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EJU01100
Inspecting the oil injection
system
Check the oil injection system for leakage,
cracks, or malfunctions. If necessary, have a
Yamaha dealer repair the oil injection sys-
tem.
Check:
Oil tank for damage, cracks or leakage.
Oil tank for water or dirt.
Oil hose and joint for damage or cracks.
Oil filter for dirt.
Oil pump for leakage.
EJU01101
Oil tank
Check the oil tank for leakage or water in
the tank. If water is found in the oil injection
system or if the oil tank needs to be cleaned
have a Yamaha dealer service the water-
craft.
EJU01102
Oil filter
Check the oil filter 1 for dirt and clogs. If
the oil filter is clogged, remove it from the oil
tank together with the oil level sender and
clean it.
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EJU01891
Inspecting the jet thrust nozzle
angle
Check for smooth operation of the handle-
bars and jet thrust nozzle.
Turn the handlebars as far as possible to
the right and left and check that the distance
between the jet thrust nozzle and the hull
are equal on right and left sides.
If steering is stiff or misadjusted, have a
Yamaha dealer service it.Distance A and B: A=B
EJU01104
Inspecting and adjusting the
throttle cable
Check that the throttle cable moves back
to the set position smoothly and that free
play is within specification.
1. Squeeze and release the throttle lever. If
the lever does not return smoothly, have
a Yamaha dealer service it.
2. Adjust free play a by loosening the lock-
nut 1 and turning the adjuster 2.
Throttle lever free play:
4–7 mm (0.16–0.28 in)
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EJU01342
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: BR8HS
Spark plug gap:
0.6–0.7 mm (0.024–0.028 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.
@
EJU01139
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)
Choke cable (carburetor end)
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Throttle cable (handlebar end)
Squeeze the throttle lever and remove the
seal 1. Spray a rust inhibitor into the
outer cable. Refit the seal securely.
Steering cable (handlebar end)
Steering handle pivot shaft
If the steering pivot shaft becomes loose,
tighten the band 1 until a satisfactory feel
is obtained.
Steering cable (nozzle end)
Nozzle pivot shaft
Intermediate housing
Using a grease gun, fill the intermediate
housing with water resistant grease
through the grease nipple 1.
Grease capacity:
Initial 10 hours or 1 month:
33.0–35.0 cm
3 (1.11–1.18 oz)
Every 100 hours or 12 months:
6.0–8.0 cm
3 (0.20–0.27 oz)
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EJU01261
Adjusting the choke cable
Check that the choke cable is properly
adjusted.
1. Pull the choke knob out until it stops, and
then release the knob. The knob should
not move.
2. If the choke knob moves back on its own,
tighten the choke knob adjusting nut1
slightly. If the knob is difficult to move,
loosen the adjusting nut slightly.
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EJU01971
Inspecting the battery
Check the level of the battery electrolyte
and make sure that the negative and posi-
tive leads are securely tightened.
WARNING@ Battery electrolyte is poisonous and
dangerous, causing severe burns, etc.
Electrolyte contains sulfuric acid.
Avoid contact with skin, eyes, or cloth-
ing.
Antidotes
External: Flush with water.
Internal: Drink large quantities of water
or milk. Follow with milk of magnesia,
beaten egg, or vegetable oil. Call phy-
sician immediately.
Eyes: Flush with water for 15 minutes
and get prompt medical attention.
Batteries produce explosive gases.
Keep sparks, flame, cigarettes, etc.,
well away. If using or charging the bat-
tery in an enclosed space, make sure
that it is well ventilated. Always shield
your eyes when working near batter-
ies.
KEEP OUT OF THE REACH OF CHIL-
DREN.
Be sure to connect the breather hose
to the battery. Fire or explosion could
result if the breather hose is damaged,
obstructed, or not connected properly.
@
CAUTION:@ Be careful not to place the battery on
its side.
Be sure to remove the battery from the
battery compartment when adding
electrolyte or charging the battery.
@
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To replenish the battery:
1. Make sure that the electrolyte level is
between the upper 1 and lower 2 level
marks.
2. Refill the battery with distilled water if
necessary.
CAUTION:@ Normal tap water contains minerals that
are harmful to a battery. Use only dis-
tilled water for replenishing the battery.
@
To recharge the battery:
CAUTION:@ Do not attempt to charge a battery hast-
ily. Battery life could be shortened.
@
It is recommended to have a Yamaha
dealer charge the battery. If you charge the
battery yourself, carefully read the battery
charger instructions before charging and fol-
low the points below.
1. Remove all caps from the battery cell.
2. Add distilled water to the specified level if
the electrolyte level is low.
3. Set the charging rate to 1.9 ampere and
charge the battery slowly until the explo-
sive gases are discharged vigorously
from the battery cells.
To connect the battery terminals:
1. Make sure that the connections are cor-
rect when you install the battery in the
watercraft.
2. Make sure that the breather hose is
properly connected and that it is not
damaged or obstructed.
3. Make sure that the battery is securely
held in place.
1Positive (+): Red lead
2Negative (–): Black lead
3Breather hose
UF0M74.book Page 19 Wednesday, July 31, 2002 2:45 PM