1977 DATSUN PICK-UP ESP

CLEANING
AND

INSPECTION

Dirt

gum
wuler
or
l
arbon
con

taminatiun
in

or
on
exterior

moving

parts
of
a

arburctor
arc
often

respon

sihk
for

unsatisfactory
performance

For
this

reason
efficient
carbutetioll

dcpends
upon
careful

cleaning
and

inspection
while

servicing

I

Blow
all

passages
and

castings

with

compressed
air

and
blow
off
all

parts
until

dry

Note
Do
not

pass
drills

or
wires

through
calibrated

jet
or

passaaa

as
this

may
enlarge
orirlce
and

seriously
affect
carburetor
calibrs

lion

2

Check
all

parts
for
wear
If
wear

is

noted
damaged

parts
must
be
re

placed
Note

especially
the

following
Engine
Fuel

I
Check
float
needle

and
seat
for

wear
If
wear
is

noted

assembly
must

be

replaced

2
Check
throule
and
choke
shaft

bores
in
throtlle
chamber
and
choice

chamber
for
wear
or

out
of
roundness

3
Inspect
idle

adjusting
needle
for

burrs
or

ridges
Such
a

condition
re

quires
replacemen
1

3

Inspect
gaskets
0
see
if

they

appear
hard
or
briUle
or

if

edges
are

torn
or
distorted
If

any
such
condi

tion
i
noted

they
must
be

replaced

4
Check
filter
screen
for
dirt
or
lint

Clean
and
if
screen
is
distorted
or

remain

plugged
replace

5
Check

linkage
for

operating

condition

6

Inspect
operation
of

accelerating

pump
Pour
f
el
into

jloat
chamber

and
make
throtlle
lever

operate
Check

condition
of
fuel

injection
from

the

EF
34
accelerating
nowe

7

Push
connecting
rod

of
dia

phragm
chamber
and
block

passage
of

vacuum
with

finger
When

connecting

rod
becomes
free
check
for

leakage
of

air

or

damage
to

diaphragm

Jets

Carburetor

performance
depends

on

jet
and
air
bleed
That
is

why

these

components
must
be

fabricated

with
utmost
care
To

clean
them

use

cleaning
solvent
and
blow
air

on
them

Larger
inner
numbers

tamped
on
the

jet
indicate

larger
diameters
Ac

cordingly
main
and

slow

jets
with

lalger
nUmbers

provide
richer
mixture

the
smaller
the
numbers
the
leaner
the

mixture
Conversely
the
main
and

slow
air
bleeds

through
which
air
to

passes
through
make
the
fueLleaner
if

they
bear

larger
numbers
the
smaller

the
numbers

the
richer

the
fuel

Emission
Control

System

EARLY

FUEL

EVAPORATIVE

SYSTEM
E

F
E

DESCRIPTION
spring
and

counterweight
which
are

assembled
on
the

valve
shaft

projecting

to
the

rear
outside
of
the
exhaust

manifold
The

counterweight
is
se

cured
to
the
valve
shaft
with

key
bolt

and

snap
ring
EC
4
A

control
valve
welded
to

the

valve
shaft
is

wtalled
on
the

exhaust

manifold

through

bushing
This
con

trol

valve
is

called
Heat

control

valve
The
heat
control

valve
is

ac

luated

by
the

coil

spring
thermostat
Construction
of
the

early
fuel

evap

orative

system
is

shown
in

Figure

r
I

1

@

rW

9

Sc
w

10
Thennostat

spring

11

Coil
spriiig

12
Control
valve
shaft

13
Heat
control

valve

14

Bushing

15

Cap

16
Exhaust
manifold
1
Intake
manifold

2
Stove

gasket

ManifoktstOve

4
Heat
shield

plate

5

Snap
ring

6

Counterweight

7

Key

g

Stoppel
pin

EC532

Fig
EC
4
Early
Fuel

Evaporutive
tem
E
F
E

The

early
fuel

evaporative
system
is

provided
with
a
chamber
above

a

manifold
stove
moonted
between
the

intake
and
