SparkPlugService
_
WARNING:
DO NOT check for spark with spark
plug removed.
DO NOT crank engine with spark
plug removed.
To ensure proper engine
operation,
the spark plug must be
properly
gapped
and free of deposits.
1.
Remove the spark plug boot and use a spark plug wrench
to remove the plug. See Fig. 10-3.
Spark Plug
Spark Plug Boot f
Figure
10=3
i_
WARNING:
If the engine has been running,
the
muffler
will be very hot. Be careful not to touch the
muffler.
2.
Visually inspect the spark plug. Discard the spark plug
if there is apparent
wear, or if the insulator
is cracked
or
chipped.
Clean the spark plug with a wire brush if it is to be
reused.
3.
4.
5.
Measure the plug gap with a feeler gauge. Correct as
necessary by bending
side electrode.
See Fig. 10-4. The
gap should
be set to 0.030 in.
Electrode
0.030 in.
Figure 10=4
Check that the spark plug washer
is in good condition
and thread the spark plug in by hand to prevent
cross-
threading.
After the spark plug is seated, tighten
with a spark plug
wrench
to compress
the washer.
NOTE:When
installing
a new spark plug, tighten
1/2 turn
after the spark plug seats to compress
the washer. When
reinstalling
a used spark plug, tighten
1/8-1/4 turn after the
spark plug seats to compress the washer.
IMPORTANT:The
spark plug must be securely tightened.
An improperly
tightened
spark plug can become
very hot
and may damage
the engine.
SECTION 10
--
ENGINE MAINTENANCE
21