Cleaning And Adjusting The Spark Plugs - Yamaha WaveRunner FX140 2002 Owner's/Operator's Manual

EJU01820
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 plug peri-
odically; 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,
replace the spark plug with the specified
plug.
Removing the spark plug:
1. Remove the air filter case cover and air
filter element. (See page 4-14 for air filter
removal and installation procedures.)
2. Remove the spark plug.
Specified spark plug: NGK CR9EB
Measure the spark plug gap a with a
wire thickness gauge. Adjust the gap to
specification if necessary.
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
To install the spark plug:
1. Clean the gasket surface.
2. Wipe any dirt from the threads of the
spark plug.
3. Screw the spark plug to the correct
torque.
Spark plug tightening torque:
12.5 N·m (1.25 kgf·m, 9 ft·lb)
4-17
E