Cessna 182 1978 - Installation and Timing to Engine; Internal Timing; Magnetos

MODEL
182 &
T182 SERIES
SERVICE
MANUAL
11-73. MAGNETOS.
NOTE
11-74.
DESCRIPTION.
The magnetos
contain a con-
As
the magneto is
removed from
its mount-
ventional
two-pole rotating
magnet (rotor),
mounted
ing,
be sure that the
drive coupling
rubber
in ball
bearings. Driven by the
engine through an
bushing and
retainer do not become
dislodged
impulse coupling
at one end, the
rotor shaft operates
from the gear
hub and fall into the engine.
the breaker points
at the other end of
the shaft. The
nylon rotor gear drives a nylon distributor gear which 11-76. INTERNAL TIMING.
transfers high
tension current
from the wedge-mount-
a. Whenever
the gear on the
rotor shaft or
the cam
ed coil to the proper
outlet in
the distributor block.
(which
also serves
as the key for
the gear) has
been
A coaxial
capacitor is mounted
in the distributor block
removed, be sure
that the gear and cam
are installed
housing to
serve as the condenser
as well
as a radio
so the timing
mark on the gear
aligns with
the "O"
noise suppressor.
Both nylon gears
are provided
etched on
the rotor shaft
with
timing marks
for clockwise
or counterclockwise
b.
When replacing
breaker assembly
or adjusting
rotation. The distributor
gear and distributor
block contact
breaker points, place a
timing pin (or 0. 093
have
timing marks, visible through the air vent holes,
inch 6-penny nail) through the timing hole
in the bot-
for timing to the
engine. A timing hole
is provided tom
of the magneto next
to the flange and into the
in the bottom of the magneto
adjacent to the
magneto mating
hole in the rotor shaft.
Adjusting contact
flange.
A timing pin or 6-penny
nail can be inserted
breaker points
so they are just starting
to open in
through this timing hole into the
mating hole in the this position will
give the correct point setting.
rotor shaft to lock
the magneto
approximately
in the Temporarily
assemble
the magneto
halves and
cap-
proper firing position.
The breaker assembly
is acitor
slip terminal and use
a timing light to check
accessible
only after
removing the screws
fastening
that the
timing marks,
visible through
the ventilation
the magneto
halves together
and disconnecting
the
plug holes
are approximately
aligned.
capacitor slip
terminal. Do not
separate magneto
halves
while it is installed
on the engine
or internal
NOTE
timing
may be
disturbed.
The sideof the magneto with the manu-
11-75.
REMOVAL.
facturer's
insignia
has a
red timing
mark
a.
Remove
engine cowling
in
accordance
with
para-
and
the side
opposite
to the
insignia
has
graph
11-3.
a black
timing mark
viewed
through the
b. Tag for
identification
and
remove high
tension
vent plug holes.
The
distributor
gear
wires
from the
magneto
being
removed.
also
has a
red timing
mark
and a black
on the engine. Do not place red and black
The magneto
is in a
SWITCH ON
condition
lines together
on the same
side.
when the switch wire is disconnected. Re-
move the high tension wires from magneto
c. Whenever the large distributor
gear and rotor
or disconnect
spark plug leads from
the
gear have been disengaged,
they must be engaged
spark plugs to prevent accidental firing. with their timing marks aligned for correct rotation.
Align the timing mark on the rotor gear with the
c. Disconnect
switch wire from condenser terminal "RH"
on the distributor gear. Care must be taken
to
at magneto. Tag wire for identification so it may be keep these two gears meshed in this position until
installed correctly. the magneto halves are assembled.
d. Rotate propeller
in direction of normal
rotation
until No. 1 cylinder is coming
up on its compression 11-77. INSTALLATION
AND TIMING TO ENGINE.
stroke.
The magneto
MUST be
installed with
its timing
marks correctly aligned, with the number one cylin-
NOTE
der
on its
compression
stroke
and with
number
one
piston at its advanced firing position. Refer to para-
To facilitate
the
installation
of a
replacement
graph
11-12
for the advanced
firing position
of num-
magneto,
it is
good
practice
to position
the
ber
one piston.
crankshaft at the advanced firing angle for
No. 1 cylinder
during step "d."
Any standard
timing device or method
can be used, or if the
magneto being
removed is correctly
timed to
the engine,
the crankshaft can be rotated to a
The magneto is grounded through
the ignition
position at which the breaker points
will be switch, therefore,
any time the switch
just
opening to
fire No. 1 cylinder.
(primary) wire
is disconnected
from the
magneto, the magneto is in a switch ON or
e. Remove
magneto
retainer
clamps,
nuts
and
HOT condition.
Before turning
the
propeller
washers and
pull magneto
from crankcase
mounting
by hand,
remove the high
tension wires
from
pad.
the magneto or disconnect
all spark plug
leads
to prevent accidental
firing of
the engine.
Revision
1
1-25