2021 YAMAHA SUPERJET Owners Manual

Care and storage
58
water flows out continually from the
cooling water pilot outlet.
(7) Run the engine at idling speed for about 3 minutes watching the engine condition.
If the engine stops while flushing, turn
the water supply off immediately and
perform the procedure again from step 6.
NOTICE: Do not supply water to the
cooling water passages when the en-
gine is not running. The water could
flow back through the muffler into the
engine, causing severe engine dam-
age.
[ECJ00123]
(8) Turn the water supply off.
(9) Discharge the remaining water out of the cooling water passages by alternately
squeezing and releasing the throttle lever
quickly for 10 to 15 seconds.
(10) Stop the engine.
(11) Remove the garden hose adapter, and then securely install the flushing hose
connector cap by tightening it until it
stops.
(12) Securely install the hood in its original position.
EJU40746Cleaning the watercraft
(1) Remove the hood. (See page 26 for hoodremoval and installation procedures.)
(2) If the watercraft will be stored for a week or more, rustproof the internal engine
components to help prevent corrosion. (See page 61 for information on rust-
proofing the internal engine compo-
nents.)
(3) Rinse the engine and engine compart- ment with a small amount of water.
NOTICE: Do not use high-pressure
water when rinsing the engine or en-
gine compartment as severe engine
damage could result.
[ECJ00572]
(4) Drain the water from the engine com- partment. (See page 35 for information
on draining the bilge water.)
(5) Wipe the engine and engine compart- ment with a dry cloth.
(6) Wash down the hull, deck, and jet pump with fresh water.
(7) Wipe the hull, deck, and jet pump with a dry cloth.
(8) Wipe all vinyl and rubber components, such as the engine compartment seals,
with a vinyl protectant.
(9) To minimize corrosion, spray metallic parts of the hull, deck, and engine with a
rust inhibitor.
(10) Allow the engine compartment to air dry completely before installing the hood.
(11) Securely install the hood in its original position.
EJU3368CBattery care
If the watercraft will not be used for more than
a month, remove the battery from the water-
craft, check it, and then store it in a cool, dry
place.
EWJ00793
Battery electrolyte is poisonous and dan-
gerous, causing severe burns, etc. Elec-
trolyte contains sulfuric acid. Avoid
contact with skin, eyes, or clothing.
Antidotes
External: Flush with water.
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Care and storage
59
Internal: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten
egg, or vegetable oil. Call a physician im-
mediately.
Eyes: Flush with water for 15 minutes and
get prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flames, cigarettes, etc., well away.
If using or charging the battery in an en-
closed space, make sure that it is well
ventilated. Always shield your eyes when
working near batteries.
Keep out of the reach of children.
To remove the battery:
(1) Disconnect the negative (–) battery lead.
(2) Disconnect the positive (+) battery lead.
(3) Unhook the battery bands, and then re-move the battery from the watercraft.
Checking the battery
Make sure that the battery case is not dam-
aged.
Make sure that the battery terminals are
not corroded or damaged.
Checking the battery voltage and charging
the battery
It is recommended to have a Yamaha dealer
check the battery voltage and charge the bat-
tery. Have a Yamaha dealer charge the bat- tery as soon as possible if it seems to have
discharged. Keep in mind that the battery
tends to discharge more quickly if the vehicle
is equipped with optional electrical accesso-
ries.
NOTICE: To charge a VRLA (Valve
Regulated Lead Acid) battery, a special
(constant-voltage) battery charger is re-
quired. Using a conventional battery char-
ger will damage the battery.
[ECJ02810]
Checking the battery bands
Make sure that the battery bands are not
damaged.
To store the battery:
(1) Clean the battery case using fresh water.
(2) If the battery terminals are dirty or cor- roded, clean them using a wire brush.
(3) Apply water-resistant grease to the bat- tery terminals.
1Positive (+) battery terminal: Red lead
2 Negative (–) battery terminal: Black lead
3 Battery band
1
2
3
1Battery band
1 Battery terminal
1
1
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Care and storage
60
(4) Store the battery in a cool, dry place.NOTICE: Storing the battery in an un-
charged condition can cause perma-
nent battery damage. Check the
battery periodically.
[ECJ00103]
To install the battery:
(1) Place the battery in the battery compart- ment and hook the battery bands onto
the holders.
(2) Connect the positive (+) battery lead (red) to the positive (+) battery terminal.
NOTICE: Reversal of the battery leads
will damage the electrical parts.
[ECJ00262]
(3) Connect the negative (–) battery lead (black) to the negative (–) battery termi-
nal.
(4) Make sure that the battery is securely held in place.
EJU33495
Long-term storageEWJ00332
Always place the watercraft upright in a
horizontal position when storing it, other-
wise fuel could leak out into the engine or
engine compartment, which could create
a fire hazard.
Storage for long periods of time, such as win-
ter storage, requires preventive maintenance
to ensure against deterioration. It is advisable
to have the watercraft serviced by a Yamaha
dealer prior to storage.
However, the following procedures can be
performed easily by the owner.
EJU40763Cleaning
(1) Flush the cooling water passages. (See
page 57 for information on flushing the
cooling water passages.)
TIP:
If you will be storing the watercraft for a pro-
longed period, such as winter storage, top off
the fuel tank with fresh gasoline and add fuel
stabilizer and conditioner to the fuel tank ac-
cording to the manufacturer’s instruction be-
fore starting the engine.
(2) Clean the watercraft. (See page 58 for in-formation on cleaning the watercraft.)
