1977 DATSUN PICK-UP air condition

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

3
If
there

is
a
leak

remove

top

cover
from

purge
contiol
valve
and

check

for
dislocated
or

cmcked
dia

phragm
If

necessary
replace
dia

phmgm
kit

which
is
made

up
of
a

retainer

diaphragm
and

spring

I
@

1
Cover

2

Diaphragm

3
Retainer

4

Diaphragm
spring

Fig
ET
47
ET350

Carbon
caniater

purge

control
valve

Carbon
unlster

filter

Check
for
a
contaminated

element

Element
can
be
removed
at

the

bottom
of
canister

installed
on
vehicle

body

Fig
ET
48

Replacing
carbon

canister

filter

Fuel
tank

vacuum
relief

valve

operation

Remove
fuel
filler

cap
and
see
it

functions

properly

I

Wipe
clean
valve

housing
and
have

it
in

your
mouth

2

Inhale
air
A

slight
resistance

ac

companied
by
valve
indicates
that

valve
is
in

good
mechanical
condition

Note
also
that

by
further

inhaling
air

the
resistance
should
be

disappeared

with
valve
clicks
Engine
Tune

up

3
If
valve

is

clogged
or
if
no
resist

ance
is

felt

replace
cap
as
an
assem

bled
unit

r

u

ET369

Fig
ET
49
Fuel

filler
cap

CHECKING

CATALYTIC

CONVERTER

INSPECTION

Preliminary
inspection

Visually
check
condition
of
all

component
parts
including
hoses

tubes
and
wires

replace
if

necessary

Refer
to

Inspection
of
A
I

S
on

page
EC
17

Catalytic
converter

Whether

catalytic
converter
is
nOf

mal
or
not
can
be
checked

by
ob

serving
variation
in
CO

percentage

The

checking
procedure
is

as
follows

Apply
parking
brake
Shift

gears

into

Neutral
for
manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1

Visually
check

catalytic
converter

for

damage
or
cracks

2
Remove
air

hose
between
5

way

connector
and
air

check
valve

Plug
the

disconnected
hose
to

prevent
dust

from

entering
Refer
to

page
ET
12

3
Check
carburetor

pipes
for

proper

connection

4

Warm

up
engine
sufficiently

5
Race

engine
1
500
to
2
000

rpm

two

or
three
times
under
no
load
then

run

engine
for

one
minute
at

idling

speed

6

Adjust
throttle

adjusting
screw

until

engine
attains
to

specified
speed

Refer
to

page
ET
12

7

Check

ignition
timing
If

neces

sary

adjust
it
to

specifications
Refer

to

page
ET
10

ET
23
8

Adjust
idle

adjusting
screw
until

specified
CO

percentage
is

obtained

Refer
to

page
ET
12

9

Repeat
the

adjustment
process
as

described
in

steps
5
to

8
above
until

specified
CO

percentage
is

obtained

Note

Adjustment
in

step
9
should
be

made
ten
minutes
after

engine
has

warmed

up

10
Race

engine
1
500
to
2
000

rpm
two
or
three
times
under

no
load

and
make

sure
that

specified
CO

per

centage
is
obtained

I
1
Remove

cap
and
connect
air

hose
to
air
check
valve

If

idling

speed
increases

readjust
it

to

specified
speed
with
throttle
ad

justing
screw

12
Warm

up
engine
for
about
four

minutes
at
2
000

rpm
under
n
load

13
Measure

CO

percentage
at

idling

speed
After

step
12
has
been
com

pleted
wait

for
one
minute
before

making
CO

percentage
measurement

14

If
CO

percentage
measured
in

step
13
is
less
than
0
3
the

catalylic

converter
is

normal

15
If
CO

percentage
measured
in

step
13
is

over
0
3
recheck
A
I
S

and

replace
air

check
valve
Then

perform
inspection
steps
12

and
13

16
If
CO

percentage
is
still

over

0
3
in

step
15

catalytic
converter
is

malfunctioning
Replace
catalytic
con

verter

CHECKING
FLOOR

TEMPERATURE

WARNING
SYSTEM

INSPECTION

Floor

warning
