2008 YAMAHA SUPERJET spark plugs

Table of contents
Checking the jet thrust
nozzle angle ................................. 53
Adjusting the steering friction .......... 54
Adjusting the jet thrust
nozzle angle ................................. 55
Checking and
adjusting the throttle cable ........... 56
Cleaning and
adjusting the spark plugs ............. 57
Lubrication points ............................ 58
Adjusting the choke cable ............... 59
Checking the battery ....................... 60
Adjusting the carburetor .................. 61
Specifications .................................. 62
Specifications ................................ 62
Trouble recovery ............................. 63
Troubleshooting ........................... 63
Troubleshooting chart ...................... 63
Emergency procedures ................ 65
Cleaning the jet intake and
impeller ........................................ 65
Jumping the battery ......................... 66
Replacing the fuse ........................... 67
Towing the watercraft ...................... 67
Submerged watercraft ..................... 68
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Features and functions
16
1Fire extinguisher container
2Fuel cock knob
3Choke knob
4Clip
5Start switch
6Throttle lever
7Engine shut-off switch
8Engine stop switch
9Engine shut-off cord (lanyard)
10Bow
11Fuel tank
12Battery
13Silencer
14Spark plugs/Spark plug caps
15Muffler
16Water separator
17Fuel filter
18Flushing hose connector
19Electrical box
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Operation
26
to-oil ratio could result in fouled spark
plugs, smoky exhaust, and heavy car-
bon deposits.
Pour 2-stroke engine oil into a clean contain-
er, and then add gasoline. To mix them thor-
oughly, shake the container from side to side.
EJU31910Filling the fuel tank
CAUTION:
ECJ00290
Be careful when refueling. Avoid getting
water and other contaminants in the fuel
tank. Contaminated fuel can cause poor
running and engine damage.
(1) Lift the steering pole and support it with
the lock pin.
(2) Remove the hood. (See page 17 for hood
removal and installation procedures.)
(3) Remove the fuel tank filler cap, and then
slowly add the premixed fuel to the fueltank. Stop filling when the fuel level just
reaches the bottom of the filler tube.
(4) Install the fuel tank filler cap and the
hood.
NOTE:

The hood must be removed in order to view
the fuel level in the fuel tank while adding fu-
el.

Be careful not to spill fuel or overfill the fuel
tank.

Do not fill up the filler tube because fuel ex-
pands as it warms up and could overflow.
12-stroke engine oil
2Gasoline
Fuel-to-oil ratios (gasoline to oil)
Break-in period (first two tankfuls):
25 : 1
After break-in:
50 :1
Fuel tank capacity:
To t a l :
18 L (4.8 US gal) (4.0 Imp.gal)
Reserve:
5.5 L (1.5 US gal) (1.2 Imp.gal)
UF2F70E0.book Page 26 Tuesday, April 17, 2007 9:56 AM

Maintenance and care
51
EJU33820Periodic maintenance chart
The following chart gives general guidelines for periodic maintenance. However, maintenance
may need to be performed more frequently depending on your operating conditions.
This “” mark indicates maintenance that you may do yourself.
This “” mark indicates work to be done by a Yamaha dealer.
Item OperationInitial Thereafter every
Page 10
hours50
hours100
hours100
hours200
hours
6
months12
months12
months24
months
Spark plugsCheck, clean, adjust 57
Lubrication pointsLubricate 58
Intermediate hous-
ingLubricate 58
Fuel systemCheck 53
Fuel filterCheck, clean, replace 53
Fuel tankCheck, clean 53
CarburetorCheck, adjust 61
Trolling speedCheck, adjust 61
Carburetor throt-
tle shaftCheck—
Cooling water pas-
sagesFlush
*46
Bilge strainerClean—
ImpellerCheck—
Jet thrust nozzle
angleCheck, adjust 53
Handlebar pivot
shaftCheck—
Steering frictionCheck, adjust 54
Throttle cableCheck, adjust 56
Choke cableCheck, adjust 59
BatteryCheck, charge 60
Rubber couplingCheck—
Engine mountCheck—
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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)
UF2F70E0.book Page 57 Tuesday, April 17, 2007 9:56 AM

Trouble recovery
68

Tow the watercraft using the bow rope
hole only.

The bow must be kept up out of the wa-
ter during towing to prevent water from
entering the engine compartment.
EJU34730Submerged watercraft
If the watercraft is submerged or flooded with
water, follow the procedure below and consult
a Yamaha dealer as soon as possible. Failure
to do so could result in serious engine dam-
age!
In an emergency:
(1) Beach the watercraft and remove the
hood. Turn the watercraft over far enough
to drain the water from the engine com-
partment.
CAUTION:
ECJ00700
Turning the watercraft on its side with the
hood removed could cause damage to the
steering pole. Use two people to provide
enough support to make sure that the
steering pole is not damaged.
(2) Turn the watercraft upright again.
(3) Turn the fuel cock knob to “OFF”.
(4) Remove the spark plugs and dry them
with a cloth.(5) Without reinstalling the spark plugs,
crank the engine until all of the water in
the cylinders has been drained.
(6) Install the spark plugs and the hood.
(7) Turn the fuel cock knob to “ON”.
(8) Launch the watercraft into the water, and
then run the engine for at least 10 min-
utes. If the engine does not start, repeat
steps 3–8.
(9) Shut the engine off.
(10) Turn the fuel cock knob to “OFF”, remove
the silencer cap, and then spray a rust in-
hibitor into the carburetor while cranking
the engine.
(11) Have the watercraft inspected by a
Yamaha dealer as soon as possible.
1Bow rope hole
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Index
R
Recommended equipment ....................... 11
Rough water operation ............................. 43
S
Safe boating rules .................................... 13
Spark plugs, cleaning and adjusting ........ 57
Standing ................................................... 37
Start switch............................................... 20
Starting the engine ................................... 33
Starting the watercraft .............................. 38
Steering friction, adjusting ........................ 54
Steering pole ...................................... 22, 31
Steering system ................................. 21, 30
Stern rope hole......................................... 22
Stopping the engine ................................. 35
Stopping the watercraft ............................ 42
Storage..................................................... 46
Storage pouch .......................................... 23
Submerged watercraft .............................. 68
Switches ................................................... 32
T
Throttle cable, checking and adjusting ..... 56
Throttle lever ...................................... 20, 30
Towing the watercraft ............................... 67
Transporting ............................................. 44
Trolling speed, adjusting .......................... 61
Troubleshooting ....................................... 63
Troubleshooting chart .............................. 63
Turning the watercraft .............................. 41
W
Water separator ....................................... 28
Watercraft characteristics......................... 12
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