flat tire DATSUN PICK-UP 1977 Service Manual

Page 42 of 537


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

Page 398 of 537


Condition

Brake
chatters

Brake

squeals

Pedal

pulsates

Brakes
fade

Brakes

drag

Unbalanced
brakes
Brake

System

Probable
cause

Groove

or
out
of

round
brake
drum

Loose

or
bent

brake

disc

Distorted
brake
shoes

or

pads

Grease
or
brake
fluid
on

linings

Dirty
or
scored
brake

drums

Distorted
brake
shoes
or
bent

support
plate

Weak
or
broken
brake
shoe

retaining
spring

or

return

spring

Glazed
or
contaminated
brake

lining

Out
of

round
or
off
center
drum

Brake
fluid
has
too
low

boiling
point

Use
of

improper
linings
or
brake

linings
are

contaminated

Brake
drums
are
out
of
round

Hydraulic
connections
master

cylinder
and

wheel

cylinders
are

corroded
or

damaged

Bleed
screw
is

open

Pedal

linkage
is

binding
or

push
rod

adjust

ment
is
too

long

Master

cylinder
compensator
part
is
ob

structed

Seized
master

cylinder
piston

Poor
shoe
condition

Poor

wheel
cylinder
condition

Deformation
of

piston
cups

Hand
brake
will
not
return

Clogged
master

cylinder
return

port

Improper
tire
inflation

Improper
adjustment
of
shoe

to
drum
clear

anee

Grease
oil
mud
or
water
on

linings
or

pads

Mud
in

brake
drum

Deterioration
of

linings
or

pads

Excessive
wear
of

linings
or

pads

BR
23
Corrective
action

Grind
or

replace
as

required

Tighten

support
plate
bolts
to

specified

torque
or

replace
plate

Replace
as

necessary

Replace
linings

Blowout

assembly
with

compressed
air
or

refinish
drum

Replace
faulty
unit

Replace
if

faulty

Cam

ground
lining
to
eliminate

glaze
If

it

doesn
t

replace
linings

Turn

drum
or

replace
as
necessary

Drain
and
fill

system
with

approved
fluid

Replace
linings

Repair
or

replace
as
necessary

Repair
as
necessary

Close
screw
and
bleed

system

Lubricate

linkage
check

pedal
return

spring

for
condition
and

adjust
push
rod

as
neces

sary

Blowout

foreign
matter
with

compressed

air

Disassemble
master

cylinder
and

replace

piston
Bleed

system

Clean
and

repair

Repair
or

replace

Replace

Check
and

repair

Clean

Inflate
to
correct

pressure

Readjust

Clean
brake

mechanism
and
check
for
cause

of

problem
Replace
linings
or

pads

Clean

Replace

Replace

Page 402 of 537


DESCRIPTION

MAINTENANCE
AND
SERVICE

TIRE
INFLATION

TIRE
REPAIR

WHEEL
REPAIR

WEAR

DESCRIPTION

The

620
series
models
are

equipped

with

4lV
14

wheels
with
25

mOl
0
98

in

offset
All
tires

are
tubeless
Wheel

and
Tire

WHEEL
AND

TIRE

CONTENTS

WT2

WT
2

WT2

WT2

WT
2

WT
2
TIRE

ROTATION

CHANGING
TIRE

INSPECTION

WHEEL

BALANCE

WHEEL
AND

TIRE

Tire
size

Model
Tire
size
Wheel
size

All

models
6

00
I
4
6PR

Tubeless
4UJ
14

Tire

pressure

Unit

kgl
em
2

psi

Vehicle

speed
km
h

MPH
Under

Over

100
km
h
100
km
h

Model

60

MPH
60
MPH

Front

1
5
21
1
8

26

Unloaded

Rear
175

25
2
25
32

All

models

Front

1
5

21
1

8
26

Loaded

Rear
3
0

42
3
15
4S

Note
Tire
inflation

pressures
should

be
measured

when
tires
are
cold

MAINTENANCE
AND

SERVICE

TIRE

INFLATION

Correct
tire

pressure
is

very
im

portant
to
ease
of

steering
and

riding

comfort

This
also
reduces

driving

sound

to
a
minimum

