1977 DATSUN PICK-UP ECO mode

AUtomatic

trailamlsalon
modela

I

With
inhibitor

switch
ON
UN

or
P

position
check
for

presence
of

voltage
across
A
and
B
Refer
to

Figure
EF
51

If
voltmeter

ading
is

12
volts

d
c
B
C
D
O
circuit
is

func

tioning
properly

If
vol
tmeter

ading
is

zero
check

for
disconnected

connector

faulty

solenoid
valve

m
inhibitor

switch

2
With
inhibitor

switch
OFF

HI
2
IY
or
oR

position
Engine
Fuel

check

for
resistance

between
A
and
B

Refer

to

Figure
EF
51

If

ohmmeter

reading
is
25

ohms
or

below
circuit
is

functioning
prop

erly

If

ohmmeter

reading
is
32

ohms
or

above

check
for

poor
connection

of
connec
or

faulty
B
C
D
D
sole

noid
valve
or
inhibitor

relay

3

If

by
above
checks

faulty
part
or

unit
is

located
it

should
be
moved

and

tested

again
If

necessary
replace

yu
@

@
1

Ignition
key

2

Inhibit
T
switch

N
P

positions
ON

I

2
D
R

positions
OFF

3
D

C
D

D
solenoid
valve

4

Function
test
connector

5

Inhibitor

relay

EF712

Fig
EF
51

Checking
B
C

D
D
circuit
with

unction
t
st
connector

for
automatic
transmi
sion

Set

pressure

of

Boost
Controlled

Deceleration
Device
B
C
D
O

Generally
it
is

unnecessary
to
ad

just
the

B
CD
D

however
if

it
should

become

necessary
to

adjust
it
the

procedure
is
3S
follows

Prepare
the

foUowing
tool

I

Tachometer
to

measure
the
en

gine
speed
while

idling
and
a

screw

driver

2
A

vacuum

gauge
and

connecting

pipe

Note
A

quick
response

type
hoost

gauge
such
as
Bourdon
s

type
is

recommended
a

mercury
type

manometer

should
not
be
used

To

properly
set
the

B
C
D

D
set

pressure
proceed
as
follows

I
Remove

the
harness
of
solenoid

valve
To
B
D
D

solenoid
valve

1

B
C
D
D

olenoid

valve

harness

EF262

Fig
EF
52

Removing
harness

of

solenoid
valve

2

Connect
rubber
hose
between

vacuum

gauge
and
intake
manifold

as

shown

Fig
EF
53

Connecting
vacuum

gauge

EF
26
3

Warm

up
the

engine
until
it
is

heated
to

operating
temperature

Then

adjust
the

engine
at
nunnal

idling
setting
Refer
to
the

item

Idling

Adjustmenl
in

page
EF

21

Idling

engine
speed

Manual
transmission

750

rpm

Automatic
transmission

in
D

position

650

rpm

4

Run
the

engine
under
no

load

Increase

engine
speed
to
3
000
to

3
500

rpm
then

quickly
close
throttle

valve

5
At
the
time
the
manifold
vacuum

p
ssure
increases

abruptly
to

600

mmHg
23

62

inHg
or
above

and

then

graduaUy
decreases
to
the
level

set
at

idling

6
Check
that
the
B
C
D
D
set

pres

sure
is
within
the

specified
pressure

Specified

pressure
0
m
sea
level

and

760

mmHg
30

inHg
atmos

pheric

pressu

Manual
transmission

510

to
550

mmHg

20
1

to

21
7

inHg

Automatic
transmission

490
to

530

mmHg

19Tto
20

9

inHg

Notes

a
When

atmospheric
pressure
is

known

operating
pressure
will

be

found

by
tracing
the

arrow
line

A

See

Figure
EF
56

When
alti

tude
is
known

operating
pressure

will

be
found

by
tracing
the
arrow

line
B

See

Figu
EF
56

b

When

checking
the
set

pressu
of

B

CD
D
find
the

specified
set

pressu
in

Figure
EF

56
from
the

atmospheric
pressure
and
altitude

of

the

given
location

For

example
if

an
automatic
trans

mission
model
vehicle

is
located
at

an
altitude
of
1

000

m
3

280
ft

the

specified
set

p
ssu

for

B
C
D
D
is
445

mmHg
17

5

inHg

7
If
it
is

higher
than

the
set
level

turn
the

