engine coolant DATSUN PICK-UP 1977 Service Manual

Engine
Tune

up

BASIC
MECHANICAL
SYSTEM

ADJUSTING
INTAKE
AND
EXHAUST

VALVE
CLEARANCE

CHECKING
AND

ADJUSTING
DRIVE

BELT

RETIGHTENING
CYLINDER
HEAD
BOLTS

MANIFOLD
NUTS
AND
CARBURETOR

SECURING
NUTS

CHECKING
ENGINE
OIL

REPLACING
OIL
FILTER

CHANGING
ENGINE

COOLANT

ADJUSTING
INTAKE

AND

EXHAUST

VALVE
CLEARANCE

Note
After

tightening
cylinder
head

bolts

adjust
intake

and
exhaust

valve
clearances

Valve
clearance

adjustment
is

impossible
when
the

engine
is
in

oper

ation

1
Loosen

pivot
locking
nu
t
and

turn

pivot
screw
until
the

specified

clearance
is
obtained
while
cold

Using
service

tool

tighten
pivot

locking
nut

securely
after

adjustment

and
recheck
the
clearance

2
Warm

up
engine
for
at
least

several
minutes

and

stop
it
Measure

valve
clearance
while
hot
If
out
of

specifications
adjust

Unit
mm
in

Intake
0
20

0
008

Cold

Exhaust
0
25
0

010

Intake
0
25

OmO

Wann

I
Exhaust

0
30
0

012

STl
064000

I

ET009

Fig
ET

5

Adjusting
valve

clearance
CONTENTS

ET
7
PERMANENT
ANTI
FREEZE

COOLANT

CHECKING
COOLING
SYSTEM
HOSES

AND
CONNECTIONS

INSPECTION
OF

RADIATOR
CAP

COOLING
SYSTEM
PRESSURE
TEST

CHECKING
VACUUM

FITTINGS
HOSES

AND
CONNECTIONS

CHECKING
ENGINE
COMPRESSION

COMPRESSION
PRESSURE
TEST

TEST
RESULT
ET
7

ET7

ET
B

ET
B

ET
B

CHECKING
AND

ADJUSTING

DRIVE

BELT
ET

B

ET

B

ET
B

ET
B

ET

B

ET
9

ET
9

ET
9

2

Normal
drive
belt
deflection
is

8

to
12
mm

0
315
to
0
472

in
when

moderate
thumb

pressure
is

applied

midway
between

pulleys

1
Check
for

cracks
or

damage
Re

place
if

necessary

Compressor
pulley

8
to
12
mm
0
315
to
0
472
in

Idler

pulley

Water

pump
pulley

8
to
12
mm

0
315
to
0
472
in

Air

pump
pulley

Alternator

AC456

Fig
ET
6
Driue
belt
tension

RETIGHTENING

CYLINDER
HEAD

BOLTS
MANIFOLD

NUTS
AND

CARBURETOR

SECURING

NUTS
Tightening
torque

Cylinder
head
bolts

1st

turn

4

0

kg
m
29
ft
Ib

2nd
turn

6
0

kg
m

43
ft
Ib

3rd
turn

6
5
to

8
5

kg
m

47

to
61
ft
lb

Refer
to
the

following
tightening

torque
specifications

ET
7

r

ManifolJ
nuts

I

2
to
1
6

kg
m

8
7
to
I

6
ft
lb

Carburelor
nuls

0
5
to
1
0

kg
m

3
6
to
7
2
fl
tb

Fig
ET
7
Tightening
s

quence

CHECKING
ENGINE

OIL

Check
if
oil
is
diluled
with
water

or

gasoline
Drain
and
refill
oil
if

necessary

Notes

a
A

milky
oil
indicates
the

presence

of

cooling
water
Isolate
the
cause

and
take
corrective
measure

b
An
oil
with

extremely
low

viscosity

indicates
dilution
with

gasoline

2
Check
oil
level
If
below
the

specified
level

raise
it

up
10
the
H

level

Engine
oil

capacity

including
oil

filter

Maximum
H
leven

4
3
liters

4

MUS
qt
3
Y

Imp
qt

Minimum
L

level

3
3
liters

3
f
US

qt
2
U

Imp
ql

REPLACING
OIL

FILTER

The
oil
mter
is

a

cartridge
type
and

can
be
removed

using
Oil
Filter

Wrench
STI9320000

I
Check
for
oil
leaks

past
gasketed

flange
If

leakage
is

found

retighten

just
enough
to

stop
leakage
If

retight

ening
is

no

longer
effective

