YAMAHA SUPERJET 2018 Repair Manual

Care and storage
55
Steering cable ball joint (handlebar end)
and steering cable inner wire (handlebar
end)
To access the steering cable ball joint (han-
dlebar end) and steering cable inner wire
(handlebar end), remove the steering pole
cover. (See step 1 in “Adjusting the jet
thrust nozzle angle” on page 57 for infor-
mation on removing the steering pole cov-
er.)
Steering cable ball joint (jet thrust nozzle
end) and steering cable inner wire (jet
thrust nozzle end)
EJU40944Rustproofing
NOTICE
ECJ01361
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 23 for hood
removal and installation procedures.)
(2) Loosen the silencer cap and remove it.
(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 through the hole in the silencer
cover. Keep spraying until the engine
stalls (or a maximum of 15 seconds).
WARNING! Do not pour or spray gaso-
line, or any substance other than a
rust inhibitor through the hole in the
silencer cover. Do not spray flamma-
ble rust inhibitor products on engine
surfaces while the engine is hot. Oth-
erwise, a fire or explosion could oc-
cur.
[EWJ00302]
(6) Securely install the silencer cap by tight-
ening it until it stops. NOTICE: Be sure
to install the silencer cap securely af-
ter fogging the engine, otherwise wa-
ter could enter the engine and cause
damage.
[ECJ00153]
(7) Securely install the hood in its original
position.
1Silencer cap
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Maintenance
56
EJU33769
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 pa-
ges.
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.
WARNING
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.
EJU33803Tool kit
A tool kit is included with this watercraft. Pla-
ce the tool kit in a waterproof bag and alwayscarry it with you whenever you use the water-
craft.
EJU34337Adjusting 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.
1Tool bag
2Screwdriver
310/12 mm box wrench
4Garden hose adapter
5Spark plug (one included for each cylinder)
614/21 mm box wrench
7Pliers
810/12 mm open-end wrench
1Steering pole
2Lock pin
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Maintenance
57
(2) Remove the four screws, and then re-
move the handlebar cover.
(3) Turn the handlebars so that the left han-
dlebar grip is facing down.
(4) Loosen the locknut.
(5) Tighten or loosen the adjusting nut until
the 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
four screws in their original positions.(8) While holding the steering pole, move
the lock pin to the stowed position, and
then lower the steering pole.
EJU31289Adjusting 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) Remove the two bolts, and then remove
the steering pole cover.
(2) Pull back the outer sleeve of the steering
cable joint, and then disconnect the joint
from the steering cable pivot bolt.
1Handlebar cover
1Adjusting nut
2Locknut
Tightening torque:
Locknut:
29.0 N·m (2.96 kgf·m, 21.4 lb·ft)
1
1Steering pole cover
1Steering cable joint
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Maintenance
58
(3) Remove the steering cable pivot bolt.
(4) Select the nozzle angle, install the steer-
ing cable pivot bolt with the lock washer
in the desired position (P1 or P2) on the
steering column, and then tighten the
bolt to the specified torque.TIP:
The outermost hole in the steering column
cannot be used.
(5) Securely connect the steering cable joint
to the steering cable pivot bolt.
(6) Securely install the steering pole cover
and two bolts in their original positions.
1Steering cable pivot bolt
2Steering column
1Nozzle angles
1Nozzle angles
2Steering cable pivot bolt positions
Standard steering cable pivot bolt posi-
tion:
P2
Tightening torque:
Steering cable pivot bolt:
5.4 N·m (0.55 kgf·m, 4.0 lb·ft)
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Maintenance
59
EJU40831Periodic maintenance chart
The periodic maintenance chart gives general guidelines for periodic maintenance. Have a
Yamaha dealer perform the checks in the following chart. However, maintenance may need
to be performed more frequently depending on your operating conditions. If you have any
questions, consult a Yamaha dealer.
This “ ” mark indicates maintenance that you may do yourself.
