1977 DATSUN PICK-UP air condition

Condition

POOR
FUEL
ECONOMY

Se
the

xplanation

of
the
pow
r

dec

Oth
n

PROBLEM
IN

OTHER

FUNCTIONS

D
cr
d

oil

p
ssure

Excessive
wear
on
the

sliding

parts

Scuffing
of

sliding

parts

Floor

temperature
too

high
California

only
Engine
Tune

up

Probable
cause

Exceeding
idling
revolution

Inoperative
acceleration
recovery

Fuel

leakage

Malfunction
of
B

C
D
D

Malfunction
of
A
r
C
air

cleaner

Inadequate
oil

quality

Overheat

Worn

oil

pump
regulator
valve

Functional
deterioration
of
oil

pump

Blocked
oil
f1lter

Increased
clearance
in
various

sliding
parts

Blocked
oil
strainer

Inoperative
oil

gauge
pressure
switch

Oil

pressure
decreases

Improper

quality
or
contamination
of

oil

Damaged
air
cleaner

Overheat
or
overcoal

Improper
fuel
mixture

Decrease
of
oil

pressure

Insufficient
clearances

Overhea
t

Improper
fuel

mixture

Problem
in

fuel

system
Refer
to

Inspec

tion
of
Fuel

System

Problem
in

ignition
system
Refer
to
In

spection
of

Ignition
System

ET33
Corrective
action

Adjust
it

to
the

designated
rpm

Adjust
it

Repair
or

tighten
the
connection
of

fuel

pipes

Adjust

Check
and

replace

Use
the

designated
oil

Previously
mentioned

Disassemble
oil

pump
and

repair
or
renew
it

Repair
or

replace
it

with
a

new
one

Renew
it

Disassemble
and

replace
the
worn

parts
with

new
ones

Oeanit

Replace
it
with
a
new
one

Previousiy
mentioned

Exchange
the
oil
with

proper
one
and

change
element

Change
elemen
t

Previously
mentioned

Check
the
fuel

system

Previously
mentioned

Readjust
to
the

designated
clearances

Previously
mentioned

Check
the
fuel

system

Check
and

repair

Check
and

repair

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

r

Engine
Mechanical

INSPECTION
AND
REPAIR

PREPARATION
FOR
INSPECTION

CYLINDER
HEAD
AND
VALVE

CHECKING
CYLINDER
HEAD
MATING

FACE

VALVE
ASSEMBLY

VALVE
SPRING

ROCKER
ARM
AND
VALVE

ROCKER

PIVOT

VALVE
GUIDE

VALVE
SEAT
INSERTS

CAMSHAFT
AND
CAMSHAFT

BEARING

CAMSHAFT

BEARING
CLEARANCE

VALVE
TIMING

CAMSHAFT
ALIGNMENT

CYLINDER
BLOCK

HOW
TO
MEASURE

CYLINDER
BORE

CYLINDER

BORING

PREPARATION
FOR

INSPECTI
N

I

Before

cleaning
check

for

signs

of
water

and
oil
leaks
in

cylinder
block

and

head

2
Clean
oil
carbon

deposits
and

sealant
from
an

parts
Remove

gasket

3
Clean
all

oil
holes
with
solvent

and

dry
with

compressed
air

Make

sure
that

they
are

not
restricted

CYLINDER
HEAD

AND
VALVE

CHECKING
CYLINDER

HEAD

MATING
FACE

EM407

Fig
EM

34
Cylinder
head
CONTENTS

EM
8

EM
B

EM
8

EM
8

EM
9

EM
lO

EM
l0

EM
11

EM

12

EM
12

EM
12

EM
13

EM

13

EM
13

EM
14
PISTONS
PISTON
PINS
AND

PISTON
RINGS

CONNECTING
ROD

CRANKSHAFT

BUSHING
AND
BEARING

MEASUREMENT

OF
MAIN

BEARING

CLEARANCE

MEASUREMENT
OF

CONNECTING
ROD

BEARING
CLEARANCE

FITTING

BEARINGS

MISCELLANEOUS
COMPONENTS

CRANKSHAFT
AND

CAMSHAFT

SPROCKETS

CHAIN

TENSIONER
AND
CHAIN

GUIDE

FLYWHEEL

FRONT
COVER
AND

REAR
OIL
SEAL

Note

Never

remove
camshaft
bear

ings
unless

you
have
a

Suitable

machine

or

boring
Camshaft
bear

ing
in
line
If

you
once
remove

camshaft

bearings
bearing
centers

will
come
out

o

alignment
reo

conditioning
is

very
difficult
with

out
center

borings

L
Make

a
v

isual
check
for
cracks

and
flaws

2

Measure
the
surface
of

cylinder

head
on

cylinder
block

side
for

