Yamaha FX High Output WaveRunner 2004, Owner'S/Operator'S Manual

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4-15
E
EJU21070
Cleaning and adjusting the
spark plugs
The spark plug is an important engine
component and is easy to inspect. The con-
dition of the spark plug can indicate some-
thing about the condition of the engine. For
example, if one spark plug shows a distinctly
different color, the engine could be defec-
tive. Do not attempt to diagnose any prob-
lems yourself. Have a Yamaha dealer
service the watercraft.
Remove and inspect the spark plugs peri-
odically; heat and deposits will cause the
spark plugs to slowly break down and erode.
If electrode erosion becomes excessive, or if
carbon and other deposits are excessive,
replace the spark plug with the specified
plug.
Removing a spark plug:
1. Remove the air filter case cover and air
filter element. (See page 4-13 for air filter
removal and installation procedures.)
2. Remove the spark plug cap.
CAUTION:
@
Do not use any tools to remove or install
the spark plug cap, otherwise the igni-
tion coil coupler may get damaged. The
spark plug cap may be difficult to remove
because the rubber seal on the end of
the cap fits tightly. To remove the spark
plug cap, simply twist it back and forth
while pulling it up; to install it, twist it
back and forth while pushing it down.
@
3. Remove the spark plug.
Specified spark plug: NGK CR9EB
UF1S10.book Page 15 Wednesday, December 17, 2003 1:11 PM