replace

mter
as
an

assembly
Engine
Tune

up

2
When

installing
oil

filter

tighlen

by
hand

Note
Do
not

overtighten
oil

flIt

lest

leakage
should
occur

CHANGING
ENGINE

COOLANT

PERMANENT
ANTI
FREEZE

COOLANT

Permanent
anti

freeze
coolant
is
an

ethylene
glycol
base

producl
conlain

ing
chemical
inhibilors
10

protect
the

cooling
system
against
corrosion

The
anti
freeze
does
not
contain

any

glycerine
ethyl
or
methyl
alcohol

It
will
not

evaporate
or
boil

away
and

can
be
used
with
either

high
or
low

temperaturethennoslat

It

flows

freely
transfers
heat
effi

ciently
and
will

not

clog
passages
in

the

cooling
system

The
anti
freeze
must
not
be
mixed

with
other

products

This
coolant
can
be
used

through

out

the
seasons
of
the

year

Whenever
coolant
is

changed
the

cooling

syslem
should
be
flushed
and

refilled
with
a

new
coolant

Check
the
level
See
the
instruc

lions
furnished

by
the
manufacturer

for
the
mixture
ratio

of
anti
freeze
10

water

CHECKING

COOLING

SYSTEM
HOSES

AND
CONNECTIONS

Check
hoses
and

fittings
for
loose

connections
or
deterioration
Re

tighten
or

replace
if

necessary

INSPECTION
OF

RADIATOR

CAP

Apply
reference

pressure
0
9

kg
cm2
13

psi
1
to
radiator

cap
by

means
of

a

cap
tester
to
see
if
it
is

satisfactory
Replace
cap
assembly
if

necessary

ET
8
Fig
ET
fJ

Teltill
l
rod
ioto

cop

COOLNG
SYSTEM

PRESSURE
TEST

With
radiator

cap
removed

apply

reference

pressure
1

6

kg
cm2
23

psi
to
the

cooling
system
by
means

of
a
lesler
to
detect

any
leakage

Water

capacity

Without
heater

7
4
liters

7
U
US

qt
6
f

Imp
qt

With
heater

8
0
liters

8
f
US

qt
7

Imp
qt

CHECKING
VACUUM

FITTINGS
HOSES

AND
CONNECTIONS

Check
the
condition
of

filtings
and

hoses

Retighten
or

replace
if
neces

sary

All
vacuum
hoses
can
be
identified

by
colors

White
line

Vacuwn
tube
to
carburetor
E

G
R

Tube

Vacuum
tube
to
thermal
vacuum

valve

Thennal
vacuum
valve
to
E
G
R

control
valve

Ignition
Switch
Position
START

Detector
Drive
Counter

E

G
R

Warning
Lamp
ON

a
After

completing
inspection
of

E
G
R
control

system
be
sure
to

reset
odometer
of
detector
drive

counter
to
zero

b
This
item

applies
to
620
models

except
those
bound
for
California

and
Canada

3
With

engine
stopped

inspect

E
G
R
control
valve
for

any
indication

of

binding
or

sticking
by
movirig
dia

phragm
of
control
valve

upwards
with

fmgers
Engine
Tune

up

ON

Below

50

000
counts
Above

50
000
counts

OFF
ON

4
With

engine
running
inspect

E
G
R
control
valve
and
thermal

vacu

um
valve
for

normal

operation

I
When

engine
coolant

tempera

ture
is

low

Make
sure
that
E
G
R
control
valve

does

not

operate
when

engine
speed
is

increased
from

idling
to
3
000
to

3
500

rpm

Place

fingers
on
the

diaphragm
of

E
G

R
control
valve
to
check
for
valve

operation

2

When

engine
coolant

tempera

ture
is

high

I
Make
sure
that
E
G
R

control
valve

operates
when

engine

speed
is
in

creased
from

idling
to
3
000

to

3

500

rpm
Place