exhaust

manifolds

During

engine

warming
up
air
fuel
mixture
in

the

carburetor
is

heated
in
the
cham

bet

by
exhaust

gases
This
results
in

improved
evaporation
of

atomized
fuel

droplets
in
the
mixture
and
in

smaller

content
of

hydrocarbons
He
in
the

exhaust

gas
especially
in

cold
weather

operation

The
exhaust

gas
flow
from
the

engine
is

obstructed

by
the
heat
con

trol

valve
in
the

exhaust
manifold
and
is

changed
in

direction
as
shown

by

the
solid

lines
in

Figure
EC
4
The

exhaust

gas
heats
the
manifold
stove

Open
close

operation
of
the

heat

control
valve
is
controlled

by
the

counterweight
and
thermostat

spring

which
is
sensitive
to
the

ambient
tem

perature
around
the

exhaust
manifold
With
this
condition
the

heat
control

valve
is
in

the

fully
closed

position

obstructing
the
flow
of

exhaust

gas
As

engine
tempera
lure

goes
up
and

the

ambient

temperature
becomes

high

enough
to
actuate
the
thermostat

spring
the

counterweight
begins
to

rotate
clockwise
and

again
comes
into

con

tact
with

the

stopper
pin
With
this

condition
the

heat
control
valve
is
in

the
full

open
position
and
exhaust

gas

passes
through
the
exhaust
manifold
as

shown

by
the
dotted

lines
in

Figure

EC
4
without
heati

ng
the
manifold

stove
OPERATION

The

counterweight
rotates
counter

clockwise
and

stops
at

the

stopper
pin

mounted
on
the
exhaust

manifold

while

the

engine
temperature
is
low

EC
6

Air
control
valve

CalifornIa
models

The
air
control
valve

con
troIs
the

quantity
of

secondary
air
fed

from
the

air

pump
according
to

engine
speed

and

load
condition
and

prevents
ex

cessive

temperature
rise
of
the

cataly

tic
converter

The
construction
is
as
shown
in

Figure
EC
16
The
intake
manifold

vacuum
and
air

pump
discharge
pres

sure

applied
to

the

diaphragm
chamber

actuate
the

valve
which
is

coupled
to

the

diaphragm
and
control
the

quanti

ty
of

secondary
air
to
be
fed
into
the

exhaust
manifold
in

response
to
the

engine
condition

c
From

air

pump

To

carburetor

air
cleaner

lr

J

EC291

Fig
EC
16
Air
control
valve

Anti
backfire
valve

This

valve
is

con
trolled

by
intake

manifold
vacuum
to

prevent
backfire

in
the

exhaust
system
at

the
ini

tial

period
of
deceleration

At
this

period
the
mixture
in
the

intake
manifold
becomes
too

rich
to

ignite
and
burn
in
the

combustion

chamber
and
burns

easily
in
the
ex

haust

system
with

injected
air
in
the

exhaust
manifold

The
anti
backfire
valve

provides
air

to
the
intake
manifold
to
make
the

air
fuel
mixture
leaner
and

prevents

backfire

A
schematic
drawing
of
the
anti

backfire
valve
is
shown
in

Figure

EC
17

The
anti
backfire
valve
inlet
is

con

nected
to
the
air
cleaner
and
the

outlet

to
the
intake
manifold

Th
correct
function
of
It
jS
valve

reduces
hydrocarbon
emission

during

aeceleration

If
the
valve
does
not
work

properly

unburned
mixture
will
be

emitted
Emission
Control

System

from
the
combustion
chambers
and

burns
with
the
aid
of
high

temperature

and

injected
air

which
causes
backfire

I
Tointake

c
manifold

vacuum

I

L

AirdisChaJ1le

I

to
mtake

manifold
From
air

cleaner

ECQ69

Fig
EC
11
Anti
back
ir
valve

Check
