engine YAMAHA SUPERJET 2001 Workshop Manual

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Adjusting the carburetor
The carburetor is a vital part of the engine
and requires very sophisticated adjustment.
Most adjusting should be left to a Yamaha
dealer who has the professional knowledge
and experience to perform it. However, the
operator may adjust the trolling speed as
part of the usual maintenance routine.
CAUTION:@The carburetor was set at the Yamaha
factory after many tests. If the settings
are disturbed by someone who does not
have the necessary technical knowledge,
poor engine performance and damage
may result.
@
EJU00574a
Adjusting the trolling speed
1. Put the watercraft in the water.
2. Start the engine and warm it up for 1 or
2 minutes. Using a diagnostic tachome-
ter, adjust the engine speed to specifica-
tion.
3. Turn the throttle stop screw 1 clockwise
to increase engine speed if necessary.
Turn it counterclockwise to decrease
engine speed if necessary.
Trolling speed: 1,250–1,350 r/min
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Specifications
*1: Pump Octane Number
*1: Research Octane NumberMODEL
ITEMUnit SJ700
WATERCRAFT CAPACITY
Maximum people on board Number of people 1
DIMENSIONS
Length mm (in) 2,240 (88.2)
Width mm (in) 680 (26.8)
Height mm (in) 660 (26.0)
Dry weight kg (lb) 132 (291)
PERFORMANCE
Maximum power output kW (PS) @ r/min 53.6 (73) @ 6,300
Maximum fuel consumption L/h (US gal/h, Imp gal/h) 29 (7.7, 6.4)
Cruising range at full throttle hr. 0.6
Trolling speed r/min 1,250–1,350
ENGINE
Engine type 2-stroke
Number of cylinders 2
Engine displacement
cm
3 (cu in)701 (42.78)
Bore & stroke mm (in) 81 ×
68 (3.19 ×
2.68)
Compression ratio 7.2
Lubrication system Pre-mixed fuel
Cooling system Water cooled
Starting system Electric starter
Ignition system CDI
Spark plug BR-7HS (NGK)
Spark plug gap mm (in) 0.6–0.7 (0.024–0.028)
Battery capacity V-AH 12-19
Charging system Flywheel magneto
DRIVE UNIT
Propulsion system Jet pump
Jet pump type Mixed flow, single stage
Impeller rotation Counterclockwise (viewed from rear)
Transmission Direct drive from engine
Jet thrust nozzle angle Degree 37, 41, 45, 49
FUEL AND OIL
Recommended fuel Regular unleaded gasoline
Minimum octane rating PON (*1)
RON (*1)86
90
Recommended engine oil YAMALUBE 2-W, or an equivalent NMMA-
certified TC-W3 marine oil
Fuel mixing ratio (fuel to oil) 50:1
Fuel tank capacity
Total L (US gal, Imp gal) 18 (4.8, 4.0)
Reserve L (US gal, Imp gal) 5.5 (1.45, 1.21)
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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.
EJU00596
Troubleshooting chart
TROUBLE POSSIBLE CAUSE REMEDY PAGE
Engine does not
startStarter motor does not turn over
Engine shut-
off switch Clip not in place Install clip
2-5
Fuse Burned out Replace fuse and check
wiring4-20
Battery Run down Recharge 4-18
Poor terminal connec-
tionsTighten as required
4-18
Starter motor Faulty Have serviced by
Yamaha dealer—
Starter motor turns over
Fuel cock Turned to “OFF” Turn fuel cock knob to
“ON”2-4
Fuel Empty Refill as soon as possi-
ble3-4
Stale or contaminated Have serviced by
Yamaha dealer4-10
Fuel tank Water or dirt present Have serviced by
Yamaha dealer4-11
Spark plug Fouled or defective Clean or replace 4-13
Spark plug cap Not connected or loose Connect properly 4-13
Crankcase Filled with water Crank engine with plug
out until clean5-7
Fuel filter Clogged or water
pooledHave serviced by
Yamaha dealer4-11
Choke Knob moves back on
its ownTighten choke knob
adjusting nut4-16
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Engine runs irregu-
larly or stallsFuel Empty Refill as soon as possi-
ble3-4
Stale or contaminated Have serviced by
Yamaha dealer4-10
Too much oil in fuel
mixing ratioCorrect fuel-to-oil ratio
to 50:13-3
Choke Knob is left pulled Push fully in 2-6
Fuel filter Clogged or water
pooledHave serviced by
Yamaha dealer4-11
Fuel tank Water or dirt present Have serviced by
Yamaha dealer4-11
Spark plug Fouled or defective Replace 4-13
Incorrect heat range Replace 4-13
Gap incorrect Adjust 4-13
Spark plug cap Loose Connect properly 4-13
Cracked, torn or dam-
agedReplace
4-13
Electrical wir-
ingLoose electrical con-
nectionsTighten or connect
properly—
Carburetor Incorrect idle adjust-
mentAdjust idle
4-19
Clogged Have serviced by
Yamaha dealer4-19
Wate rcr af t slow or
loses powerCavitation Jet intake clogged Clean 5-3
Impeller damaged or
wornHave serviced by
Yamaha dealer5-3
Engine over-
heatedJet intake clogged Clean
5-3
Fuel filter Clogged Have serviced by
Yamaha dealer4-11
Spark plug Fouled or defective Replace 4-13
Incorrect heat range Replace 4-13
Gap incorrect Adjust 4-13
Spark plug
capsLoose Connect properly
4-13
Fuel Stale or contaminated Have serviced by
Yamaha dealer4-10 TROUBLE POSSIBLE CAUSE REMEDY PAGE
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Emergency procedures
Cleaning the jet intake and
impeller
If weeds or debris get caught in the intake
or impeller, cavitation can occur, causing jet
thrust to decrease even though engine
speed rises. If this condition is allowed to
continue, the engine will overheat and may
seize. If there is any sign that the jet intake
or impeller is clogged with weeds or debris,
beach the watercraft and check the intake
and impeller. Always stop the engine before
beaching the watercraft.