fingers
on
the

diaphragm
of
E

G
R

control
valve

to
check
for
valve

operation

2
If
E

G
R

control
valve
does
not

operate
check
as
follows

Disconnect
one
end
E
G
R
control

valve
side
ofvacuum
hose
connect

ing
thermal
vacuum
valve
to

E
G
R
EC253

Fig
ET
40

Checking
E
G
R
control
valve

control
valve

Increase

engine
speed
from

idling
to

3

000
to
3
500

rpm

Make
sure

that
thermal
vacuum

valve
is

open
and
that
carburetor

vacuum
is

present
at
the
end

E
G
R
control
valve

side
ofvacu

urn
hose

If
vacuum
is
weak
or
not

present
at

all

replace
thermal
vacuum
valve
If

vacuum
is

present
replace
E

G
R

con
trol
valve

ET
21
EC254

Fig
ET
41

Checking
thermal

vacuum

valw

If

any
difficulty
is
encountered
in

judging
the
condition
of

any

compo

nent

during
above

inspection
check

the

questionable
component
independ

ently
as

follows

E
G
R
control
valve

Dismount
E
G
R
control
valve

from

engine

I

Apply
vacuum
to
E
G
R
control

valve

referring
to
the

following
figure

If
the
valve
moves
to

full

position
it
is

normal

E
G
R
control

valve
will
remain

open
for

more
than
30

seconds
after

vacuum
has
cut
off

0

r11

hC

J

ET152

Fig
ET
42

Checking
E
G
R
control

VGlve

2

Visually
check
E
G
R
control

valve
for

damage
wrinkle
or
deforma

tion

3
Clean
the

seating
surface
of

E
G
R
control
valve
with

a
brush
and

compressed
air

and
remove

foreign

matter
from
around
the

valve
and

port

r
EC350

Fig
ET
43

Cleanill
l
E
G
R
control

lJ
Jlue

Thermal
VBCuum
valve

Dismount
thermal
vacuum
valve

from

engine

Note
Before

dismounting
drain
e

gine
coolant
from

engine

Apply
vacuum
to
thermal
vacuum

valve
and
check
to
be
sure
that
ther

mal
vacuum
valve

opens
or
closes
in

response
to

engine
coolant

tempera

lurt
i1
i

iYCl
lt
lt
U

Thermal
vacuum
valve
should

open

at
a

temperature
of
57
to
630C
134

to
1450F

completing
the
vacuum

passage

Note
Do
not
aUow
water
to

get

inside
the
thermal
vacuum
valve

EC
242

Fig
ET
44

Checkill
lthermallXlCuum

valve
Engine
Tune

up

CHECKING

EVAPORATIVE

EMISSION
CONTROL

SYSTEM

Vapor
Rnes
and
fuel

vepor

control
valve

Checking
fuel
tank

vapor

liquid

separator
and

vapor
vent
line

I
Check
all
hoses
and
fuel
tank

roler

cap

2
Disconnect
the

vapor
vent
line

connecting
carbon
canister
to

vapor

liquid
separator

3
Connect
a
3
way
connector
a

manometer
and
a
cock
or
an

equiva

lent
3
way

charge
cock
to

the
end
of

the
vent
line

4

Supply
fresh
air
into
the

vapor

vent
line

through
the

cock
little

by
little
until

pressure
becomes
368

mmH20
14
5
inH20

5

Shut
the
cock

completely
and

leave
it
unattended

6

After
2
5
minutes

measure
the

height
of
the

liquid
in

the
manometer

7

Variation
of

height
should
remain

with
25

mm
l20
0
98
inH20

8
When
filler
cap
does

not
close

completely
the

height
should
drop
to

zero
in

a
short
time

9
I
f
the

height
does
not

drop
to

zero
in

a
short
time
when
filler

cap
is

removed
it
is
the

cause
of
a

stuffy

hose

Note
In

case
the

vent
line

