T-123 timing plug on the
rotor shaft before placing the magneto on the T-125 assembly fixture.
(c) Looking directly down on the magneto, align the magneto so that the coil is oriented in the
12 o'clock position.