This “ ” mark indicates items to be checked and serviced by a Yamaha dealer.
Item OperationInitial Thereafter every
Page 10
hours50 hours100
hours200
hours
6
months12
months12
months24
months
Spark plugsCheck, clean, replace 60
Lubrication pointsLubricate 54
Intermediate
housingLubricate 61
Fuel systemCheck —
Fuel filterCheck 61
Check, replace —
Fuel tankCheck, clean —
CarburetorCheck, adjust —
Engine idling
speedCheck, adjust 62
Carburetor throttle
shaftCheck —
Bilge strainerClean —
ImpellerCheck —
Jet thrust nozzle
angleCheck, adjust —
Handlebar pivot
shaftCheck, adjust —
Steering frictionCheck, adjust —
Steering masterCheck, adjust —
Throttle cableCheck, adjust —
Choke cableCheck, adjust 61
BatteryCheck, charge —
Rubber couplingCheck —
Engine mountCheck —
Nuts and boltsCheck —
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Maintenance
60
EJU3437AChecking the spark plugs
WARNING
EWJ00351
Be careful not to damage the insulator
when removing or installing a spark plug.
A damaged insulator could allow sparks to
escape, which could result in a fire or ex-
plosion.
Remove and check the condition of the spark
plugs.
The condition of a spark plug can indicate
something about the condition of the engine.
For example, if the center electrode portion 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.
To remove a spark plug:
(1) Remove the hood. (See page 23 for hood
removal and installation procedures.)
(2) Remove the spark plug cap.
(3) Remove the spark plug, and then check
the condition of the spark plug and the
spark plug gap. If the electrode portion is
significantly discolored, if electrode ero-
sion becomes excessive, if carbon and
other deposits are excessive, or if the
spark plug gap is not within the specified
range, replace the spark plug.
TIP:
When the engine is operating normally, the
color of the spark plug electrode portion will
be a medium-to-light tan.
To install a spark plug:
(1) Wipe off any dirt from the threads, insu-
lator, and gasket surface of the spark
plug.
(2) Install the spark plug, and then tighten it
to the specified torque.
TIP:
If a torque-wrench is not available when you
are reinstalling a spark plug, a good estimate
of the correct torque is 1/12 turn past finger-
tight. When you are installing a new spark
plug, a good estimate of the correct torque is
1/2 to 2/3 turn past finger-tight.
(3) Wipe off any water or dirt inside the
spark plug cap.
1Insulator
2Electrode
3Spark plug gap
Specified spark plug:
BR7HS
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
25.0 N·m (2.55 kgf·m, 18.4 lb·ft)
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Maintenance
61
(4) Install the spark plug cap by pushing it
down until it is securely installed in its
original position.
(5) Securely install the hood in its original
position.
EJU41182Lubrication points
Lubricate moving parts with water-resistant
grease. (See page 54 for information on the
main lubrication points.)
Intermediate housing
Fill the intermediate housing with water-resis-
tant grease through the grease nipple using a
grease gun.
EJU34226Checking the fuel filter
Check the fuel filter. The fuel filter should be
replaced if water or dirt is found in the filter.Have a Yamaha dealer replace the fuel filter if
necessary.
EJU34442Adjusting the choke cable
Check that the choke cable is properly ad-
justed.
To adjust the choke cable:
(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
nut slightly. If the knob is difficult to
move, loosen the adjusting nut slightly.
EJU34464Adjusting the carburetor
NOTICE
ECJ00173
If the carburetor settings are disturbed by
someone who does not have the neces- Recommended water-resistant grease:
YAMALUBE MARINE
GREASE/Yamaha Grease A
Grease quantity:
Initial 10 hours or 1 month:
20.0–22.0 cm³ (0.68–0.74 US oz,
0.71–0.78 Imp.oz)
Every 100 hours or 12 months:
3.0–5.0 cm³ (0.10–0.17 US oz,
0.11–0.18 Imp.oz)
1Fuel filter
1Choke knob adjusting nut
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Maintenance
62
sary technical knowledge, poor engine
performance and damage may result.