temperature

system

Apply
parldng
brake
Shift

gears

into
Neutral
for

manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1

Ensure
that
floor
tern

perature

warning

lamp
lights
when

ignition

switch
is

turned
to
the
S

position

If
not
check

lamp
for
burned

bul
bs

Engine
Tune

up

TROUBLE
DIAGNOSES
AND

CORRECTIONS

Condition
Probable
cause

CANNOT
CRANK

ENGINE
OR

SLOW

CRANKING
Improper
grade
oil

Discharged
battery

Faulty
battery

Loose

fan
belt

Malfunction
in

charge
system

Wiring
connection
loose
in

starting
circuit

Faulty
ignition
switch

Faulty
starler
motor

Trouble

shooting
procedure
on

starting
circuit

Switch
on
the

starting
motor
with

light
ON

When

light
goes
off
or
dims

considerably

a
Check

battery

b
Check
connection
and

cable

c
Check
starter
motor

When

light
stays
bright
Corrective
action

Replace
with

proper
grade
oiL

Charge

battery

Replace

Adjust

Inspect

Correct

Repair
or

replace

Repair
or

replace

a
Check

wiring
connection
between

battery
and
starter

motor

b
Check

ignition
switch

c
Check
starter
motor

ENGINE
WILL
CRANK

NORMALLY
BUT

WILL
NOT

START

In
this
case
the

following
trouble
causes

may
exist

but
in

many
cases

ignition

system
or
fuel

system
is
in

trouble

Ignition

system
in
trouble

Fuel

system
in
troubk

Valve
mechanism
does
not
work

properly

Low

compussion

Trouble

shooting
procedure

Check

spark
plug
firstly
by

following
procedure

Disconnect

high
tension
cable
from
one

spark
plug
and
hold
it

about
10
mm
0
39
in

from
the

engine
metal

part
and
crank

the

engine

Good

spark
occurs

Check

spark
plug

b
Check

ignition
timing

c
Check
fuel

system

d
Check

cylinder
compression

Check
the
current
f10
in

primary
circuit

Very
high
current

Inspect
primary
circuit
for
short

Check
breaker

poiIit
operation

except
tran

sistor

ignition
system
No

spark
occurs

ET

27

Engine
Tune

up

Condition

Probable

cause

Low
or
no

current

Ign
tion

system
out
of

order
Burned
distributor

point

Improper
point

gap

Faulty
condenser

Leak
at
rotor

cap
and

rotor

Faulty

spark

plug

Improper
ignition
timing

Faulty
ignition
coil

Disconnection

of

high
tension

cable

Loose
connection
or
disconnection
in

primary
circuit

Fuel

system
out
of

order
Lack
offuel

Dirty
fuel
strainer

Dirty
or

clogged
fuel

pipe

Fuel

pump
will
not
work

properly

Carburetor

choke
will
not
work

properly

Improper

adjustment
of
float
level

Improper
idling

Dirty
or

clogged
carburetor

Clogged
breather

pip
of
fuel
tank

Malfunctioning
an
ti

dieseling
solenoid
valve

Incorrect
sparle

plug
tightening
or

faulty

gasket

Improper
grade
engine
oil
or
low

viscosity

Incorrect
valve
clearance

Compression
leak
from
valve

seat

Sticky
valve

stem

Weak
or

damaged
valve

springs

Compression
leak
at

cylinder
head

gasket

Sticking
or

damaged
piston
ring

Worn

piston

ring
or

cylinder

Trouble
ooting

procedure

Pour

the

engine
oil
from

plug
hole
and
then

measure

cylinder

compression

Compression
increases

Compression
does

not

change
Low

comp
ion

ET
28
Corrective
action

Check
for
loose

terminal
or
disconnection

in

primary
circuit

Check
for

burned

points

Repair
or

replace

Adjust

Replace

Clean

or

replace

aean

adjust
plug
gap
or

replace

Adjust

Replace

Replace

Repair
or

replace

Supply

Replace

Clean

Repair
or

replace

Check
and

adjust

Correct

Adjust

Disassemble

and
clean

Repair
and
clean

Check
for