is
stuffy

the
breathing
in

fuel
tank
is
not

thoroughly
made

thl
causing
in

suffICient

delivery
of
fuel
to

engine

or

vapor
lock
It
must
therefore
be

repaired
or

replaced

3
way
connectoT

36
mmH20

14
5
inH20

c

s
I

W

@

Carbon
canister

r

EC786

Fig
ET
45

Checking
evaporative
emission
control

By
tem

Checking
carbon
canister

purge

control

valve

Check
for
fuel

vapor
leakage
in
the

distributor
VC
line
at

diaphragm
of

carhon
canister

purge
control
valve

To
check
for

leakage

proceed
as

follows

1
Disconnect

rubber
hose
in

the

line
between
T
connector
and
carbon

canister
at
T

connector

2
Inhale
air
into

the

opening
of

rubber
hose

running
to
VC
hole
in

carbon
canister
and
ensure
that
there

is

no
leak

ET

22
I

I

L

I

ET349

Fig
ET
46

Checking
carbon
cani
ter

purge
control
valve

Condition

ENGINE
POWER
NOT

UP
TO
NORMAL

Low
compression

Ignition
system
out
of

order

Fuel

system
out

of

order

Air
intake

system
out

of
order

Emission
control

Overheating

O

cooIing

Others
Engine
Tune

up

Probable
cause

Incorrect

iSnition
timing

Damaged

spark
plugs

Worn
distributor

points

Malfunction
of
choke

system

Clogged
fuel

pipe
or

floating
valve

Dirty
or

clogged
fuel
strainer

Fuel

pump
will
not
work

properly

C10ssed
carburetor

jets

Malfunction
of
altitude

compensator

CIOJBed
air
cleaner

Ail

inhaling
from
manifold

gasket
or

carburetor

gasket

Malfunction
of

E
G
R
valve

Stick
E
F
E

valve
shaft

Insufficient
coolant

Loose
fan
belt

Worn
or
oiled
fan
belt

Inoperative
thermostat

Worn
water

pump

Clogged
or

leaky
radiator

Worn
radiator
filler

cap

Ail

in

cooling
system

Improper
engine
oil

grade

Incorrect

ignition
timing

Clossed
carburetor
lean
mixture

Disconnected
altitude

compensator
hOlle

Inoperative
thermostat

Improper
octane
fuel

L

j
tire

pressure

Dragging
brake

Clutch

slipping

ET

30
Corrective
action

Previously
mentioned

Adjust

Clean

adjust
or

replace
plull

Dress

or

replace
points
Also
check

condenser

Adj
lst

Clean

Replace

Repair
or

replace

Disassemble
and
clean

Check
and

replace

Replace
element

Replace
gasket

Check
and
replace

Repair

Replenish

Adjust
fan
belt

Replace

Replace

Replace

Flush

repair
or

replace

Replace

Retighten
each

part
of

cooling
system

Replace
with

proper
grade
oil

Adjust

Overhaul
carburetor

Connect

Replace

Replace
with

specified
octane
fuel

Inflate

to

specified

pressure

Adjust

Adjust

Except
transistor

ignition
system

r

I

I

PRELIMINARY
CLEANING
AND

INSPECTION

DISASSEMBL
Y

PRELIMINARY

CLEANING
AND

INSt

ECTION

Before

disassembling

engine
note

the

following

I
Fuel

oil
or
water

may
leak

past

cylinder
head
and
block
Prior
to

disassembling
check

cylinder
head

1
1ltermal
vacuum
valve

2
Check

valve

3
Altitude

compensator

in

air
cleaner

4
Air

gallery
pipe

S

Auto
choke

6
Automatic

temperature

control
air

cleaner

7
Anti
8ackfire
valve
A
B

valve

8
Boost
Controlled

Deceleration

Device
Bee
D
D

9
P
c
v

valve

