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EJU11062
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 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. 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.
Measure the spark plug gap a with a
wire thickness gauge. Replace the spark
plugs or adjust the gap to specification if
necessary.
To install the spark plug:
1. Clean the gasket surface.
2. Wipe any dirt from the threads of the
spark plug.
3. Install the spark plug, and then tighten it
to the specified torque.
4. Install the spark plug cap.Standard spark plug: BR8ES-11
Spark plug gap:
1.0–1.1 mm (0.039–0.043 in)
Spark plug tightening torque:
25 N·m (2.5 kgf·m, 18 ft·lb)
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NOTE:@ Wipe off any water on the spark plug or
inside the cap before installing the spark
plug cap. Push the spark plug cap down
until it is securely installed.
If a torque wrench is not available when
you are installing a new spark plug, a
good estimate of the correct torque is 1/4
turn to 1/2 turn past finger tight with the
spark plug wrench included in the tool kit.
Have the spark plug adjusted to the cor-
rect torque with a torque wrench as soon
as possible.
@
WARNING@ Be careful not to damage the insulator
when removing or installing a spark plug.
A damaged insulator could allow sparks
to escape, which could lead to an explo-
sion or fire.
@
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Page 104 of 122
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EJU11131
Adjusting the Yamaha
Adjustable Sponson (YAS)
The Yamaha Adjustable Sponsons can be
adjusted to enhance watercraft performance
according to operator preference and oper-
ating conditions. (See page 2-21 for an
explanation of various positions.)
To adjust the YAS:
1. Remove the bolts 1 on both sponsons.
2. Remove both sponsons, and then install
them in the desired position.
NOTE:@ Be sure to install both sponsons to the same
level.
@
3. Tighten the bolts on both sponsons to
the correct torque.
Tightening torque:
18 N·m (1.8 kgf·m, 13 ft·lb)
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