YAMAHA SUPERJET 2008 Repair Manual

Maintenance and care
54
Turn the handlebars as far as possible to the
right and left and check that the difference of
distances A and B between the jet thrust noz-
zle and the nozzle is within specification.
If the steering is stiff or misadjusted, have a
Yamaha dealer service it.
EJU34331Adjusting 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 four screws, and then re-
move the handlebar cover.
(3) Turn the handlebars so that the left han-
dlebar grip is facing down. Difference of A and B:
Maximum 5 mm (0.20 in)
1Steering pole
2Lock pin
1Adjusting nut
2Locknut
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Maintenance and care
55
(4) Loosen the locknut.
(5) Tighten or loosen the adjusting nut until
the desired amount of friction is obtained.
(6) Hold the adjusting nut with one wrench
while tightening the locknut with another
wrench.
(7) Install the handlebar cover and the four
screws.
EJU31282Adjusting the jet thrust nozzle angle
The angle of the jet thrust nozzle can be ad-
justed to suit operator preference according to
the following procedure.
To change the steering cable pivot bolt posi-
tion:
(1) Remove the two screws, and then re-
move 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.
(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 Tightening torque:
29.0 Nm (21.4 ft-lb) (2.96 kgf-m)
1Steering pole cover
1Steering cable joint
1Steering cable pivot bolt
2Steering column
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Maintenance and care
56
steering column, and then tighten it to the
specified torque.
NOTE:
Do not install the steering cable pivot bolt in
the outermost hole in the steering column.
(5) Connect the steering cable joint to the
steering cable pivot bolt.(6) Install the steering pole cover, and then
install the two screws.
EJU34361Checking and adjusting the throttle
cable
Check that the throttle cable moves back to
the set position smoothly and that the throttle
lever free play is within specification.
Squeeze and release the throttle lever. If the
throttle lever does not return smoothly, have a
Yamaha dealer service it.
If the specified throttle lever free play cannot
be obtained as described below, have a
Yamaha dealer make the adjustment.
(1) Remove the four screws, and then re-
move the handlebar cover.
(2) Loosen the locknut.
(3) Adjust the free play by turning the adjust-
er.
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 Nm (4.0 ft-lb) (0.55 kgf-m)
1Locknut
2Adjuster
3Throttle lever free play
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Maintenance and care
57
(4) Hold the adjuster with one wrench while
tightening the locknut with another
wrench.
(5) Install the handlebar cover and the four
screws.
EJU34371Cleaning and adjusting the spark
plugs
WARNING
EWJ00350
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.
The spark plug is an important engine compo-
nent and is easy to inspect. The condition of
the spark plug can indicate something 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 di-
agnose any problems yourself. Have a
Yamaha dealer service the watercraft.
Remove and inspect the spark plugs periodi-
cally; heat and deposits will cause the spark
plugs to slowly break down and erode. If elec-
trode erosion becomes excessive, or if carbon
and other deposits are excessive, replace the
spark plug with the specified plug.Measure the spark plug gap with a wire thick-
ness gauge. Replace the spark plugs or ad-
just the gap to specification if necessary.
To install a 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.
NOTE:

Wipe off any water on the spark plug or in-
side the spark plug cap before installing the
cap. Push the spark plug cap down until it is
securely installed.

If a torque wrench is not available when you
are installing a spark plug, a good estimate
of the correct torque is 1/4 turn to 1/2 turn
past finger tight using the spark plug
wrench included in the tool kit. Have the
spark plug adjusted to the correct torque
with a torque wrench as soon as possible.
Throttle lever free play:
7.0–10.0 mm (0.28–0.39 in)
Specified spark plug:
BR7HS
1Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Spark plug tightening torque:
25.0 Nm (18.4 ft-lb) (2.55 kgf-m)
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Maintenance and care
58
EJU34400Lubrication points
To keep moving parts sliding or rotating
smoothly, coat them with water-resistant
grease.

Throttle cable (carburetor end)

Choke cable (carburetor end)

Throttle cable (handlebar end)
Squeeze the throttle lever and remove the
seal. Spray a rust inhibitor into the outer ca-
ble. Refit the seal securely.

Steering cable ball joint (handlebar end)

Steering cable inner wire (handlebar end)
(1) To access the steering cable and ball
joint, remove the steering pad by re-
moving the two bolts.(2) Grease the steering cable ball joints,
both at the handlebar end of the cable
and at the jet thrust nozzle end.
(3) Extend the steering cable inner wire,
and then apply a thin coat of grease to
the inner wire, both at the handlebar
end of the cable and at the jet thrust
nozzle end.