valve

A
check
valve
is
located
in
the
air

pump
discharge
lines
The
valve

pre

ven
ts
the
backflow
of
exhaust
gas

which
occurs
in

one
of
the

following

cases

1
When

the
air

pump
drive
belt

fails
2
When
relief
valve

spring
fails

Construction
is

shown
in

Figure

EC

18

F
rom

m

pump

1

Spring

2

Rubber
valve

3

Seat
Secondary
air

Exhaust

gas

EC292

Fig
EC
1B
Check
valve

AIr

InJaction
Into
axhaust

port

The

secondary
air

fed
from
the
air

pump
goes
through
the

check
valve
to

the
air

gallery
where
it
is
distributed
to

each
exhaust

port
The

secondary
air

is
then

injected
from
the
air

injection

nozzle
into

the
exhaust

port
near
the

exhaust
valve

n

L
y

r

V

Air
pump
relief
valve

The
air

pump
relief
valve

controls

the

injection
of
the

secondary
air
into

the
exhaust

system
when
the

engine
is

EG
11
3
I
Air

gallery

2

Exhaust
port

3
Air

jnjection
nozzle

4
Exhaust

manifold

EC293

Fig
EC
19
Air
injection
into
exhaust

port

running
at

high
speed
under
a

heavily

loaded
condition
It

accomplishes
the

following
functions
without

affecting

the

effectiveness
of
the
exhaust
emis

sion
control

system

6

Thermal
vacuum
valve

Open

E
G
R
control
valve
Close

E
G
R
ON

operation

The
E
G
R
circuit
is

completed

only
when

engine
coolant

temperature
Emission
Control

System

I

I
Note
Vacuum
condition

EC793

Fig
EC
51
E
G
R
not
actuated

is
above
the

working
temperature
of

the

thermal
vacuum
valve
and
carbu
retor
suction
vacuum
is

large
enough

to

open
the
E
G
R

control
valve

Y
m
l

fj

t1f
1t
3
0

l

P
@
0
f
Y
f

1
i0
W
g

1
i3
iiA
d

m

E
N
ti

n
k

i

l
i
Throttle
valve

n

L
r

E

G
R

control
valve

Open

E
G
R
control
valva

The

E
G
R

control
valve
controls

the

quantity
of
exhaust

gas
to
be
led

to
the

intake
manifold

through
vertical

movement
of
the

taper
valve
connect

ed

to
the

diaphragm
to
which

vacuum
Thermal
vacuum

valve

Open

Note

iiiI
Vacuum
condition

EC794

Fig
EC
52
E
G
R
actuated

is

applied
in

response
to
the

opening

of
the
carburetor
throttle
valve
The

E
G
R
control
valve
is
installed
on
the

E
G
R

passage
through
a

gasket

E
G
R
con
trol
valve
construction

and

type
vary
with

transmission

type
and

car
destination
For
identification

purposes
the

part
number
is

stamped

on
the
recessed

portion
at
the

top
of

the
valve

The

construction
of
the
E
G
R

control
valve
is

shown
below

EC
21

EC350

Fig
EC
65

Cleaning
E

G
R
control

valve

Thermal

vacuum

valve

Dismount
thermal

vacuum
valve

from

engine

Note
Before

dismounting
drain
en

gine
coolant

from

engine

Apply
vacuum
to
thermal
vacuum

valve
and

check
to
be
sure
thaI
ther

mal
vacuum
valve

opens
or
closes
in

response
to

engine
coolant

tempera

ture
as

specified

Thermal
vacuum
valve

should

open

at
a

temperature
of
57
to
630C

135

to
1450F

completing
the

vacuum

passage

Note
Do

not
allow
water
to

get

inside

the
thermal
vacuum
valve

EC242

Fig
EC
66

Checking
hennal

vacuum

valve
Emission
Control

System

CATALYTIC

CONVERTER

DESCRIPTION

The

catalytic
converter
accelerates

the
chemical
reaction
of

hydrocarbons

HC
and
carbon
monoxide
CO
in

the

exhaust

gas
and

changes
them
into

non
harmful

carbon