loose
terminal
or
wire
harness

Tighten
to
normal

torque
or

replace
gasket

Replace
with

proper
grade
oil

Adjust

Remove

cyljnder
head

and

lap
valves

Correct
or

replace
valve

and
valve

guide

Replace
valve

springs

Replace

gasket

Replace
piston
rings

Overhaul

engine

Malfunctiong

cylinder
or
piston
ring

Compression
leaks
from
valve

cylinder
head

or
head

gasket

Except
transistor

ignition
system

Condition

IMPROPER
ENGINE

IDLING

Fuel

system
out
of

order

Low

compression

Others

High
engine
idle

speed
Engine
Tune

up

Probable
cause

Clogged
or

damaged
carburetor

jets

Incorrect
idle

adjustment

Clogged
air
cleaner
filter

Damaged
manifold

gaskets
or
carburetor

insulator

Improper
float
level

adjustment

Loose
air

hoses
or
air

fuel
mixture
hoses
of

carburetor

Malfunctioning
carburetor
choke

Malfunctioning
anti

backfire
valve

Malfunctioning
automatic

temperature
con

trol
air

cleaner

Inoperative
idle

compensator

Carbon
canister

purge
line
hose

damaged
or

disconnected

Stick
E

F
E
valve
shaft

Incorrect
valve
clearance

Extremely
low
revolution

Faulty
malfunction
of
the

ignition
system

spark
plug

high
tension
cable
breaker

point
ignition
coil
etc

Incorrect
basic

ignition
timing

Malfunction
of
choke
valve
or

linkage

Malfunction
of
vacuum
motor
sensor
or

hoses
of
air
cleaner

Incorrect
idle

adjustment

Clogged
air
cleaner
fdter

Malfunction
of
idle

compensator
of

air

cleaner

Malfunction
of
E
G
R
control
valve

Loose
manifold
and

cylinder
head
bolts

Dragged
accelerator

linkage

Incorrect
idle

adjustment

Malfunction
of
B
CDD

system

Malfunction
of

speed
switch
and
harness

ET
29
Corrective
action

Clean
or

replace

Adjust

Replace
element

Replace
gasket
or
insulator

Adjust

Check
for
loose
connections

Check
and

adjust

Check
for
loose
connection
of
vacuum
hose

Check
A

r
C
air
cleaner

Check
for
connection
of
idle

compensator

hose

or
replace
idle

compen
tor

Connect
or

replace

Repair

Previously
mentioned

Adjust

Adjust

Replace

Adjust

Adjust

Check
for
loose
hoses

Replace
system
com

ponents
if
necessary

Adjust
idle

speed

Replace
air
cleaner
fdter

Replace

Clean
or

replace

Retighten
bolts

Check
and

correct
accelerator

linkage

Adjust
idle

speed

Check
for
loose

vacuum
hose
and
harness

connections

Adjust
or

replace
if

necessary

Check
for
loose
connections

Repair
or

replace
if

necessary

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

Condition

NOISY

ENGINE

Car

knocking

Mechanical

knocking

Crankshaft

bearing

Imocking

Connecting
rod

bearing
knocking

Piston
and

cylinder

noise

Piston

pin
noise

Water

pump
noise

Air

pump
noise

Others
Engine
Tune

up

Probable
cause

Overloaded

engine

Carbon

knocking

Timing
knocking

Fuel

knocking

Preignition
misusing
of

spark
plug

This

strong
dull
noise
increases
when

engine

is

accelerated
To
locate
the

place
cause
a

misfire

on
each

cylinder
If
the
noise

stops

by
the
misfire
this

cylinder
generates
the

noise

This
is
a
little

higher
pitched
noise
than
the

crankshaft

Imocking
and
also
increases

when

engine
is
accelerated
Cause
a
misfire

on
each

cylinder
and
if
the
noise
deminishes

almost

completely
this
crankshaft

bearing

generates
the
noise

When

you
hear
an

overlapping
metalic
noise

which
increases
its

magnitude
with
the

revolution
of

engine
and
which
decreases
as

engine
is
warmed

up
this
noise
is
caused

by

piston
and
cylinder
To
