engine overheat 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 44 of 537


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

Page 45 of 537


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

Page 77 of 537


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

Page 96 of 537


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

Page 145 of 537


Minimizes
exhaust

gas
tempera

lure
rise

2
Minimizes

horsepower
losses
re

suiting
from
air

injection
into
the

exhaust

system

3
Protects

pump
from
excessive

back

pressure

The
air

pump
relief
valve
is
installed

as
shown
in

Figure
EC

20

The

secondary
air
is

discharged

from
the
air

pump
relief
valve

to
the

dust
side
of
the
carburetor
air
cleaner

To
carburetor

air
cleaner

Secondary

air

To
carburetor

air

cleaner

J
erCOndary

r

r

EC294

Fig
EC
20
Air

pump
relief
valve
Emission
Control

System

Emargency
air
retial
valve

E
A
R
Valve

California
models

The

emergency
air
relief
valve
con

trols
the

quantity
of
secondary
air

fed

from
the
air

pump
according
to

load

condition
and
it

discharges
the
see

ondary
air
into
the

atmosphere
to

prevent
overheating
of
the

catalytic

converter

The

emergency
air
relief
valve
con

sists
of
a

diaphragm
a

spring
and

a

valve
which
is

coupled
to

diaphragm

1

Diaphragm

2

Val

3

Spring

4

Diaphragm
chamber

EC536

Fig
EC

21

mergency
air

relief
valve

OPERATION

As
mentioned

previously
there

are

two

types
of
Air

Injection
Systems

A
I

S
a

non
California

type
and
a
California

type
The
California
stand

ard

type
includes
a

system
which

controls

injection
of

secondary
air

so

as
to
assure

proper
function
of
the

catalytic
converter
and
a

system

which
controls
the

supply
of
second

ary
air
to

prevent
abnormal

tempera

tUfe
rise
in
the

catalytic
converter

The
A
I
S
consists
of
the

following

systems

L
A

system
which
allows

injection

of

secondary
air
into
the
exhaust

port

2
A

system
which

bypasses
sec

ondary
air

from
the
air

pump
relief

valve

to
the

carburetor
air

cleaner

during

high
speed
engine
operation

3
A

system
which

supplies
air

from

the
carburetor
air
cleaner

to
the
intake

manifold

by
means
of
the
anti

backfire

valve
so
as
to

prevent
after
fire

during

deceleration

4
A

system
which

controls

injection

of
the

secondary
air

by
means
of
the

air

control
valve

so
as
to
maintain
the

catalytic
converter
at
an

optimum

temperature
level
under

lightly
loaded

condi
tions

Califomia

type
only

5
A

system
which
controls
the

sup

ply
of

secondary
air

through
the
emer

gency
air

relief
vilve

io
pfevent
ab

normal

temperature
rise
of
the

cataly

tic

converter

California

type
only

A
I

S

operation
is

as
follows

I

I

t

1
r

9

I
Air

pump
6

Check
valve

I
0
L
2
Air

pump
air
deaner
7
Air

gallery
pipe

3
Air

relief
valve
8
Injection
non
e

r
4
Air
cleaner
9

Exhaust
manifold

5

Carburetor
10

Anti
backflIe
valve

EC179

Fig
EC
22
Non

California
type
A
I
S

EC
12

Page 214 of 537


DESCRIPTION

INSPECTION

CLEANING
AND
REGAP

DESCRIPTION

The

spark
plugs
are
of
the

conven

tional

type
having
14
mm
0

551
in

threads
The

spark
plug
gaps
are
1
0
to

1
1
mm
0
039
to
0
043
in
on
Cali

fomia
models
and
0
8

to
0
9
mm

0
031
to

0
035
in
on
non
California

models
The

inspection
and

cleaning

should
be
made
every
suitable
mainte

nance

period
If
necessary
replace

Note
All

spark

plugs
installed
on
an

engine
must
be

of
the
same
brand

and
the

same
number
of
heat

range

INSPECTION

L
Remove

spark
plug
wire

by

pulling
on

boot
not
on
wire
itself

2
Remove

spark
plugs

3

Check
electrodes
and
inner

and

outer

porcelains
of

plugs
noting
the

type
of

deposits
and
the

degree
of

electrode
erosion

Refer
to

Figure

EE
96

Normal
Brown
to

grayish
tan
de

posits
and

slight
electrode
wear

indicate
correct

spark