dioxide

C02

OPERATION

Exhaust

gas
emitted

from
the
en

gine
contains

some
harmful
substances

due
to

incomplete
combustion
in
the

combustion
chamber
The

air

injection

system
is

designed
to

reduce
the
con

tent
of
such
substances
in

the
exhaust

gas
In

this

system
the

secondary
air

is

led
from
the
check
valve

and

injected

into
the

exhaust
manifold

With
this

injection
of
the

secondary
air

hydro

EC444

EC
26
and
water

H20
This
chemical
reac

tion

process
requires
the

proper
a

mount

of
air

which
is

supplied
by
the

air

pump
Refer
to

the
item
AJ

S

This
air
is
caUed

secondary
air

The

catalytic
converter
is
mounted

on
the

vehicles
destined

for
California
Refer

to

Figure
EC
67

3
4

1
Front
tube

2

Catalyti
converter

3
Center
tube
4
Main
muffler

5
Rear
tube

EC782

Fig
EC
67

Location

of
catalytic
converter

car

ons

He
and
carbon

monoxide

CO
in
the
exhaust

gas
are

gradually

oxidized
with

oxygen
02
in
the

secondary
air
and
converted

into
non

harmful
carbon

dioxide

C02
and

water

H20

The

catalytic
converter

further

cleans

engine
exhaust

gas
Through

catalytic
action
it

changes
residual

hydrocarbons
and
carbon
monoxide

contained

in
exhaust

gas
into
carbon

dioxide

and
water
before

exhaust

gas

is

discharged
to
the

atmosphere

c
Secondary
air

Carbon
monoxide

hydrocarbon

Carbon
dioxide
gas

water

F
EC
68

Operution
of
catalytic
corwerter

If
the
result

is
N
C
Take

the

following
measures

I
Check
BW
and
B
color

wire

harness

respectively
for

proper
con

ductance

2

Check

battery
terminals

for

proper
connection

3
Check

charge
condition
of
bat

tery
if
an

excessively
low

voltage
is

indicated

2

CONTINUITY
CHECK
OF

PRIMARY
CIRCUIT

2
1

CheckIng
prImary

circuit
See

wiring

diagram

In

Fig
EE
89

Proced
ure

I

Disconnect

L
color
wire

from

ignition
unit

2

Turn
on

ignition
switch

3

C
ooneet
a
cireui
t

tester
or
an

oscilloscope
as
shown
in

Figure
EE
78

DC

50
volt

range

tf
S

EE303

Fig
EE

78
Checking
primary
circuit

Criterion

When

Donnal

power
Source

battery

voltage
is

indicated

OK

Lower

or
no
indication

N

G

If
the

result
is

N
C

Take

the

following
measures

1

Check
BW

and
L
color

wire
Engine
Electrical

System

harness

respectively
for

proper
con

ductance

2

Check
resistor

and

ignition
coil

terminals
for
loose

contact

3

Check
resistor
and

ignition
coil

for

discontinuity

4
Check

WB

color
wire
harness

of

ignition
coil

assembly
for

proper

continuity

2
2

Chacklng
IgnitIon
coil

auembly
See

wiring

diagram
In

Fig
EE
90

Procedure

I

Disconnect

ignition
coil
and
dis

tributor

harness
from

ignition
coil

external
resistor

2

Connect
a
circuit
tester
as

shown

in

the

figure
below

Resistance

1

range

Q

o
fD

ro

EE336

Fig
EE
79

Checking
ignition
coil

assembly

Criterion

When

approximately
1
6

to

2

0

ohm
is

indicated

OK

More

than
2

0
ohm

N
C

If
the

result
is

N
C

Replace

ignition
coil

assembly

3
PICK

UP

COIL

CONTINUITY

CHECK

See

wirIng
dIagram
In

Figure
EE
91

Procedure

Disconnect
R

and
G

color

wires
from

ignition
unit

2
Connect

a
circuit

tester
as
shown

in
the

figure
below

EE

3B
Resistance

10

range

fp