warpage
If
it
is

found
to
be

beyond

the
limit

designated
below

regrind
the

affected
surface

with
a
surface

grinder

Fig
EM
35

Checking
cylinder
head

8JJrface

EM
8
Head
surface
flatnes

Standard

less
than
0
05

mm
0
0020
in
O
lmm

0
0039
in
EM
15

EM
16

EM
16

EM
17

EM
17

EM
1B

EM
18

EM
19

EM
19

EM
20

EM
20

EM
20

Maximum

VALVE
ASSEMBLY

Check
each
intake

and
exhaust

valve
for
worn

damaged
or
deformed

valve

caps
or
stems

Correct
or

replace

any
valve
that
is

faulty

2
Valve

face
or
valve
stem
end

surface

should
be
refaced
with
a
valve

grinder

10

L
I
I

I

EM109

Fig
EM
36
Intak
and

exhaust
valve

dimensions

Engine
Mechanical

TROUBLE
DIAGNOSES
AND

CORRECTIONS

Condition

I

Noisy
engine

Knocking
of
crankshaft

and
bearing

Knocking
of

piston

and

connecting
rod

Camshaft

knocking

Timing
chain
noise

Camshaft
and
valve

mechanism

knocking

Water

pump
knocking
Probable
cause

Loose
main

bearing

Seized
bearing

Bent
crankshaft

Uneven
wear

of

journal

Excessive
crankshaft
end

play

Loose
bearing

Seized

bearing

Loose

piston
pin

Loose

piston
in

cylinder

Broken

piston
ring

Improper
connecting
rod

alignment

Loose

bearing

Excessive
axial

play

Rough
gear
teeth

Broken
eam

gear

Improper
chain
tension

Worn
and
or

damaged
chain

Worn

sprocket

Worn
and
or

broken
tension

adjusting

mechanism

Excessive
camshaft
and

bearing
clearance

Improper
valve
clearance

Worn

adjusting
screw

Worn
rocker
face

Loose
valve
stem

i1
1
guide

Weakened
valve

spring

Seized
valve

Improper
shaft
end

play

Broken

impeller

II
Other
mechanical
troubles

Stuck
valve

Improper
valve
clearance

Insufficient
clearance
between
valve
stem

and

guide

Weakened
or

broken
valve

spring

Biting
or

damage
of
valve
stem

Poor

Quality
of
fuel

EM
31
Corrective
action

Replace

Replace

Repair
or

replace

Correct

Replace
cen
ter

bearing

Replace

Replace

Replace
pin
or

bushing

Recondition

cylinder

Replace

Realign

Replace

Replace
bearing
thrust

plate

Repair

Replace

Adjust

Replace

Replace

Replace

Replace

Adjust

Replace

Replace

Replace
guide

Replace

Repair
or

replace

Replace

Replace

Adjust

Clean
stem
or
ream
guide

Replace

Replace
or
clean

Use
ood
fuel

Condition

Seized
valve

seat

Excessively
worn

cylinder
and

piston

Faulty
connecting

rod

Faulty
crankshaft

bearing
Engine
Mechanical

Probable

cause

Improper
valve

clearance

Weakened
valve

spring

Thin
valve
head

edge

Narrow
valve
seat

Overheating

Over

speeding

Stuck
valve

guide

Shortage
of

engine
oil

Dirty

engine
oil

Poor

quality
of
oiL

Overheating

Wrong
assembly
of

piston
with

connecting

rod

Improper
piston

ring
clearance

Broken

piston

ring

Dirty
aii

cleaner

Mixture
too
rich

Engine
over

run

Stuck
choke
valve

Overchoking

Shortage
of

engine
oil

Low
oil

pressure

Poor

quality
of

engine
oil

Rough
surface
of

craokshaft

Clogged
oil

passage

Bearing
worn
or

eccentric

Bearingimproperly
assembled

Loose

bearing

Connecting
rod

alignment
incorrect

Shortage
of

engine
oil

Low

oil

pressure

Poor

quality
of

engine
oil

Craokshaft

journal
worn
or

out
of
round

Clogged
oil

passage
in

crankshaft

Bearing
worn

or
eccentric

Bearing
improperly
assembled

Eccentric

craokshaft

or

bearing

EM
32
Corrective
action

Adjust

Replace

Replace
valve

Reface

Repair
or

replace

