Cessna 152 - Page 119

CESSNA
MODEL
152
SECTION7
AIRPLANE
&
SYSTEMS
DESCRIPTIONS
aviation
grade
straight
mineral
oil
conforming
to
Specification
No. MIL-
L-6082.
ENGINE OIL
SYSTEM
Oil
for
engine
lubrication
is
supplied
from
a
sump
on
the
bottom
of
the
engine.
The
capacity
of
the
engine
sump
is
six
quarts
(one
additional
quart
is
required
if
a'full
flow
oil
filter
is
installed).
Oil
is
drawn
from
the
sump
through
an
oil
suction
strainer
screen
into
the
engine-driven
oil
pump.
From
the
pump,
oil
is
routed
directly
to
the
oil
cooler
and
returns
to
the
engine
where
it
passes
through
the
pressure
screen,
if
the
engine
does
not
incorporate
a
full
flow
oil
filter.
If
the
engine
is
equipped
with
a
full
flow
oil
filter,
oil
passes
from
the
pump
to
a
thermostatically
controlled
bypass
valve.
If
the
oil
is
cold,
the
bypass
valve
allows
the
oil
to
bypass
the
oil
cooler
and
flow
directly
to
the
filter.
If
the
oil
is
hot,
the
bypass
valve
routes
the
oil
from
the
accessory
case
forward
through
a
flexible
hose
to
the
engine
oil
cooler
mounted
on
the
leftJorward
side
of
the
engine.
Returning
to
the
accessory
case,
the
oil
passes
through
the
filter.
The
filtered
oil
then
enters
a
pressure
relief
valve
which
regulates
engine
oil
pressure
by
allowing
excessive
oil
to
return
to
the
sump,
while
the
balance
of
the
pressure
oil
is
circulated
to
various
engine
parts
for
lubrication.
Residual
oil
returns
to
the
sump
by
gravity
flow.
An
oil
filler
cap/
oil
dipstick
is
located
at
the
rear
of
the
engine
on
the
right
side.
The
filler
cap/
dipstick
is
accessible
through
an
access
door
in
the
engine
cowling.
The
engine
should
not
be
operated
on
less
than
four
quarts
of
oil.
To
minimize
loss
of
oil
through
the
breather,
fill
to
five
quarts
for
normal
flights
of
less
than
three
hours.
For
extended
flight,
fill
to
six
quarts
(dipstick
indication
only).
For
engine
oil
grade
and
specifications,
refer
to
Section
8
of
this
handbook.
An
oil
quick-drain
valve
is
available
to
replace
the
drain
plug
in
the
oil
sump
drain
port,
and
provides
quicker,
cleaner
draining
of
the
engine
oil.
To
drain
the
oil
with
this
valve
installed,
slip
a
hose
over
the
end
of
the
valve
and
push
upward
on
the
end
of
the
valve
until
it
snaps
into
the
open
position.
Spring
clips
will
hold
the
valve
open.
After
draining,
use
a
suitable
tool
to
snap
the
valve
into
the
extended
(closed)
position
and
remove
the
drain
hose.
IGNITION-STARTER SYSTEM
Engine
ignition
is
provided
by
two
engine-driven
magnetos,
and
two
spark
plugs
in
each
cylinder.
The
right
magneto
fires
the
lower
right
and
the
upper
left
spark
plugs,
and
the
left
magneto
fires
the
lower
left
and
upper
right
spark
plugs.
Normal
operation
is
conducted
with
both
magne-
tos
due
to
the
more
complete
burning
of
the
fuel-air
mixture
with
dual
ignition.
1
July
1978
7-17