to
Air
relief
valve

11
E

G
R

control
valve

12
B
C
D
D

control
valve
and

solenoid
valve

13

Emergency
air

relief
valve

14
Air

pump
air
cleaner

IS
Carbon
canister

16
Air
control

valve

11
Air

pump
Engine
Mechanical

ENGINE

DISASSEMBLY

CONTENTS

EM
4

EM
4
PISTONS
AND
CONNECTING
RODS

CYLINDER

HE
AD
EM
7

EM
7

front
chain

cover
oil

pan
and
oil

filter

gaskets
lInd
crankshaft
and
water

pump
seals
for

signs
of

leakage
past

their

gasketed
surfaces

2
Check
carburetor
and

fuel

pump

for
condition
fuel
hoses
for

deteriora

tion
cracks

or

leakage
of
fuel

past

their

jointed
or
connected

surfaces

Fig
EM

0
Emiuion
control
devic
s

California
mod
18
E
T366

3
Remove

carburetor
air

cleaner

Remove
fresh

air
duct

Disconnect
hot
air
duct
from

air

cleaner

Disconnect
air

cleaner
to
air

pump

hose
at
air

cleaner

Disconnect
air

cleanef
to
rocker

cover

hose
at
rocker
cover

Disconnect

air
cIeaner

to
air

con

trol

valve
hose
at
air

cleaner
Cali

fornia

models

only
Disconnect
air

cleaner
to
A

B
valve

hose
at
air

cleaner

Disconnect
air

cleaner
to

related

part
vacuum
hoses
at
air

cleaner

Loosen
air

cleaner
band
bolt
and

remove
carburetor
air

cleaner
as

sembly
from

carburetor

4

Plug
up
carburetor
air

horn

to

prevent
entry
of

foreign
matter

5

Remove

alternator
drive

belt

alternator
and

alternator
bracket

EM
4
6

Remove
air

pump
drive

belt
cool

er

compressor
and
idler

pulley
if

so

equipped

7
Remove
starter
motor
from
trans

mission

8

Visually

inspect
cylinder
head

cylinder
block
rocker
C
Ner

front

chain
cover
oil

pan
and
all
other
outer

parts
for
oil
water
and
fuel
leaks

breakage
or

missing
parts
such

as
bolts

and
nuts

9

Check

piping
and
electrical
cir

cuits
for
deterioration

breakage
fit

tings
discontinuity
or
insulation

DISASSEMBLY

To

remove

engine
from
vehicle

refer
to

the
instructions
under
the

Engine
Removal

and
Installation

ER
section

I

Remove
transmission
from

en

gine

2
Remove

clutch

assembly
from

flywheeL

3

Thoroughly
drain

engine
oil
and

coolan
t

by

removing
drain

plugs

Store

engine
oil
and

coolant
if

they

are

to
be

used

again

4
Place

engine
assembly
on

engine

stand

I

Remove

cooling
fan

2

Remove

right
engine

mounting

bracket

3

Remove
oil
filter
with
Oil

Filter

Wrench
STI9320000

4

Remove
oil

pressure
swi

tch

5

Install

engine
attachment
to

cylinder
block

utilizing
bolt

holes
in

alternator

bracket
and

water
drain

hole

6
Set

engine
on
stand

Engine
Attachment

ST05260001

Engine
Stand

ST050I

SOOO

DESCRIPTION

COOLANT
LEVEL

DRAINING
AND
FLUSHING
THE

COOLING
SYSTEM

WATER
PUMP

REMOVAL
AND

INSTALLATION

DISASSEMBLY

INSPECTION
AND
ADJUSTMENT

TORQUE
COUPLING

REMOVAL
AND

INSTALLATION

DESCRIPTION

The

cooling
system
is
of
the
con

ventional

pressure
type
A

centrifugal

pump
installed
on

the

timing
chain

cover
serves
to
circulate
the

coolant

The

pressure
type
radiator
filler

cap

installed
on
the
radiator

operates
the

cooling