resulting
in

longer
tire

life
that
is

overinflation
or
underinflation

promotes
wear
at

cen

ter
tread
or

shouider
of
tire

If

aU
tires
are

inspected
frequently

and
maintained

correct
tire

pressure
it

is

possible
to

detect

sharp
material

in

the
tread

Also
the
above
check

avoids

abnormal
wear
which
invites
serious

problem
If
tires
indicate

abnormal
or

uneven

wear
the
cause
of

problem

should
be
detected
and
eliminated

After

inflating
tires

leakage
in
valve

should
be

checked
Without

valve

caps

leakage
will

occur
due
to

dirt
and

water

resulting
in

underinflation
Ac

cordingly
whenever
tire

pressure
is

checked
be
sure
to

tighten
valve

caps

firmly
by
hand

WT
2
WT3

WT3

WTA

WTA

WT
4

TIRE
REPAIR

In
order

to

inspect
a
leak

apply

soapy
solution
to
tire
or

submerge
tire

and
wheei

in
the

water
after

inflating

tire
to

specified

pressure
Special
in

spection
for

leaks
should
be
carried

out
around
the
valve
wheel
rim
and

along
the
tread

Exercise
care
to
bead

and
rim
where

leakage
occurs

Wipe

out
water
from

area
which

leaks
air

bubbles
and

then
mark
the

place
with

chalk

After

removing
the
materials
which

caused

puncture
seal
the

point
When

repairing
the

puncture
use
the

tire

repair
kits

which
are
furnished
from

tire
dealers

following
the
instructions

provided
with
the

kits
In

case
that
a

puncture
becomes

large
or
there
is

any

other

damage
on
the

tire
fabric

repair

must
be

carried
out

by
authorized

tire

dealers

WHEEL
REPAIR

Inspect
the
wheel
rim

flange
for

bend

or
dents

The

flange
should
be
cleaned

by
a

wire

brush
when
rust
is
found

on
the

flange
Furthermore
if
excessive

pitting
occurs

on
the

rim
eliminate
it

with
a
file

WEAR

Missilgnment

When
the
front
wheels

align
in

excessive
toe
in
or

toe
out
condition

tires

scrape
the

tread
rubber
off
The

wear
of
tread

appears
feathered

edge

Page 403 of 537


Center

This

wear
is
caused

by
overinflation

of
the
tire
The
inflation

pressure
must

be

kept
at
the

specified
value

Shoulder

The
wear

may
be
caused

by
under

inflation
incorrect
wheel
camber
or

continuous
high

speed
driving
on

curves
In

general
the
former
two

causes
are
common
Underinflation

wear
occurs
on

both
sides
of

treads

d
I

Ii

Toe
in
or

toe
out
wear

nf
I

Underinnation
wear

TIRE
ROTATION

Tires
wear

unevenly
and
become

unbalanced

according
to

running
dis

tance
Uneven
tire
wear
often
results

in
tire
noise

which
is
attributed
to
rear

axle

gears
bearing
etc
Meanwhile
the

front
tires
tend
to
wear

unevenly

because
of

improperly
aligned
front

wheel

Accordingly
to

equalize
tire
wear

it
is

necessary
to

rotate
tires

peri

odically

All
the
tires

including
the

spare
tire

are
of
the

same

type

Right
front

Right
rear

14
1

I

@
Spare

t
t
1

1

Left

front
Left
rear

Fig
WT
2
Tire
rotation
1
Wheel
and
Tire

and

on
the
other
hand
camber
causes

wear

only
on

one
side
of
treads
For

cornering
tread
wear
the

driver
must

operate
vehicle

slowing
down
on

curves

Uneven

Uneven
wear
is
caused

by
incorrect

camber
or
caster

malfunctioning
sus

pension
unbalanced
wheel
out
of

round

brake
drum
or
other
mechani

cal
conditions
To

repair
this
abnormal

wear

correct
the

above

faulty