plug
heat

range

Carbon
fouled

Dry
fluffy
carbon

deposits
on
the
insulator
and

electrode
are

usually
caused

by

slow
speed
driving
in

city
weak

ignition
too
rich
fuel
mixture

dirty
air
cleaner
etc

It
is

advisable
to

replace
with

plugs

having
hotter
heat

range

Oil
fouled
Wet
black

deposits
indi

cate
excessive
oil
entrance
into

combustion
chamber

through
worn

rings
and

pistons
or
excessive
clear

ance
between
valve

guides
and

stems
If
the
same
condition
re

mains
after

repair
use
a
hotter

plug
Engine
Electrical

System

SPARK
PLUG

CONTENTS

EE
4B

EE
47

EE
47

EE
47
SERVICE
DATA
AND
SPECIFICATIONS

TROUBLE
DIAGNOSES
AND

CORRECTIONS
EE
4B

Overheating
White
or

light

gray
in

sulator
with
black
or

gray
brown

spots
and
bluish
burnt
electrodes

indicate

engine
overheating
More

over
the

appearance
results
from

incorrect

ignition
timing
loose

Normal

Overheating

EE079

4
After
cleaning
dress
electrodes

with
a
smaU
fine
file
to
flatten
the

surfaces
of
both
center
and
side

electwdes
in

parallel
Set

spark
plug

gap
to

specification

5
InstaU

spark
plugs
and

torque

each

plug
to
L5

to
2
0

kg
m

11
to
14

ft
Ib

6
Connect

spark

plug
wires

CLEANING

AND
REGAP

Clean

spark
plugs
in

a
sand
blast

type
cleaner
Avoid
excessive

blasting

Clean
and
remove
carbon
or
oxide

deposits
but
do
not

wear
away

porcelain
If

deposits
are
too
stubborn

EE
47
spark
plugs
low
fuel

pump
pres

sure

wrong
selection
of
fuel
a

hotter

plug
etc

It
is
advisable
to

replace
with

plugs

having
colder
heat

range

Ir

i

Carbon
fould

Worn

Fig
EE
96

Spark
plug

discard

plugs

After

cleaning
spark
plugs
renew

firing
surface
of
electrodes
with
me

mentioned
aboVe
Then

gap
spark

plugs
to

specified
values
with
a
round

wire
feeler

gauge
All

spark
plugs
new

or
used
should
have
the

gap
checked

and
reset

by
bending
ground
electrode

EEOBO

Fig
EE
97

Setting
park
plug
gap

Page 231 of 537


CLUTCH

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Probable
cause
and

testing

Clutch

slips
Corrective
action

Slipping
of
the

clutch

may
be

noticeable
when

any
of
the

following
symptoms
is

encountered

during
operation

I
Vehicle
will

not

respond
to

engine

speed
during
acceleration

2
Insufficient
vehicle

speed

3
Lack
of

power
during
uphill
driving

Some
of
the

above
conditions
are
also

experienced
when

engine

problem
is

oc

urring
First

de
tennine
whether

engine
or
clutch
is

causing
the

problem

If

slipping
clutch
is

left
unheeded
wear
and
or

overheating
will
occur
on
clutch

facing
until
it
is

no

longer
serviceable

TO
TEST
FOR
SLIPPING
CLlJfCH

proceed
as
follows

During
upgrade
travelling
run

engine
at

about
40
to
50
km

h
25
to
31

MPH
with

gear
shift

lever
in

3rd

speed
position
shift
into

highest
gear
and
at
the
same
time

rev

up
engine
If
clutch

is

slipping
vehicle
will
not

readily

respond
to

depression
of
accelerator

pedal

Clutch

facing
worn

excessively

Oil
or

grease
on
clutch

facing

W

r
d
clut
h
cov
r

pressure
plat
Replace

Replace

tpa
o
e
lace

Dragging
clutch
is

particularly
noticeable
when

shifting
gears
especially
into

low

gear

TO
TEST
FOR
DRAGGING
CLlJfCH

proceed
as
follows

I
Start

engine
Disengage
clutch
Shift
into

reverse

gear
and
then
into
Neutral

Gradually

increase

engine
speed
and

again
shift
into
reverse

gear
If
clutch
is

dragging
gear
grating

is

heard
when

shifting
from
Neutral
into

Reverse
Clutch

drags

2

Stop
engine
and
shift

gear
Conduct
this
test
at
each

gear
position

3
Gears

are
smoothly
shifted
in

step
2
but

drag
when

shifting
to
1st

speed
position
at

idling

a
If

dragging
is
encountered
at
the
end
of

shifting
check
condition
of

synchro

mechanism
in
transmission

b
If

dragging
is
encountered
at
the

beginning
of

shifting
proceed
to

step
4

below

4
Push

change
lever
toward
Reverse
side

depress