adjusting
screw
or
nut
until

correct

adjustment
is

made

Engine
Fuel

DISASSEMBLY
AND
ASSEMBLY

ff

C
oI

Q

f

@

ID
J

@
tJ

@
1
Lock
lever

2
Filter

set
screw

3

Fuel
filter

4
Fuel

nipple

5
Needle
valve

body

6
Needle
valve

7
Fuel

chamber

parts

8

Accelerating

pump
parts

9
Altitude

compensator
pipe

California
models

tng
ail

bleed

adJ

@

@1

@
A

Choke

chamber

B

Center

body

C
Throttle

chamber

I

J

@

EF725

EF30
11

High
speed
enricher
air
bleed

12
Choke

valve

13

Accelerating
pump
lever

14

Throttle
return

spring

15

Accelerating
pump
rod

16

Automatic

choke
cover

17
Automatic
choke

body
and

diaphragm
chamber

18
Richer

jet

19

Coasting
air
bleed
I

20

Primary
main

jet

21

Secondary
main

jet

22

Secondary
slow

air
bleed

23

Secondary
slow

jet

24

Plug

25
Air

bleed

26

Coasting
jet

27

Secondary
main
air

bleed

28
Power
valve

29

Primary
main
air

bleed

30

Plug

31

Primary
slow

jet

32
No
2

primary
slow

air
bleed

33

Primary
and

secondary
small

venturi

34
Venturi

stopper
screw

35
Choke

connecting
rod

36
Anti
dieseling

solenoid
valve

37
Fast

idle
cam

38

Diaphragm
chamber

parts

39
Idle

limiter

cap

40
Idle

adjust
screw

41
Idle

adjust
screw

spring

42
Throttle

adjust
screw

3

Thr9ttle

dj
t
5Crew

spring

44

Primary
and

secondary
throttle

valve

45

B
C
D
D

California

models

46
Vacuum

control
solenoid
valve

47
B
C

D
D
Non
Califomia

models

Note

Do
not
remove
the

parts

marked

with
an
asterisk

Ill

@ff

Fig
EF

62
Carburetor

part

Engine
Fuel

SERVICE
DATA
AND
SPECIFICATIONS

Airclelllcr

Ail
control
val

partially

opem

Air
ntrol
valve

fuUy
opens

Idle

ompensatoI

partially
opens

Hi
mettiNo

l

Bi
metal
No
2

Idle

ompen
tor

fully
opens

Bi
metal

No
1

Hi
metd
No
2

Fuels
Stem

Fuel

prtuure

Fuel

pump
apacHy

C
rbu
tor

C
rbu
tor

type

Carburetor
model
Oc

oF

oCe
F

oCe
F

Oc
OF

kpJcm2
poi

US

pt
min
at

rpm

Outlet
diameter

Venturi
diameter

Main

jet

Main
air
bleed

Slow

jet

Power
val

Float
level
U

fuel

preuure
rom
in

mm
in

mm

in

kg
cm2

psi

Adjustment

Engine
idling
Ignition
timing
Idle

speed
CO
at

mloro

Fuel
level

adjustment

Gap
between
Ive
stem
and
noat
at
mm

in

H

H

h

Fast
idle

adjwtmcnt
Fast
idle
earn

tint

step

Gap
between
throttle
IYe
and
carburetor

body

mm
in

Vacuum
break

adjustment

Gap
between
choke
alve
and
carburetor

body

mm

in

Choke
unloadel

adjusttncnt

Gap
between
choke
alw
and
carburetor

body

rom
in

Bi

metalsettinl

Bi
metal
resistance
at
2Ioe
700F

n

Bi
metalsettina

lnterloc
k

opcnina
of

primary
and

secondary

throtUc
valves
mmOn

Duh
pot

adjustment
without
loadin

I
m

Anti
diclClinasolenoid
valV
C

tiahtenina
torque

ka
m

in
lb

a
c
D
D
set

p
JSure

0
m
sea

level
and
760

mmHg

30
inlla
atmospheric
pressure
J
mmHa
inHg

R
C
D
D

tiahteninl
torque
kg
m

n
b
Nl
n
California
modell

Manual
transmiSsion

I
Automatic
transmission
California
modeb

Manual
transmission

I
Automatic
transmission

30
to
54
86
to
129

above

55
131
30
to
54
86
to
129

above
55

131

60
to
70

140
to
158

70
to
90

158
to
194
60
to
70

140
to
158

70
to
90

158
to
194

above
70

158

above
90

194
above
70

158

above
90

194

0
21
to
0
27
2
99
to
3
84

t
OOO

2
i
I
OOO
0
21
to
0
27
2
99
to

3
84

1
000
2
i
I
OOO

Strombcra
type

OCH340
7A
DCH340
48A
Stromt
rg

type

DCH34Q
45B
DCH340
46A

Primary
Secondary
Primary
Secondary