system
at

higher
than

atmos

pheric
pressure

The

higher

pressure
raises
the

boiling
point
of
the

coolant
and
in
Cooling
System

COOLING
SYSTEM

CONTENTS

CO
2

CO
2
OISASSEMBL
Y

INSPECTION

TEM
COUPLlNG

INSPECTION

THERMOSTAT

REMOVAL
AND

INSTALLATION

INSPECTION

RADIATOR

REMOVAL
AND

INSTALLATION

INSPECTION
CO
2

CO
2

CO
3

CO
3

CO
3

CO
3

CO
4

creases
the

cooling
efficiency
of

the

radiator

When
the

thermostat
is
closed

the

coolant
remains
in
the

cylinder
head

and

block
for
swift

warming
up
of
the

engine
After
it
reaches

normal

oper

ating

temperature
the

coolant
circu

lates

through
the
radiator

The

cooling
fan

drive
is
of
a

coupling
type

COOLANT

LEVEL

The

coolant
level
should

be
check

ed

and
maintained
at
SO

mm
1
97
in

below

the

upper
face
of
filler

neck

when
the

engine
is
cold
C0055

Fig
CO

I
Cooling

ry
lem

Caution

To
avoid
serious

personal

injury
never
remove
I3diator

cap

quickly
when

engine
is
hot
Sudden

release
of

cooling

system
pressure
is

very

dangerous

CO
2
CO
4

CO
4

CO
4

CO
5

CO
5

CO
5

CO
5

CO
5

CO
5

CO
6

If
it
is

necessary
to
remove
radiator

cap
wben
radiator
is
hot
turn

cap

slowly
counterclockwise

to
the
r

step
After
all

pressure
in
the
cool

ing
system
is
released
tom

cap

passing
the

stop
and
remove
it

DRAINING

AND
FLUSHING

THE

COOLING

SYSTEM

To
drain

the

cooling
system
re

move
radiator

cap
release
drain

cock

at
the
bottom

of
radiator
and
drain

plug
on

the

right
side
of

cylinder

block
If
the

heater

system
is
installed

set
heater

temperature
control
valve
to

open
position
After
the

coolant
is

drained

completely
close
drain

cock

and

plug
and
refill
the

system
with

clean
soft
water

WATER
PUMP

The

water

pump
cooling
fan

pulley

and

torque

coupling
are

a
unitized

construction

The
water

pump
is
of

a

centrifugal

type
which

is
mounted
on
the

engine

front
cover

REMOVAL
AND

INSTALLATION

To

replace
the

torque

coupling

follow
the

same

procedure
as
in
the

water

pump
The

torque
coupling
can

not
be

separated
from
the
water

pump
Cooling
System

DISASSEMBLY

The

torque
coupling
is

so

designed

that
it

can
not
be

disassembled
INSPECTION

Inspect

torque
coupling
for
oil

leakage
If

necessary

replace

TEM

COUPLl
G

For
air
conditioner

equipped
models

Tem
coupling
is

a

type
of
fan

coupling
which
is

provided
with
a

temperature
control

system

The
conventional

coupling

always

slips
the
fan
at

a
high

speed
under

a

constant
ratio

regardless
of

the

engine

cooling

requirement

The

slipping
ratio

of
the
Tern

coupling
however

is

properly
changed

with
the

cooling
requirement

ON
denotes

that

cooling
is
re

quired
and
the
fan

operates
up
to

about

2
150

rpm
When

high

cooling
is

not

required

during
cold
season
with

the

engine
warmed

up
etc
the

oper
w

6
I

1
Bi
metal

thermostat

2

Slide
valve

3
Reserve
chamber

for
OFF

4

Bearing

5

Driving
chamber
for

ON

6

ouplingpart
labyrinth

coon

Fig
CO
5
CrQM
sectional
