Cessna 172N - Engine Systems and Operation

SECTION
7
AIRPLANE
&
SYSTEMS
DESCRIPTIONS
CESSNA
MODEL
172N
surfaces
in a
neutral
position
and
prevent
damage
to these
systems
by
wind-
buffeting
while
the
airpl4ne
ii
parked.
The
lock
consists
of
a shaped
steel rod
with
a
red
metal
flag
attached
to
it.
The
ftag
is labeled
CON-
TR9l
LOCK'
REMOVE
BEFORE
STARTING
ENGINE:
To
instalt
the
con-
trol
lock,
align
the
hole
in
the
top
of the
pilot's
control
wheel
shaft with
the
hole
in
the
top
of
the
shaft coUar
on
t-he
instnrment panel
and
insert
the
rod
into
the
aligned
holes.
Proper
installation
of the
lock
will
place
the
red
flag
over
the
ignition
switch.
In areas
where
high
or
gusty
winds
occur'
a control
surface
lock
should
be
installed
over
th-e
vert--ical
stabi-
lizer
and
rudder'
The
control
lock and
any
other
type
of
locking
deviee
should
be
removed
prior
to
starting
the
engine.
EN
GIN
E
The
airplane
is
pow_ered
by
a horizontally-opposed,
four-cylinder,
overhead-valve,
air-cooled,
carbureted
engine
wittr a
wet
sump
oil
sys_
1"*.
The
engine
is
a
Lycoming
Model
O-320-HZAD
and is
raied
at
iOO
horsepower
at 27OO
RPM.
Major
accessories
include
a starter
and
belt-
driven
alternator
mounted
on
the front
of
the
engine,
and
dual
magne-
tos
and
a vacuum
pump
which
are
mounted
on
an accessory
drivJpad
on
the
rear
of
the
engine.
Provisions
are
also
made
for a full
flow
oil
filter.
ENGINE
CONIROTS
Engine power
is controlled
by a throttle
located
on the
lower
center
portion
of
the
instnrment
panel.
The
throttle
operates
in a conventional
manner;
in
the
fuIl
forward
position,
the throttle
is
open, and
in the
full
aft
position,
it
is
closed. A
friction
lock,
which
is a
round
knurled
disk,
is
located
at the
base
of
the
throttle
and
is operated
by rotating
the
lock
cloe"kwise
to increase
friction
or
counterclockwise
to-decreasJit.
The
mixture
control,
mounted
above
the
right
corner
of the
control
pedestal,
is
a
red
knob
with
raised
points
around
the
circumference
and
is
equipped
with
a lock
button
in
th-e
end
of
the knob.
The
rich
position
is
full
forward,
and
fuII
aft
is
the idle
cut-off
position.
For
small
ad-
justments,
the
control
may
be moved
forwarilby
rotating
the
knob
clockwise,
and
a.tt
!v
rotaling
the
knob
counterclockwise.
For rapid
or
l3,rge
adjustmenj,
tle
knob
m1y
be moved
forward
or
aft
by depressing
the
lock
button
in
the
end
of the
control,
and then positionlng
the
con-
trol
as
desired.
ENGINE
INSTRUfrTENTS
Engine
operation
is
monitored
by
the
following
instruments:
oil
7
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