Drive
at

proper
speeds

Repair

Add
or

replace
oil

Clean

crankcase

replace
oil
and
oil
niter

element

Use

right
oil

Repair
or

replace

Repair
or

replace

Adjust

Replace

Clean

Adjust

Drive
at

proper
speeds

Clean

and

adjust

Start

correct

way

Add
oiL

Correct

Use

proper
oil

Grind
and

replace

bearing

Clean

Replace

Correct

Replace

Repair
or

replace

Add
or

replace

Correct

Use

proper
oil

Repair

Clean

Replace

Correct

Replace

The

pump
shaft
is

supported
by
a

double
row

of
ball

bearings

press
fit
in

an
aluminum
die
cast

pump
body
The

bearings
are

permanently
lubricated

and
sealed

to

prevent
loss
of
lubricant

and

entry
of

dirt

The

pump
is

provided
with
an

impeller
which
turns
on
a
steel

shaft

The

steel
shaft
rotates

together
with

the

torque

coupling
wheeL
The
volute

chamber
is
built
in
the

engine
front

cover

assembly

The
inlet
of
the

pump
is

connected

to

the
radiator
s
lower
tank

by
a
hose

i

o

CQ047

Fig
CO
2
Water

pump
and

engine

front
cover

REMOVAL
AND

INSTALLATION

Removal

in
to
a
clean

con

assembly

I

CQ048

Fig
CO
3
Removing
water

pump

Installation

1
Be

sure
to
clean
the

gasket
sur

faces
in
contact
with

pump
and
front

cover

Always
use
new

gaskets
when

installing

pump
assembly
Be
sure
to

tighten
bolts
Cooling
System

Tightening

torque

0
4
to
0
5

kg
m

3
0
to
3
6
ft
lb

2

Fill

cooling
system
and
check
for

leaks
at

pump

3

Install
fan
blade
and

tighten
at

taching
bolts

securely
Install
belt
and

adjust
for

specified
tension

4

Operate
the

engine
at
fast

idling

and
recheck
for
leaks

5
Install
fan
shrouds

Note
Ensure
that
clearance
between

shroud
and
Can
is

even
at

any

place

DISASSEMBLY

Water

pump
is

made
of
aluminum

and
its

bearing
outer
race
is
of
a

press

fit

type
For
this

reason
water

pump

should
not
be
disassembled

INSPECTION
AND

ADJUSTMENT

Inspection

Inspect
pump
assembly
for
the

fol

lowing
conditions
and

replace
if
nee

essary

1

Badly
rusted
or
corroded

body
as

sembly
and

vane

2

Excessive
end

play
or

roughness
of

bearings
in

operation

3
Reduced

cooling
efficiency
due
to

deteriorated
silicone
oil

4
Oil

leakage
in

torque
coupling
Adjustment

Fan

belt
should
be

properly
ad

justed
at
all
times
A

tight
belt
causes

wear
of

alternator
and
water

pump

bearings
A
loose
belt

brings
about

improper
cooling
fan
water

pump

and
alternator

operation

Check
the
belt
slack
between
alter

nator
and
fan

pulley
by
force
of
10

kg

22
lb

Slackness
of
fan
belt

8
to
12

mm

0
31
to
0
47
in

If

adjustment
is

necessary
loosen

bolt

retaining
alternator

adjusting
bar

to
alternator
Move

alternator
toward

or

away
from

engine
until
the
correct

tension
is
obtained

TORQUE
COUPLING

Except
air

conditioner

equipped

models

The

torque
coupling
keeps
the
fan

speed
at
2
500

rpm
rated
or
below

to

conserve
horsepower
at

high
engine

speed
It
also

helps
reduce
fan
noise
to

a
minimum

during
high
speed
opera

tion

This
unit
is
filled
with
a

special

silicone
oil
used
as
a

fluid

coupling

which
controls
the

fan

speed
Silicone

oil

can
not
be

replenished

1

Torque
coupling
wheel

2

Torque
coupling
cover

3

Torque
coupling
bearing

4
Pulley

5
Water

pump

C0060

Fig
CO
4
Sectional
view
of

torque
coupling
and
water

pump

00
3

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