Section
L2
Introduction
The
sealed
cooling
system
comprises
a
pressurized
expansion bottle.
a
radiator. and
a
pump.
Also,
various
passages and pipes
convey
the coolant around the
system
(see
fig.
12-1
1.
A
mixture
containing
equai
amounts
of
approved
coolantlanti-freeze and water should
be
used
in
the
system at at1 times.
The coolant
mixture
in
the system should
always
be
maintained at
the
correct level and this
must
be
checked
at
the intervals
specified
in
the
Service
Schedule
Manual,
TSD
4702.
The
coolant
level
can
be
checked
at
the
translucent
expansion bottle.
The
correct
level
should
be
between
the
MAX
and MIN marks on
the
bottle.
If
afull
checkis
to
be
carried
out
refer to page
L3-3.
Thecooling system
is
pressurized and
the
correct
pressure
is
maintained
by
the
expansion bottle
pressure
cap.
Removal
of
the
pressure
cap
while
the
engine
and
radiator
are
still
hot
requires
extreme
care.
The
coolant
pump
is
situated
at
the
front
of
the
engine
and
is
driven
from
the crankshaft
by
twin
matched
'Vee'
belts.
Coolantfrom the bottom of the radiator
is
pumped
via
transfer
pipes
and
crankcase
passages directly
onto the outside
of
the
'wet'
type
engine
cylinder
liners
and then into
the
cylinder
heads.
From the
cylinder
heads
the coolant travels
along
transfer pipes
and then flows
past
the thermostat
to
the top
of
the
radiator.
When
the
engine
is
cold
the
thermostat
is
closed.
Therefore, the coolant
by-passes the
radiator matrix
and
is
recirculated
through
the
engine
to reduce
the
warm-up
period.
Once normal
operating
temperature
is attained, the thermostat opens and the coolant
is
directed to
the
radiator.
The temperature of
the
coolant is registered
on
the
gauge
situated
on
the facia. Whenever the ignition
ison,
a
transmitter
situated
in
the
thermostat housing
signals the coolant temperature to the
gauge.
Fig.
K-1
Diagrammatic
view
of
the
cooling
system
Dotted
line
-
1989
model
year
cars
5/88
'
TSD
4700