Primary
Secondary
Primary
Secondary

30
I8t

340
339
30
1
181
34
1
339
30
1
181

34
1
339
30
1

181
34
1
339

24
0
945

310
220
24
0
945
31
1
220
24
0
945
31
1
220
24
0
945
31
1
220

199
1160
199
1160
1101
1160
101

1160

170
160
170
160
170
60

170
1
60

148
1100
148
1100
148
1100
148
180

143
143
140
140

23
0
906
23
0
906
23
0
906
23

0
906

0
17
2
408
0
17
2
40B
0
17
2
408
0
17
2
408

1201750

rpm
CO

2
1
120

650

rpm
0

100
750rpm
C02
t
1
120
650

rpm
0

position
CO

2
t
1

position
CO
2
t
1

7
2

0
283
7
2
0
283
7
2
0
283
7
2
0
283

23
0
906
23

0
906
23
0
906
23
0
906

1
3
to
1
7
1

3
to

1
7
1
3
to

1
7
1
3
to
1
7

0
051
to
0
067
0
051
to
0

067
0
051
to
0
067
0
051
to
0
067

1
33
to
1
47
1
58
to
1
72
1
33
to

1
47
1
58
to
1
72

0
0524
to
0
0579
0
0622
to

0
0677
0
0524
to
0
0579
0
0622

to
0
0677

1
42
0
056
1
42
0
056
1
42
0
056
1
5
0
059

2
45
0
096
2
45
0
096
2
4
0
096
2
45
0
096

3
7
to

8
9
3
7
to
8
9
3
7
to
B
9
3
7
to
8
9

Center
of
the
ndex
mark
Center
of
the
index
mark

7
38
0
291
7
38
0

291
7
38
0

290
7
38
0
291

1
900
to

2
100
1
650
to

1
850
1
900
to
2
100
1
650
to

1
850

180
to
350

156
to
304
180
to
350

156
to
304
180
to
350

156
to

304
180
to
350

156
to
304

510
to

550
490
to

530
510
to
550
490
to
530

20
1
to
21
7
19
3
to

20
9
20
1
to
21
7
19
3

to
20
9

20
to
40

17
4
to
34
1
20

to
40

11
4
to
34
7
20
to
40

17
4
to
34
7
20
to

40
17
4
to
34
1

EF
35

Engine
Fuel

toms
and

causes
of
carburetor
troubles

and

remedies
for
them

are
listed
to

facilitate

quick
repairs

There
are
various
causes
of

engine

malfunctions
It
sometimes

happens

that
a
carburetor
which
has
no
fault
TROUBLE

DIAGNOSES
AND

CORRECTIONS

In
the

following
table
the

syml

Condition

Probable
cause

Overflow
Dirt
accumulated
on

needle
valve

Fuel

pump
pressure
too

high

Needle
valve

improperly
seated

Excessive
fuel

consumption
Fuel
overflow

Slow

jet
too

large
on
each
main

jet

Main
air
bleed

clogged

Choke
valve
does
not

open

fully

Outlet
valve
seat
of
accelerator

pump

improper

Linked

opening
of

secondary
throttle
valve

opens
too

early

Power

shortage
Main

jets
clogged

Every
throttle
valve
does
not

open
fully

Idling

adjustment
incorrect

FIICI
tr

clogged

Vacuum

jet

clogged

Air

c1eane

clogged

Diaphragm
damaged

Power
valve

operating
improperly

Altitude

compensator
setting
incorrect
Cali

fornia

models

Improper
idling
Slow

jet
clogged

Every
throttle

valve
does
not
close

Secondary
throttle
valve

operating
im

properly

Throttle
valve

shafts
worn

Packing
between

manifold
carburetor

fauJiy

Manifold
carburetor

tightening
improper

Fuel
overflow

B

C
D
D

adjustment
incorrect

Vacuum
control
solenoid

damaged

Stuck
anti
stall
dash

pot

EF

36
appears
to
have

some

problems
when

actually
the

electric

system
is
at
fault

Therefore
whenever

the

engine
is

mal

functioning
the
electrical

system

should
be
checked
rust
before

adjust

ing
carburetor

Corrective
action

Clean
needle
valve

Repair
pump

Re

place

See
condition
overflow

Replace

Clean

Adjust

Lap

Adjust

Clean

Adjust

AdjusL

pa
ir

Clean

Clean

Replace

Adjust

Correct
H
L
lever

position

Clean

Adjust

Overhaul
and

clean

Replace

Replace
packing

Correct

tightening

See
l
ondition
ov

rl1ow

Adjust

Replace

Replace

Condition

Engine
hesitation

Engine
does
not

start
Engine
Fuel

Probable

cause

Main

jet
or
slow

jet
clogged