Steering cable ball joint (jet thrust nozzle
end)

Steering cable inner wire (jet thrust nozzle
end)

Handlebar pivot shaft
Lubrication of the handlebar pivot shaft re-
quires disassembly of steering compo- Recommended water-resistant grease:
Yamaha Marine Grease/Yamaha
Grease A
1Seal
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Maintenance and care
59
nents. Have a Yamaha dealer lubricate the
handlebar pivot shaft.

Jet thrust nozzle pivot bolts (collars)

Intermediate housing
Fill the intermediate housing with water-re-
sistant grease through the grease nipple
using a grease gun.
EJU34440Adjusting the choke cable
Check that the choke cable is properly adjust-
ed.
(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.
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)
1Choke knob adjusting nut
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Maintenance and care
60
EJU34451Checking the battery
Check the level of the battery electrolyte and
make sure that the negative (–) and positive
(+) battery leads are tightened securely.
WARNING
EWJ00790
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.
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 ven-
tilated. Always shield your eyes when
working near batteries.
KEEP OUT OF THE REACH OF CHILDREN.
CAUTION:
ECJ00230

Be careful not to place the battery on its
side.

Be sure to remove the battery from the
battery compartment when adding elec-
trolyte or charging the battery.
To remove the battery:
Disconnect the negative (–) battery lead first,
then the positive (+) battery lead and breather
hose, and then remove the battery from the
watercraft.To replenish the battery:
(1) Make sure that the electrolyte level is be-
tween the maximum and minimum level
marks.
(2) If the electrolyte level is low, add distilled
water to raise it to the specified level.
CAUTION:
ECJ00240
Normal tap water contains minerals that
are harmful to a battery. Use only distilled
water for replenishing the battery.
To recharge the battery:
CAUTION:
ECJ00250
Do not attempt to charge a battery hastily.
Battery life could be shortened.
It is recommended to have a Yamaha dealer
charge the battery. If you charge the battery
yourself, be sure to read and follow the in-
structions provided with the battery tester and
charger you use.
To install the battery:
(1) Place the battery in the battery compart-
ment and connect the battery leads to the
battery terminals.
(2) Connect the breather hose to the battery.
1Maximum level mark
2Minimum level mark
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Maintenance and care
61
(3) Secure the battery in place.
WARNING
EWJ00400
Be sure to connect the breather hose to
the battery. Fire or explosion could result
if the breather hose is damaged, obstruct-
ed, or not connected properly.
CAUTION:
ECJ00260
After installation, make sure that the bat-
tery leads are properly connected to the
battery terminals.
EJU34460Adjusting the carburetor
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 trolling speed as part
of the usual maintenance routine.
CAUTION:
ECJ00170
The carburetor was set at the Yamaha fac-
tory after many tests. If the settings are
disturbed by someone who does not have
the necessary technical knowledge, poorengine performance and damage may re-
sult.
EJU34470Adjusting the trolling 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 en-
gine speed to specification. Turn the
throttle stop screw clockwise to increase
the engine speed or counterclockwise to
decrease the engine speed.
1Positive (+) battery terminal: Red lead
2Negative (–) battery terminal: Black lead
3Breather hose
1Throttle stop screw
Trolling speed:
1300 ±50 r/min
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Specifications
62
EJU34542
Specifications
Watercraft capacity:
Maximum people on board:
1 person
Dimensions:
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 output (according to ISO 8665/SAE
J1228):
48.50 kW@6250 r/min
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:
BR7HS
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Battery capacity:
12 V, 19.0 AhCharging 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
63
EJU34560
Troubleshooting
If you have any trouble with your watercraft, use this section to check for the possible cause.
If you cannot find the cause, or if the procedure for replacement or repair is not described in
this owner’s/operator’s manual, have a Yamaha dealer perform the necessary service.
EJU34570Troubleshooting 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 60
Poor terminal con-
nectionsTighten as required
60
Terminal corroded Clean 48
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”18
Fuel Empty Refill as soon as pos-
sible26
Stale or contaminat-
edHave serviced by
Yamaha dealer53
Fuel tank Water or dirt present Have serviced by
Yamaha dealer53
Spark plug Fouled or defective Clean or replace 57
Spark plug
capNot connected or
looseConnect properly
57
Crankcase Filled with water Crank engine with
plug out until clean68
Fuel filter Clogged or water
pooledHave serviced by
Yamaha dealer53
Choke Knob moves back on
its ownTighten choke knob
adjusting nut59
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