view

of
Tem
coupling

ation
is

placed
under

OFF
condition

and
the
fan

slips
at
about

1
650

rpm

The
coiled
bimetal
thermostat

installed
on

the
front
center

portion
of

the
Tem

coupling
detects

temperature

of
air

passing

through
the

radiator

The
air

temperature
is

directly

relative
to
the

engine
coolant

tempera

ture
and
the
inside

slide
valve
is

opened
or
closed

as

required
and
thus

the
ON
OFF

control
is

performed

When
the
air

temperature
rises

the

bimetal
is

expanded
and
the

valve
is

opened
silicon
oil
is
forwarded

to
the

groove
that
transmits

torque
and
the

CO
4
system
is

placed
under
ON

con

dition

When
the

valve
closes
silicone
oil
is

not

supplied
to
the

driving
chamber

oil
in

the

driving
chamber
is

accumu

lated
on

periphery
due
to
the

centrif

ugal
force
and
led

into
the
reserve

chamber
Now

oil
is

eliminated
from

the

driving
chamber

and
the

system
is

placed
under
OFF
condition

With
this

system
when
fan

cooling

is
not

required
the

output
loss
is

minimized

and
noise

can
be
far

reduced

Conventional

COUplin9

WATER
PUMP
SPEED

F

Z

Tern

coupling

WATER
PUMP

SPEED

C0029

Fig
CO
6
Characteristic

of

Tern
coupling

INSPECTION

Check
Tem

coupling
for
oil

leakage

or
bend
of
bimetal

If
the
above

symptoms
are
found

replace
it
with

a
new
one
as
an

assembly

THERMOSTAT

A
wax

pellet
type
thermostat
is

mounted
in
the
thermostat

housing
at

the

cylinder
head
water
outlet

The
function
of
the
thermostat
is

to
control
the

flow
of
coolant
facili

tating
fast

engine
warm

up
and

regu

lating
coolant

temperature
The
ther

mostat
is

designed
to

open
and
close
at

predetermined
temperatures
and
if

not

operating
properly
should
be

re

moved
and
tested
as
described
below

REMOVAL
AND

INSTALLATION

I

Drain
coolant

partially

2
Disconnect

upper
radiator
hose
at

water
outlet

3

Remove
bolts

and
remove
water

outlet

gasket
and
thermostat
from

thermostat
housing

Fig
CO
7

Removing
therm06t
t
Cooling
System

4

After
checking
thermostat
re

install
with

a
new

housing
gasket
in

place

5
Reinstall
water

outlet

6

Replenish
coolant
and
check
for

leaks

INSPECTION

A

sticking
thermostat
will

prevent

the

cooling
system
from

functioning

properly
If
the
thermostat
sticks
in

the

open
position
the

engine
warms

up
very
slowly
If
the
thermostat

sticks
in

the
closed

position
over

heating
will
result
Therefore
the
ther
mostat
should
be

inspected
to

make

sure
that
it
is
in

good
condition

1
Measure
coolant
temperature

when
thermostat
valve
starts
to

open

2
Measure
the
maximum
lift

of

thermostat
valve

Fig
CO
S

Impecting
therm06t
t

Temperate
Frigid
Tropical

type

type
iype

Valve

opening

80
5
to
83
5
86
5
to
89
5
75

to
78

temperature

177
to
183
187
to
193

167
to
172

oC
OF

Maximum

valve
lift
8
95
8
1
00
8
90

mm
oC

in
F
0
31
203

0
31
212
0
31

194

If
thermostat
does
not

operate
at

the
above

specified

temperature
it

must
be

replaced
because
it
cannot
be

repaired

RADIATOR