By
pass
hole
idle

passage
dogged

Emulsion
tube

dogged

Idling
adjustment
incorrect

Secondary
throttle
valve

operating

im

properly

Altitude

compensator
setting
incorrect

Cali

fornia
models

Fuel
overflows

No
fuel

Idling

adjustment
incorrect

Fast
idle

adjustment
incorrect

Damaged
anti
dieseling
solenoid

EF
37
Corrective
action

Clean

Clean
tube

Clean

Adjust

Overhaul
and
clean

Correct
H
L
lever

position

See
condition
overflow

Check

pump
fuel

pipe
and
needle
valve

Adjust

Adjust

Replace

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

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

j

EC231

Thermal

vacuum
valva
o

o

m
Emission

Control

System

0

o

o

o

l

l
@

The
thermal
vacuum
valve

is

mounted
in

the

engine
thermostat

housing
It

detects

engine
coolan
t

tem

perature
by
means
of
a

built
in

bi

metal
and

opensor
closes
the

vacuum

passage
in
the

thermal
vacuum

valve

mt

li

t

00
t

EC232

Fig
EC
54
Thennal

vacuum
valve
To
E

G
R
control
valve

From
carburetor

1

Spring

2
Bi
metal

3

O

ring

E
G
R

warning

system

The

E
G
R

warning
system
install
1

Diaphragm
spring

2

Diaphragm

3
Valve
shaft

4

Valve

5
Valve

Seat

6
Valve
cham
ber

Fig
EC
53
E
G

R
control
value

When
the

vacuum

passage
is

open
the

carburetor
suction

vacuum
is

applied

to
the

diaphragm
of
the
E
G
R

con

trol
valve
to

actuate
the

taper
valve

connected
to
the

diaphragm

theconsiiiictlo

nlie
thermal

vacuum
valve
is

shown
below

ed

independently
of
the

E
G
R

con

trol

system
monitors

the
distance
the

car
has
travelled
and

indicates
when

EC
22
the
E

G
R

control

system
must
be

checked

The
E
G
R

warning
system
consists

of

an
odometer
switch

detector
drive

counter
E

G
R

warning

lamp
and

harnesses

When
the

earn
in
the

odom

eter
switch
connected
to

the

speed

ometer
turns

once
for

each
OAkm
4

mile
the

contact

point
of
the
elec

trica
circuit
closes

allowing
electric

current
to
flow

through
the

magnet

coil
of

the
detector

drive
counter

Thus

energized
the

magnet
coil
ac

Wates

the
latchet
to

turn
the
c
unter

wheel

by
one

pitch
When
the

number

of

counts
reaches
50
000
the
latchet

drops
in

a

groove
provided
on
the

periphery
of

the
counter
wheel
to

activate

the
detector

drive
counter

switch

Then
the

E
G
R

warning

lamp

comes
on

indicating
that
the
E
G
R

control

system
Should
be
checked

The

detector
drive

coun
teT
is

equip

ped
with
an
odometer
which

can
tell

when
to
service

the
E

G
R
contr0
I

system

After

completing

periodic
check

reset
the
odometer
to

zero
by
hand

proceeding
as
follows

1
Remove

grommet
installed
on

the
side

surface
of

detector
drive

counter
unit

2
insert

a
bar

or
a
screwdriver

tip

into
the

hole
from

which

grommet
has

been

removed
and

press
down
knob

provided
in

the
detector
drive
counter

for

resetting

The
E

G
R

warning

lamp
comes

on

under
the

following
circumstances

1
When
the
number
of

counts
has

reached
50
000
In
this

case
the

lamp

indicates
that
E

G
R

control

system

must
be
checked

2
When

operating
starter
motor

Notes

a
It
is

an
indication
of

problem
in

the

E

G
R

warning
lamp
or

problems

in
the

point
or
in
the
harnesses
if

the

lamp
does
not

light
at

50
000

counts

b

The
E

G
R

warning
system
is

mounted

on
all
620
models

except

those

bound
for
California
and

Canada