E
4-12
EMU12020
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
example, 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
yourself. 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 elec-
trode erosion becomes excessive, or if car-
bon 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.
6G8-9-1M-4 4/4/03 11:45 AM Page 13
To Next Page
Loading...
Need help?
General