locate
the

place

cause
a
misfire
on
each

cylinder

This
noise
is

heared
at
each

highest
and

lowest
dead
end
of

piston
To
locate

the

place
cause
a

misfire
on
each

cylinder

This
noise

may
be
caused

by
worn
or

damaged
earings
or
by
the
uneven
surface

of
sliding

parts

Damaged
air

pump

An
improper
adjustment
of
valve
clearance

Noise
of

timing
chain

An
excessive
end

play
on
crankshaft

Noisy
E
F
E

valve
shaft

Wear
on
clutch

pilot
bushing

Note
This
noise
will
be
heared
when

clutch
is

disengaged

ET31
Corrective
action

Use

right
gear
in
driving

Disassemble

cylinder
head
and

remove

carbon

Adjust
ignition
timing

Use

specified
octane
fuel

Use

specified
spark
plug

This
is

caused

by
worn
or

damaged
bearings

or
unevenly
worn
crankshaft
Renew

bearings
and

adjust
or

change
crankshaft

Check
lubrication

system

Same
as
the
case
of
crankshaft

bearings

This

may
cause
an
abnormal

wearing
of

cylinder
and
lower

compression
which
in

turn
will
cause
a
lower
out

put
power
and

excessive

consumption
of
oil

Overhaul

engine

This

may
cause
a
wear
on

piston
pin
or

piston
pin
hole

Renew

piston
and

piston

pin
assembly

Replace
water

pump
with
a
new
one

Repair
or

replace

Adjust

Adjust
the
tension
of
chain

Disassemble

engine
and
renew
main
bearing

Repair

Renew
bush

and

adjust
drive
shaft

Condition

ABNORMAL

COMBUSTION

backfue
afterflre

run
on
etc

Improper

ignition
timing

Fuel

system
out
of

order

Faulty
cylinder
head
etc

Others

EXCESSIVE
OIL

CONSUMPTION

Oilloak

Excessi
lo
oil

consumption

Others
Engine
Tune

up

probable
cause

Improper
ignition
timing

Improper
heat

range
of

spark
plugs

Damaged
carburetor

or
manifold

gasket

backfue
afterfire

Clol
l
ed
carburetor

jet

Improper
function
of

the
float

Uneven

idling
Run
on

Improperly
adjusted
B

C
D
D

set

pressure

Malfunction
of
anti

dieseling
solenoid
valve

Malfunction
of
auio
choke

Improperly
adjusted
valve
clearance

Excess
carbon
in

combustion
chamber

Damaged
valve

spring
backfire
afterflre

Malfunction
of

A
T
C

air
cleaner

Inoperative
ariti
backfue
valve

Loose
oil
drain

plug

Loose

or
damaged
oil

pan
gasket

Loose
or

damaged
chain
cover

gasket

Worn
oil
seal
in
front
and
rear
of
crankshaft

Loose
or

damaged
locker
cover

gasket

Improper
tightening
of
oil
filter

Loose
or

damaged
oil

pressure
switch

Cylinder
and

pioton
wear

Improper
location
of

piston
ring

gap
or

reversely
assembled

piston
ring

Damage
piston
rings

Worn

piston
ring
groove
and

ring

Fatigue
of
valve
oil
seal

lip

Worn
valve

stem

Inadequate
quality
of

engine
oil

Engine
overheat

ET32
Corrective
action

Adjust
ignition
timing

Use

specified
spark
plugs

Replace
them
with
new

parts

Disassemble
carburetor
and
check
it

Adjust
the
level
and
check
needle
valve

Adjust

Adjust

Check
or

replace

Adjust

Adjust

Remove
head
and

get
rid
of
carbon

Replace
it
with
a
new
one

Check
for
loose
vacuum
hoses

Replace
if

necessary

Replape

Tighten
it

Renew

gasket
or

tighten
it

Renew

gasket
or

tighten
it

Renew
oil
seal

Renew

gasket
or

tighten
it
but
not
too

much

Renew

gasket
and

tighten
it
with
the

proper

torque

Renew
oil

pressure
switch
or

tighten
it

Overhaul

cylinder
and
renew

piston

Remoun
t

piston
rings

Renew

rings

Repair
or
renew

piston
and

cylinder

Renew

piston
and

piston
ring

Replace
seal

lip
with
a

new
one

Renew
valve
or

guide

Use
the

designated
oil

Previously
mentioned