pedal
to
check
for
free
travel

a

If

pedal
can
be

depressed
further
check
clutch
condition

b
If

pedal
cannot
be

depressed
further

proceed
to

step
5
below

5
Check
clutch
control

pedal
height
pedal
free
travel
withdrawal
lever

play
etc

If
no
abnonnal

condition
exists
and
if

pedal
cannot
be

depressed
further
check
clutch

condition

Clutch
disc
runout
or

warped

Wear

or
rust

on
hub

splines
in
clutch
disc

Diaphragm
spring
toe

height
out
of
ad

justment
or
toe

tip
worn

Worn
or

improperly
installed

parts

CL10
Repair
or

replace

Clean
and
lubricate
with

grease
or

replace

Adjust
or

replace

Repair
or

replace

Page 320 of 537


Trouble

No
shock
at

change
from
I

to
2

range
or

engine
races

extremely

Failure
to

change
from
3rd
to
2nd

when
shifting
lever
into
I

range

Engine
brake
does
not

upcrate
in

1

range

Gear

change
frum
I

sr
lu

2nd

or
from
2nd
to
3rd
in
I

range

Does
not

change
f

rom

2nd

to
1st
in

range

Large
shock

changing
from
2nd

to
1st
in

range

Vehicle
moves
when

changing

into

P

range
or

parking
gear
does

not

disengage
when
shifted

out
of

P

range

Transmissic
m

overheats

Oil
shoots
out

during
operation

White
smoke
emitted
from
exhaust

pipe

during
operation

Offensive

smell
at
oil

charging
pipe

Transmission

noise
in
p
and
N

ranges

Transmission
noise
in

D
2
I

and
R

ranges
Automatic

Transmission

ABeD
E

F
G
H
I
J
K
L

1M
NO
P

1m
n

q
r
s
t

u
v

Iw
x

y

6
7
5

@
@
I

I
2
3
4
I

I

2
1

57
6

3

@@

@

I

2
4

5
3

@
f

1
2

@

1
2
4567
3

@
2

1
3

@
2
4

I

2

I

3
4

2
6
8
7
5

@@@

Q
@@
@

I
3

5
6
2
7

8
4

@@@
Q
@@

@

1

2

O
G
@@
f
@@

@

1
2

10
I

I

2

0
G
@
@

AT
56

Page 321 of 537


Automatic
Transmission

TROUBLE
SHOOTING
GUIDE
FOR
3N71B
AUTOMATIC

TRANSMISSION

Order
Test
item

Checking
Oil
level

gauge

2
Downshift
solenoid

3

Manuallinkage

L

4
Inhibitor
switch

5

Engine
idling
rpm

6
Vacuum

pressure
of

vacuum

pipe

7

Operation
in
each

range

8

Creep
of
vehicle

Stall
test
I

Oil

pressure
before

tesling
1

2
Stall
test

3
Oil

pressure
after

testing

Road
test
Slow
acceleration

I

st
2nd

2nd
3rd

2

Quick
acceleration

lst
2nd

2nd
3rd

3

Kick
down

operation

3rd
2nd

or

2nd
1st
Procedure

Check

gauge
for
oil
level
and

leakage
before
and

after
each

test

Check
for
sound
of

operating
solenoid
when

depressing

accelerator

pedal
fully
with

ignition
key
ON

Check

by

shifting
into

P
lR
IN
D
2
and
I

ranges
with
selector
lever

Check

whether
starter

operates
in
N
and
p

ranges
only

and
whether
reverse

lamp
operates
in

R
range
only

Check
whelher

idling
rpm
meet

standard

Check
whether

vacuum

pressure
is

more
than
450

mmHg

in

idling
and
whether
it

decreases
with

increasing
rpm

Check
whether
transmission

engages
positively
by
shifting

N
0
N

2
N

l
I
and
N
R

range

while

idling
with
brake

applied

Check
whether

there
is

any
creep
in
D
2

R

ranges
and

Measure
line

pressures
in
D
2
I
and
R

range
while

idling

Measure

engine

rpm
and
line

pressure
in
D
2
I

and

R

ranges
during
full
throttle

operati
n

Notes

a

Temperature
of

torque
converter
oil
used
in
test
should

be
from
600

to
1000C
1400
to
2120F
i
e

sufficiently

warmed

up
but
not
overheated

b
To
cool
oil

between
each
stall
test
for
D
2
I

and
R

ranges
idle

engine
i
e

rpm
at
about
1
200

rpm
for
more
than
1
minute
in
P

range
Measurement

time
must
not
be
more
than
5
seconds

Same
as
item
I

Check
vehide

speeds
and

engine
cpm
in

shifting
up
Ist

2nd

range
and
2nd
Jo3rd
range
while

running
with
lever
in

D

range
and

engine
vacuum

pressure
of
about
200

I11I1lHg

Same

as
item
1
above

except
with

engine
vacuum
pressure

of
0

mmHg
i

e
in

position
just
before
kickdown

Check
whether
the
kickdown

operates
and
measure
the
time

delays
while

running
at
30
40
50
60
70
km
h
18
25
30

37
43
MPH
in

D3
range

AT

57