Wax the hull with a non-abrasive wax.
EJU45730Lubrication
Use a suitable marine grease applicator and
spray a rust inhibitor between the inner and
outer cables to lubricate the cables and
purge out any dirt and moisture.
To keep moving parts sliding or rotating
smoothly, lubricate them with water-resistant
grease.
Recommended water-resistant grease:
YAMALUBE MARINE
GREASE/Yamaha Grease A
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Care and storage
61
Throttle cable
Steering cable ball joint (handlebar end)
and steering cable inner wire (handlebar
end)
TIP:
Disconnect the steering cable (handlebar
end) from the ball joint before lubricating.
Steering cable (jet thrust nozzle end) and
ball joint
TIP:
Disconnect the steering cable from the ball
joint before lubricating.
EJU45861RustproofingECJ01361
Do not run the engine for more than 15
seconds on land without supplying water,
otherwise the engine could overheat.
Spray metallic parts of the hull and engine
with a rust inhibitor.
To rustproof the internal engine components:
(1) Remove the hood. (See page 26 for hoodremoval and installation procedures.)
(2) While loosening the clamp, remove the breather hose.
(3) Make sure that the area around the wa- tercraft is clear, and then start the engine
in a well-ventilated area.
(4) Run the engine at a fast idle.
(5) Quickly spray as much rust inhibitor as possible into the air intake duct through
the breather hose joint. Keep spraying
until the engine stalls (or a maximum of
15 seconds). WARNING! Do not pour or
spray gasoline, or any substance oth-
er than a rust inhibitor, into the air in-
take duct. Do not spray flammable
Recommended water-resistant grease:
YAMALUBE MARINE GREASE /
Ya m a h a G r e a s e A
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Care and storage
62
rust inhibitor products on engine sur-
faces while the engine is hot. Other-
wise, a fire or explosion could occur.
[EWJ02011]
(6) Install the breather hose, and fasten thebreather hose with the clamp.
(7) Securely install the hood in its original position.
1Breather hose
2 Clamp
3 Breather hose joint
4 Air intake duct
2
1
43
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Maintenance
63
EJU3376A
Maintenance
Periodic checks and lubrication will keep
your watercraft in the safest and most effi-
cient condition possible. Therefore, make
sure to carry out the periodic maintenance.
Safety is an obligation of the watercraft own-
er. Proper maintenance must be carried out
to keep the exhaust emission and sound lev-
els within the regulated limits. The most im-
portant points of watercraft inspection and
lubrication are explained on the following
pages.
See a Yamaha dealer for genuine Yamaha re-
placement parts and optional accessories
designed for your watercraft.
Remember, failures that are the result of the
installation of parts or accessories which are
not qualitatively equivalent to genuine
Yamaha parts are not covered by the limited warranty.
Maintenance, replacement, or repair of
the emission control devices and system
may be performed by any marine SI engine
repair establishment or individual. War-
ranty repair, however, must be performed
at an authorized Yamaha marine dealer-
ship.
EWJ00312
Be sure to turn off the engine when you
perform maintenance unless otherwise
specified. If you are not familiar with ma-
chine servicing, this work should be done
by a Yamaha dealer or other qualified me-
chanic.
EJU3433AAdjusting the steering friction
The amount of friction in the steering can be
adjusted to suit operator preference. To adjust the steering friction:
(1) Lift the steering pole and support it with
the lock pin.
(2) Remove the plastic fasteners, and then remove the handlebar cover.
(3) Turn the handlebars so that the left han- dlebar grip is facing down.
1Steering pole
1 Lock pin
1 Plastic fastener
2 Handlebar cover
1
1
12
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Maintenance
64
(4) Loosen the locknut.
(5) Tighten or loosen the adjusting nut untilthe desired amount of friction is ob-
tained.
(6) While holding the adjusting nut with a wrench, tighten the locknut to the speci-
fied torque.
(7) Securely install the handlebar cover and the plastic fasteners in their original posi-
tions.
(8) While holding the steering pole, move the lock pin to the stowed position, and
then lower the steering pole.
EJU3128CAdjusting the jet thrust nozzle angle
The angle of the jet thrust nozzle can be ad-
justed to two settings to suit operator prefer-
ence. To adjust the jet thrust nozzle angle:
(1) Pull back the outer sleeve of the steering
cable joint, and then disconnect the joint
from the steering cable pivot bolt.
(2) Remove the steering cable pivot bolt.
(3) Select the nozzle angle, install the steer- ing cable pivot bolt in the desired posi-
tion (P1 or P2) on the steering column,
and then tighten the bolt to the specified
torque.
1Adjusting nut
2 Locknut
Tightening torque:
Locknut:
28 N·m (2.8 kgf·m, 21 lb·ft)
1
2
1Steering cable joint
1 Steering cable pivot bolt
2 Steering column
1
2
1
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Maintenance
65
TIP:
The outermost hole in the steering column
cannot be used.
(4) Securely connect the steering cable jointto the steering cable pivot bolt.
EJU45671Adjusting the handlebar position
The handlebar can be adjusted to three posi-
tions to suit the rider’s preference. Have a Yamaha dealer adjust the position of the han-
dlebar.
1 Nozzle angles
1 Nozzle angles
2 Steering cable pivot bolt positions
Standard steering cable pivot bolt posi-
tion:
P2
Tightening torque:
Steering cable pivot bolt:5 N·m (0.5 kgf·m, 3.7 lb·ft)
11
1
16° P1
P2
19° 2
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