EE305

Fig
EE

BO

Checking
pick
up
coil

Criterion

When

approximately
720
ohm

is

indicated

OK

Far
less
than
or
more

than

720
ohm
N
C

If

the
result
is
N
C

Replace

pick

up
coil

assembly

4

PICK
UP
COIL
POWER

SIGNAL

PULSE
CHECK

Procedure

I

Disconnect
anti

dieseling
solenoid

valve

connector

2

Connect
a
circuit

tester
as

shown

in

the

figure
below

3

Rotate
starter

motor

4

Read
the
tester
indication

AC
2
S
volt

range

EE306

Fig
EE
81

Checking
pick
up
coil

power

aignal
pulse

Criterion

When

pointer
deflects

slightly
OK

When

pointer
does
not
deflect

at
all

N
C

If
the

result
is

N
C

Replace

pick

up
coil

assembly

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

5

Apply
a

light
coat

of
multi

purpose
grease
to

withdrawal
lever

release

bearing
and

bearing
sleeve
in

stall
them
on
clutch

housing

After

connecting
them

with
holder

spring
instaU
dust

cover
on
clutch

housing

6
Install
control
lever

temporarily

and

shift
control

lever

through
all

gears
to
make

sure

that

gears

opera
Ie

smoothly

Note
Install

drain

plug
and
filler

plug

ith
sealant
in

place
Manual

Transmission

INSTALLATION

Install
the
transmission
in
the
reo

verse
order
uf
removal

paying
atten

tion

to
the

following

points

1
Before

installing
dean

mating

surfaces
of

engine
rear

plate
and

trans

mission
case

2

Before

installing
lightly
apply

grease
to

spline
parts
of
clutch
disc

and
main
drive

gear

3

Tighten
bolts

securing
trans

mission

to

engine
to

specifications
See

Figure
MT
55

5
SPEED
TRANSMISSION

TYPE

DESCRIPTION

REMOVAL

DISASSEMBL
Y

TRANSMISSION
CASE
DISASSEMBLY

DISASSEMBL
Y
OF
GEAR

ASSEMBLY

REAR

EXTENSION
DISASSEMBLY

ADAPTER
PLATE

DISASSEMBLY

INSPECTION

TRANSMISSION
CASE
AND
REAR

EXTENSION
HOUSING

DESCRIPTION

The
transmission

is
of
a
5

speed

forward
with
overdrive
4

OD

speed

fully
synchronized
constant

mesh

type
that

uses
helical

gears

The
5

speed
transmission
covered
in

this
section
is

similar
in

all

respects
to

the
4

speed
transmission

type

F4W71B
stated

previously
except
the
CONTENTS

MT14

MT17

MT17

MT17

MT17

MT18

MT19

MT19
4
4

to
5
9

kg
m

32
to
43
ft
Ib

1

0
9
to
1
2

kg
m

7
to
9
rt
lb
TM773

Fig
MT
55

Tightening
torque

4
Remove
filler

plug
and
fIll
trans

mission
with
recommended

gear
oil

to

the
level
of
the

plug
hole

Approxi

mately
I
7

liters
3

pt
3

pt

FS5W71B

BEARING

GEARS

AND
SHAFTS

BAULK

RING

OIL

SEAL

ASSEMBL
Y

FRONT
COVER
ASSEMBLY

REAR

EXTENSION

ASSEMBLY

GEAR

ASSEMBLY

TRANSMISSION
ASSEMBLY

INSTALLATION
MT19

overdrive

position
of
it

The

overdrive

gear
rides
on
the

mainshaft

freely
through
the

needle

roller

bearing
and
counter

overdrive

gear
is
fitted
to
the

countershaft

by

splines

The
overdrive

synchronizer
system

is

on
the
mainshaft
rear
side

MT14
MT19

MT19

MT19

MT19

MT19

MT19

MT19

MT19

MT

20

MT20

Placing
the
control
lever
in

over

drive

position
brings
the
reverse
OD

coupling
sleeve
reverse

gear
on
main

shaft
into
mesh
with
overdrive
clutch

gear
The
reverse
OD

synchronizer

hub
is

fItted

to
the
mainshaft

by

splines
so
the
overdrive

gear
on
main

shaft

turns

together
with
the
main

shaft