parts

J

I

II

i

11
I

1

Overinllation
wear

1

I
I

t

Uneven
wear
WT007

Fig
WT
1
A
bnormal
tire
wear

The

spare
lire
has

a
different
brand

from
4
tires
on

the
vehicle

Right
front

Right
rear

I

@
Spare

x

J
r

Left
front
Left
rear

The

pare
tire
should
be
used

in
an

emergency
only

Fig
WT
3
Tire
rotation
2

The
tires
are

provided
with
tread

wear

indicator
at
six

places
around

tire
circumference
indicating
1

6
mm

J
in
tread

depth
When
the
tires

wear
and
then
the
marks

appear
re

place
them
with

new
ones
See

Figure

WT

4

WT3
Tire
tread

0E
I
Tread

wear
indicator

c

WH024

Fig
WT
4
Tread
wear
indicator

CHANGING
TIRE

To

change
tire
with
wheel

using
a

jack
in
the
safe
manner
observe
the

following
procedures

1
To

remove

spare
tire
insert

jack

rod

to

guide
and
then
turn
it
counter

clockwise
When

installing
lighten
a

little

strong
after

lifting
up
and
lock

Fig
WT
5
Removing
spare
tire

2
It
is

necessary
to
remove
wheel

cap
and
temporarily
to
loosen

wheel

nuts
before
vehicle
is

jacked
up

3
To

jack
up
front

place

jack
under

side

frame
about
S20

mOl
20
5
in
at

rear
of
front
axle

center
after

apply

ing
parking
brake
and

blocking
rear

wheels

g
1

WT012

Fig
WT
6

Jacking
up
front
side

Page 414 of 537


STEERING
SYSTEM

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Steering
wheel
moves

heavily

Steering
wheel
turns

but

sluggishly

Vehicle

pulls
to
one

side
Probable
cause

Wheel

alignment
out
of

specifications
or
air

pressure
in
tires

too
low

Steering

linkage
out
of

adjustment

Steering
column
out
of

alignment

Wheels
out
of

alignment
or
air

pressure
in

tires

too
low

Damaged
steering
linkage

Wheels
out

of

proper
alignment

Wheel

bearing
out
of

adjustment

Damaged

steering
linkage

ST
9
Corrective
action

Align
or

inflate
tires

to
correct

pressure

Adjust
and

see
relative

topic
under
Front

Suspension

Repair

Repair
or
inflate
tires

to
correct
air

pressure

Replace
and
see
relative

topic
under
Front

Suspension

Align

Adjust

Replace
and

see
relative

topic
under
Front

Suspension

Page 451 of 537


To

adjust
vertical
aim

use

adjusting

screw

on

upper
side

of

headlamp
and

to

adjust
horizontal
aim

use

adjusting

screw

on
side

of
head

lamp

Notes

Before

making
headlarnp
aiming
ad

justment
observe
the

foUowing
in

structions
Body
Electrical

System

a

Keep
aU

tires
inflated
to
correct

pressures

b
Place

vehicle
and
tester

on
the

same

flat
surface

c

See
that
there

is
no
load
in
vehicle

I
Gasoline
radiator
and

engine
oil

pan
filled

up
to

correct
levels

2
Without

passenger
When

performing
headlamp
aiming

adjustment
use
an

aiming
device

aiming
wall
screen
or

headlamp
tester

For

operating
instructions
of

any

aimer

refer
to

respective
operation

manuals

supplied
with
the
unit

DRIVING
BEAM
HIGH

BEAM

L

wt

H
G

hi
i

iiI

PASSING
BEAM
LOW
BEAM
10
m
32
8
ft

W2

H2
10
m

02
8
n

d

20

h2
I

02

I

I

f
10
m

32
8
ft

Driving
beam

High
beam

Passing
beam
Low

beam

HI

WI
01

mm
mm

CO

in
in

I
715
780

48

All
models

28
15
30

71
hI

H2
W2

h2

O2
d

mm
mm
mm

in

in
in
0

140

I
715

11
160

12018
5
51
28

15
45

67
mm
mm

in
in

392
349

is
43
13
74

BE302

Fig
BE
8

Aiming
adjustment

BE

6