Engine Cooling And Lubrication; Radiator; Radiator Cap - Pontiac Grand Prix Service Manual

ENGINE COOLING
AND LUBRICATION
CONTENTS
O F
THIS SECTION
PACE SLJa.TECT
PAGE
Cooling System Ljescrrption
. . . . . . . . . .
6 A - 1
Ridintor
. . . . . . . . . . . . . . . . . . .
. 6 A - 4
. . . . . . . . . . . . . . . . . .
Radiator
a r K i
Cap
. . . . . . . . . . . . . . .
6 A - 1 WAter'
P i i c i ~ )
. . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . .
Water Pump. 6 A - 1 O i l Filter . 6 A - 5
. . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
Fan.
6 A - 2
Drive Belt Chart .6A-7
. . . . . . . . . . . . . . .
Service
O p e r a t ~ o n s
6 A 2
' I ' r > ~ . q \ \ r
Sprr-lf
i c a t ~ o r ~ s
. . . . . . . . . . . . .
4
6 A - 8
. . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . .
Ther~nostat 6 A -3 Service Specificatiuns. ~ A - B
GENERAL DESCRIPTION
ENGINE COOLING SYSTEM
The coaling system consisu
of the radiator, cap.
radiator hoses.
water
pump.
ctinling Pan. pellet-~ype
thermostat and suitahlc passiigcs for water
circulars-
tion through the engine.
RADIATOR-ALL MODELS
A
cross-flow radiator
i b
uled
on all
196')
Puntiacs
instead of the conventional down-fluw type. The
cross-flow
radialur diffe~s in
lhc
f a c ~ rhat
water flows
horizontally and the unks are on the left and right
side of the corc
insread r,C above
and hclow thc core.
'I'he i~oss-flow radiator offers imprnved cooling capa-
bilities while making possihle a
lower front end
aill~r~uzttc
duc
10
its rcduced
height. The
low,
wide
shape of
the cross-flow
radidtor nldtches the grille
opening more erticien
t
lv, providing greater radiator
exposure
and
more
efftc~ive
cooling surface.
Rddiators
used
with
automatic transtnission have oil
coolers hu111
into
the right
tank wit11 inlet
and
outIet
filtings Tor circulation of transmission fluid. The
Pontiac
radiator
used with
au~clrna~ic
trancrrlission i s
equipped with heavy duty
oil
cooler
when used
on
police can,
trailer options,
etc.,
and as optional
equiprnrnl where extreme cooling
conditions
muql
he
nict.
The
radialor used with the svn~.hrornesh
transmission
is a cross-flow without oil cooler.
C ~ r s
equipped with
air wndjtioning and
prrfhrm:ance options use
a
radiator which
has more uoohng capaciv for grealrr
cooking
demands.
A drain rock
1s
located
at
inside Icrwer lei1 corner of
radiator.
RADIATOR CAP
A pressure-vent cap is used on the radiator
to
allow a
build-up of
15
psi
of prefsure i n the cnuling
system.
This pressure raises the boding
poinr
i l T
cnolanr
to
approxitllately 258°F.
at
sea level.
C A UTION: As long
as
r
h u e
is pressurtm
i n
(he
~.ooling
system, the temperature
can
be considerab[~
higher
than
rke boiling lcmpcraturc
q'
/he rolt4rion in ri~riiatnr
without
ruusing
the
solution to
boil. Rcmovul (f
[he
rclliiator
cap
while engine is hot and pressure is high will
rouse the
solution
lo
boil instrmtar~~nus!~ rrnd possibly
with explo.~ivc. forc~: spewit~g the
sokrtion nvpr
mgirte,
fender~, and person
removing
cup. If the
sdution
c>onzai11.~
in*mnhl~>
anti
-ji.eez~, surh
ns
ulr nhol.
I
here
1s
also the pt).~sibib(v of
ccausin;~
u serious fire.
When
removingJilIcr
cap, rotate
cap
toward
Iefi
wry
,slowly:
i j
hissinx of
wptir is
mc.uunt~rr.d,
:i~htt.n
czty z m m ~ d i i l ~ ~ l y
and wait
for
~y.Ttem
ro
cool
suj/ir.irnl+ ro
allow
remnval
off
cap.
A j e r
pressure
in s~rtetvt
has been
relieved, turn
cap more forcibly
10
IBJ
r~nd
r ~ ~ ~ ) i ~ ~ v r .
Ttitrr
cdp d l
f l t ~
way
to
righr when installing. 11 should
nor
be necessary
lo
check
cwlunl levrl unless lemperature pauge shows
over-heating, and
then
p r r A
until thngine n
slopp~~d
a d
alluwcd
to
cool
to normal.
The pressurc
type
radiator liIIer cap cotltains
a blow
off of pressure valve
and
a kacuurn or
atmospheric
valve.
The pressure
valve it
held against its
seal
by
a
spring of prz-determined strength
which protects the
radiator by relieving the pressure
if
an extremu
case
of'
internal pressure should exceed
that
for which
the
cooling
system i s designed.
The vacuum valve is held
against its
seat
by a light spring which permits opening
af the valve to relieve vacuum created in
the
cystem
when it cooIs off and which othenvise niight cause the
radiator
to
collapse.
W A f ER PUMP-8 CYLINDER
The centrifugal-type
water
pump, dhider, inter~lal