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EJU01341
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 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.
Measure the spark plug gap a with a
wire thickness gauge before installing the
spark plug. Adjust the gap to specification if
necessary.
To reinstall 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. Standard spark plug: BR8ES
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Spark plug 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 clicks.
If a torque wrench is not available when
you are fitting a new spark plug, a good
estimate of the correct torque is 1/4 turn
to 1/2 turn past finger tight. Have the
spark plug adjusted to the correct 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 explosion
or fire.
@
EJU01141
Lubrication points
To keep moving parts sliding or rotating
smoothly, coat them with water-resistant
grease.
Recommended water resistant grease:
Yamaha Marine Grease/
Yamaha Grease A
Throttle cable (carburetor end)
Oil pump cable
Choke cable (carburetor end)
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EJU01113
Adjusting the Yamaha
Adjustable Sponson (Y.A.S.)
The Yamaha Adjustable Sponsons can be
adjusted to enhance watercraft performance
according to operator preference and oper-
ating conditions. (See page 2-19 for an
explanation of various positions.)
To adjust the Y.A.S.:
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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