Checking The Spark Plugs - Datsun 320-U Service Manual

CHECKING
THE
SPARK PLUGS
t
Spark
Plug
r
Type
Thread dIameter
Plug
gap
N
G
K
B
6
E
14
mm
O
60 O 8
mm
The
spark
plug
has the functIOn of
Igmtlng
the
aIr
fuel
mIxture
wIth the
spark
whIch
Jumps
between
Its
electrodes
Dunng
Its
operatIOn
It IS
subJected
to ex
tremely hIgh
temperature
and
pressure
If
thIs vehIcle
NGK Model B
6E
Spark
plugs
are
used Care should be
taken
to
see
that the
specIfIed spark plugs
are
always
used for
replacement
Spark plugs
are
apt
to
become
dIrty
with
deposits
of carbon and
011
droplets
whIch may
cause leakage
or
shonng
between the delecto
rodes
Furthermore
the
spark plugs
are
sub
Ject
to wear after
long use
Therefore
remove
the
plugs
every
2 000 km 1 200 mIles of dnv
mg clean them and
measure
and
correct
theIr
gaps
to
O 6
to
O 8
mm
In
correcting
thl
gaps
always
be
sure
to
bend
only
the
grounp 9Iae
electrode
never
bend the
center
electrode If
the
msulator
IS
damaged
replace
the
spark
plug
A
wIre
feeler
type
plug
gap gauge
should
be used
When
screwmg
m
the
spark
plugs be
sure
not to forget
the copper
washers If these have
been flattend
out or are worn they
WIll
not
be
gas
tight
and
WIll
cause
such trouble
as mter
ference with the
dISSIpation
of heat To
mstall
a spark
plug
fIrst
screw It
m
as
far
as It
WIll
go
by
hand
then
fmally tighten
It by means
of
a
socket wrench The
use
of such unsUItable
tools
as an
adjustable
wrench
may
crack the
msulator Each
spark plug must
be
tightened
securely
yet
not too tight
Any
dIrt
011
or
such
Impuntles
adher
mg
to
the outsIde of the
spark
plugs
WIll
ImpaIr
theIr
performance
Therefore
frequently
clean the
spark plugs by
wlpmg
WIth
a
pIece
of
clean cloth
65
@
Q
Spark Plug
Section
1
2
3
4
5
Center electrode
Ground SIde electrode
Gap
Insulator
porcelam
Cyltnder
head
I