E
4-12
EMU01202
CLEANING AND ADJUSTING SPARK
PLUG
w
When removing or installing a spark
plug, be careful not to damage the insu-
lator. A damaged insulator could allow
external sparks, which could lead to
explosion or fire.
The spark plug is an important engine com-
ponent and is easy to inspect. The condition
of the spark plug can indicate something
about the condition of the engine. For exam-
ple, if the center electrode porcelain is very
white, this could indicate an intake air leak
or carburetion problem in that cylinder. Do
not attempt to diagnose any problems your-
self. Instead, take the outboard motor to a
Yamaha dealer. You should periodically
remove and inspect the spark plug because
heat and deposits will cause the spark plug
to slowly break down and erode. If electrode
erosion becomes excessive, or if carbon
and other deposits are excessive, you
should replace the spark plug with another
of the correct type.
Before fitting the spark plug, measure the
electrode gap with a wire thickness gauge;
adjust the gap to specification if necessary.
Standard spark plug:
Refer to “SPECIFICATIONS”, page 4-1.
Spark plug gap:
Refer to “SPECIFICATIONS”, page 4-1.
63V-9-K0A0-4B 4/4/02 4:54 PM Page 2
To Next Page
Loading...
Need help?
General