The
radiator
is

a
conventional
down

flow

type
having

top
and

bottom

tanks
to

distribute
the
coolant
flow

uniformly
through
the
vertical
tube
of

radiator
core

The

radiator
filler

cap
is

designed
to

maintain
a

pre
set

pressure
0
9

kg
cm2
13

psi
above

atmospheric

pressure

The
relief
valve

consisting
of

a

blow
off

valve
and
a

vacuum
valve

helps
to

prevent
the
coolant
from

boiling
by
giving

pressure
to
it
How

ever
when

the

pressure
is
reduced

below

atmospheric

pressure
the

vacu

um
valve
allows
air

to
re
enter

the

radiator

preventing
the
formation
of
a

vacuum
in
the

cooling
system

CO
5
On
models

equipped
with
auto

matic
transmission

the
oil
cooler
is

combined
with
the

radiator
to
cool

transmission
fluid

REMOVAL
AND

INSTALLATION

Drain
coolant
into
a
clean
con

tainer

2

Disconnect
radiator

upper
and

lower
hoses
On
models
with
auto

matic
transmissions
disconnect
cooler

inlet
and
outlet
lines
from
radiator

3

Remove
fan
shroud
retaining

bolts
and

remove
fan
shroud

4

Remove
front

grille

5

Remove
radiator
retaining
bolts

and
then

remove
radiator

upward

6
Install
radiator
in
the
reverse
se

quence
of
removal
Note
the
fol

lowing

I
Insert
hoses
in

their

positions

until

they
bottom

2
Ensure
that
arrow
marks
on

hoses
are

clearly
visible
from

upper

Condition

Loss

of
water

Poor
circulation

Corrosion

Overheating

Overcooling
Cooling
System

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Probable
cause

Damaged
radiator
seams

Leaks
at
heater
connections
or

plugs

Leak
at

water

temperature
gauge

Loose

joints

Damaged
cylinder
head

gasket

Cracked

cylinder
block

Cracked

cylinder
head

Loose

cylinder
head

bolts

Restriction
in

system

Insufficient
coolant

Inoperative
water

pump

Loose

fan
belt

Inoperative
thermostat

Excessive

impurity
in

water

Infrequent
flushing
and

draining
of

system

Inoperative
thermostat

Radiator
fin
choked
with
mud
chaff
etc

Incorrect

ignition
and
valve

timing

Dirty
oil
and

sludge
in

engine

Inoperative
water

pump

Loose
fan
belt

Restricted
radiator

Inaccurate

temperature
gauge

Impurity
in

water

Inoperative
thermostat

Inaccurate

temperature
gauge

CO
7
Corrective
action

Repair

Repair

Tigh
ten

Tighten

Replace

Check

engine
oil
for
contamination
and
refill

as

necessary

Replace

Check

engine
oil
in
crankcase
for

mixing

with

water

by
pulling
oil
level

gauge

Replace

Tighten

Check
hoses

for

crimps
and

clear
the

system

of
rust
and

sludge
by
flushing
radiator

Replenish

Replace

Adjust

Replace

Use
soft
clean
water
Rain

water
is
satis

factory

Cooling

system
should
be

drained
and

flushed

periodically
Permanent
anti
freeze

Ethylene
glycol
base
can
be

used

through

out
the

seasons
of
the

year
and

change

periodically
at
intervals
recommended

Replace

Clean
out

air

passage
thoroughly
by
using
air

pressure
from

engine
side
of
radiator

Adjust

Refill

Replace

Adjust

Flush
radiator

Replace

Use
soft
clean
water

Replace

Replace