adding oil DATSUN PICK-UP 1977 Service Manual

Page 21 of 537


Yellow

line

Spark
delay
valve
to

distributor

Spark
delay
valve
to
vacuum
tube

Distributor

to
vacuum
tube

Vacuum
tube
to
carburetor

Vacuum
tube
to
canister

Green
line

Anti

backfire
valve
to
intake
mani

fold

Air

control
valve
to

emergency
air

relief
valve

Intake
manifold
to
vacuum
hose

connector

Intake

manifold
to
canister

CHECKING
ENGINE

COMPRESSION

COMPRESSION
PRESSURE

TEST

I
Warm

up
engine
sufficiently

2
Disconnect

all

spark
plugs

3
Disconnect
anti

dieseling
solenoid

valve
connector

4

Properly
attach
a

compression

tester
to

spark

plug
hole
in

cylinder

being
tested
Engine
Tune

up

I

ET010
Different

compression
in
two
or

more

cylinders
usually
indicates

an

improperly
seated
valve
or
broken

piston
ring

9
Low

compression
in

cylinders
can

result
from
worn

piston
rings
This

condition

may
usually
be

accompanied

by
excessive

fuel

consumption

TEST
RESULT

If

compression
in

one
or
more

cylinders
is
low

pour
a
small

quantity

of

engine
oil
into

cylinders
through

the

spark
plug
holes
and
retest
com

pression

I

If

adding
oil
increases
the
com

pression
pressure
the
chances
are
that

rings
are

faulty

2

If

pressure
stays
low

probable

cause
is

that
valve
is

sticking
or

seating

improperly

3
If

cylinder
compression
in

any

two

adjacent
cylinders
is

low
and
if

adding
oil
does
not

help
the

compres

sian
there
is

leakage
past
the

gasket

surface

Oil
and
water
in

combustion
cham

bers

can
result
from

leakage

IGNITION
AND

FUEL
SYSTEM
Fig
ET
10

Teding

compression

pressure

5

Depress
accelerator

pedal
to

open

throttle
and
choke
valves

Note
Do

not

pump
pedal

6
Start

engine
as

quickly
as

pos

sible

7

Compression
pressure

kg
cm2

psi
at

rpm

Standard

12
0

171
350

Minimum

9

0
128
350

8

Cylinder
compression
in

cylinders

Should
not
be
less
than

80
of

highest

reading

CONTENTS

CHECKING
BATTERY
ET
9

CHECKING
DISTRIBUTOR
CAP
ROTOR

CHECKING
AND

ADJUSTING
IGNITION
AND
CONDENSER
ET
11

TIMING
ET
10

CONDENSER
ET
11

ADJUSTING
IGNITION
TIMING
ET10

ADJUSTING
CARBURETOR
IDLE
RPM

CHECKING
AND
REPLACING
SPARK
PLUG
ETlO
AND
MIXTURE
RATIO
ET

11

CHECKING
DISTRIBUTOR
OPERATING
IDLE

LIMITER
CAP
ET
12

PARTS
AND

IGNITION
WIRING
ETlO
CHECKING
CARBURETOR
RETURN
SPRING
ET

12

BREAKER
POINTS

lNon
California
models

ET
10
CHECKING
CHOKE
MECHANISM

AI
R

GAP
lCalifornia
models
ET11
Choke

plate
and

linkage
ET13

DISTRIBUTOR
ET
11
CHECKING
FUEL

LINES

IGNITION
WIRING

ET
11
Hoses

pipings
connections
etc

ET
13

REPLACING
FUEL
FILTER
ET
13

CHECKING
BATTERY

Check

electrolyte
level
in

each
bat

tery
cell
I
Unscrew

each
filler

cap
and

inspect
fluid
level
If
the
fluid
is
low

add
distilled
water
to

bring
the
level

up
approximately
10
to
20
mm
0
39

H
9
to
0
79

in
above
the

plates
Do
not

overfill

2
Measure
the

specific
gravity
of

battery
electrolyte

Page 177 of 537


No
load
test

Connect

starting
motor
in

series

with

specified
12
volts

battery
and

an
ammeter

capable
of

indicating

1

000

amperes

Starter
motor

Diagnoses
of
test

1
Low

speed
with

no
load
and

high

current
draw

may
result
from
the

following

1

Tight
dirty
or
worn

bearings

2

Bent
armature
shaft
or
loosened

field

probe

3
Shorted
armature

Check
armature
further

4

A

grounded
armature
or
field

a
Remove

input
tenninal

b

Raise
two

negative
side
brushes

from
commutator

c

Using
a
circuit
tester

place
one

probe
onto

input
tenninal
and
the

other
onto

yoke

d
I

f
tester
indicates

continuity

raise
the

other
two
brushes
and
check

field
and
armature

separately
to

determine
whether
field
or
armature
is

grounded

2
F

allure
to

operate
with

high

current
draw

may
be

caused

by
the
Engine
Electrical

System

Specified
current

draw
and

revolu

tion
in

these
test
are

shown
in

Specifications

Switch

6
Battery

Et

Voltmeter
Ammeter

Ee026

Fig
EE
20
No
load

l
ting

following

I
A

grounded
or

open
field
coil

Inspect
the
connection
and
trace

circuit
with

a
circuit
tester

2
Armature
coil
does
not

operate

Inspect
commutator
for
excessive

burning
In
this
case
arc

may
occur
on

damaged
commutator
when
motor
is

operated
with
no
load

3
Burned
out
commutator
bar

Weak
brush

spring
tension
broken

brush

spring
rubber
bush
thrust
out

of
mica
in

commu
tat
or
or
a
loose

contact
between
biush
and
com

mutator
would

cause
commutator
bar

to
burn

3
Low

current
draw
and
low

no
load

speed
would

cause

high

internal
resistance

due
to
loose
con

nections

damaged
leads

dirty
corn

mutator
and
causes
listed
on
item

2

3

EE10
MAGNETIC
SWITCH

ASSEMBLY
TEST

Switch

o

Fv
IB
I

I

D

Battery
Starter
motor

EE351

FiN
EE

21
Circuit

ofmagndic
awitch

assembly
ted

If
the

starting
motor
check
is

OK
check

magnetic
switch
as

sembly
Connect
cables

between

negative
battery
tenninal

and
start

ing
motor
M
terminal

positive

battery
terminal
and

starting
motor

S
terminal

connecting
a
switch
in

series
as

shown
in

Figure
EE

21

With
the
switch
on

push

pinion

back
to

remove
all
slack
and

measure

the
clearance
l
between

pinion

front

edge
and

pinion
stopper
The

clearance
should
be

held
within
0
3
to

1
5
mm

0
012
to
0

059
in

If
neces

sary
adjust
it

by
changing
or

adding

adjusting

washer
s

Adjusting
washers

are
available
in

to
two

different
sizes

0
5
mm
0

020
in

and
O
S

mm
0
031

in

0
3
to
I
S
rom

0
012
to
0
059
in

l

EE029

Fig
EE
22
MeO

uring
clearance

t