The carburetor is a vital part of the engine and
requires very sophisticated adjustments.
Most adjustments should be left to a Yamaha
dealer who has the professional knowledge
and experience to make them.
However, the operator may adjust the engine
idling speed as part of the usual maintenance
routine.
EJU34472Adjusting the engine idling speed
(1) Place the watercraft in the water.
(2) Start the engine and warm it up for 1 to 2
minutes.
(3) While using a diagnostic tachometer,
turn the throttle stop screw to adjust the
engine idling speed to specification. Turn
the throttle stop screw clockwise to in-
crease the engine idling speed or coun-
terclockwise to decrease the engine
idling speed.
1Throttle stop screw
Engine idling speed:
1300 ±50 r/min
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Specifications
63
EJU34543
Specifications
Watercraft capacity:
Maximum people on board:
1 person
Dimensions and weight:
Length:
2240 mm (88.2 in)
Width:
680 mm (26.8 in)
Height:
660 mm (26.0 in)
Dry weight:
139 kg (306 lb)
Performance:
Maximum fuel consumption:
29.0 L/h (7.7 US gal/h, 6.4 Imp.gal/h)
Cruising range at full throttle:
0.62 hour
Trolling speed:
1300 ±50 r/min
Engine:
Engine type:
2-stroke
Number of cylinders:
2
Engine displacement:
701 cm³
Bore × stroke:
81.0 × 68.0 mm (3.19 × 2.68 in)
Compression ratio:
7.2 : 1
Lubrication system:
Pre-mixed fuel and oil
Cooling system:
Water
Starting system:
Electric
Ignition system:
C.D.I.
Spark plug (NGK):
BR7HS
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Battery capacity:
12 V, 19 Ah
Charging system:
Flywheel magneto
Drive unit:
Propulsion system:
Jet pump
Jet pump type:
Axial flow, single stage
Impeller rotation:
Counterclockwise
Jet thrust nozzle angle:
P1: 14.4+14.4°
P2: 17.3+17.3°
Fuel and oil:
Recommended fuel:
Regular unleaded gasoline
Minimum octane rating (PON):
86
Minimum octane rating (RON):
90
Recommended engine oil:
YAMALUBE 2-W or TC-W3 outboard motor
oil or equivalent
Fuel mixing ratio (fuel to oil):
50 : 1
Fuel tank total capacity:
18 L (4.8 US gal, 4.0 Imp.gal)
Fuel tank reserve capacity:
5.5 L (1.5 US gal, 1.2 Imp.gal)
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Trouble recovery
64
EJU34562
Troubleshooting
If you have any trouble with your watercraft, use the troubleshooting chart to check for the
possible cause.
If you cannot find the cause, consult a Yamaha dealer.
EJU34576Troubleshooting chart
TROUBLE POSSIBLE CAUSE REMEDY PAGE
Engine does not
start (Starter motor
does not turn over)Engine shut-
off switchClip not in place Install clip
19
Fuse Burned out Replace fuse and
check wiring67
Battery Run down Recharge 51
Poor terminal con-
nectionsTighten as required
51
Terminal corroded Clean or replace 51
Starter motor Faulty Have serviced by
Yamaha dealer—
Engine does not
start (Starter motor
turns over)Fuel cock Turned to “OFF” Turn fuel cock knob
to “ON”21
Fuel Empty Refill as soon as pos-
sible28
Stale or contaminat-
edHave serviced by
Yamaha dealer—
Fuel tank Water or dirt present Have serviced by
Yamaha dealer—
Spark plug Fouled or defective Replace 60
Spark plug
capNot connected or
looseConnect properly
60
Crankcase Filled with water Have serviced by
Yamaha dealer69
Fuel filter Clogged or water
pooledHave serviced by
Yamaha dealer61
Choke Knob moves back on
its ownTighten choke knob
adjusting nut61
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