WARNING@Before attempting to remove weeds or
debris from the jet intake or impeller
areas, shut the engine off and remove
the clip from the engine shut-off switch.
Severe injury or death could result from
coming in contact with the rotating parts
of the jet pump.
@
1. Turn the watercraft on its side as shown.
CAUTION:@●Place a suitable clean cloth or carpet-
ing underneath the watercraft to pro-
tect it from abrasions and scratches.
●Always turn the watercraft over onto
its port (left) side.
●When turning the watercraft on its
side, support the bow and secure the
steering pole, otherwise the steering
pole and handlebars could be bent or
damaged.
@
2. Remove any weeds or debris from
around the drive shaft, impeller, and jet
thrust nozzle.
If debris is difficult to remove, consult
your Yamaha dealer.
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CAUTION:@Always avoid operating your watercraft in
areas where weed growth is thick. If trav-
eling in weeded areas is unavoidable,
operate the engine alternately at partial
throttle and full throttle. Weeds tend to
accumulate more at a steady speed and
at trolling speed. If weeds clog the intake
or impeller area and cause cavitation, fol-
low the cleaning procedure above.
@
EJU00599
Jumping the battery
If the watercraft battery has run down, the
engine can be started using a 12-volt bat-
tery and jumper cables.
WARNING@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 physi-
cian immediately.
Eyes: Flush with water for 15 minutes
and get prompt medical attention
Batteries give off explosive gases. Keep
sparks, flame, cigarettes, etc. well away.
If using or charging the battery in an
enclosed area, make sure that it is well
ventilated. Always shield your eyes when
working near batteries.
KEEP OUT OF THE REACH OF CHIL-
DREN
@
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Connecting the jumper cables
1. Connect the positive (+) jumper cable 2
to the positive (+) terminals of both bat-
teries.
2. Connect one end of the negative (–)
jumper cable 1 to the negative (–) termi-
nal of the booster battery 3.
3. Connect the other end of the negative (–)
cable to an unpainted bolt on the cylinder
head.
CAUTION:@Do not connect the end of the jumper
cable to the negative (–) terminal on the
watercraft battery! Make sure all connec-
tions are secure and correct before
attempting to start the engine. Any
wrong connection may damage the elec-
trical system.
@
4. Start the engine, and then disconnect
the cables by reversing the steps above.
CAUTION:@●Never push the start switch while the
engine is running.
●Do not operate the start switch for
more than 5 seconds, otherwise the
battery will be discharged and the
engine will not start. Also, the starter
motor may be damaged. If the engine
does not start in 5 seconds, release
the start switch, wait 15 seconds, and
try again.
@
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Towing the watercraft
If the watercraft becomes inoperative in
the water, it can be towed to shore.
If the watercraft must be towed in an
emergency using a tow line, the operator
should ride the watercraft, holding onto the
handlebars and supporting his body weight
on the riding tray. This will help keep the bow
of the watercraft out of the water.
CAUTION:@●Tow the watercraft slowly; water may
enter the air intake and flood the
engine compartment if the watercraft
is towed too fast.
●Tow the watercraft using the rope hole 1
only.
●The bow must be kept up out of the
water during towing to prevent water
from entering the engine compart-
ment.
@
WARNING@●The watercraft should only be towed in
an emergency.
●The tow line should be long enough so
that the watercraft will not collide with
the towing boat when slowing down. A
good rule of thumb is a tow line which
is three times the combined length of
the towing boat and the watercraft. A
shorter length of rope can be used if
the watercraft is towed very slowly.
●The operator of the towing boat must
keep speed to a minimum and avoid
traffic or obstacles which could be a
hazard to the operator on the water-
craft.
@
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Submerged watercraft
If the watercraft is submerged or flooded
with water, follow the procedure below and
consult a Yamaha dealer as soon as possi-
ble. Failure to do so may result in serious
engine damage!
1. Beach the watercraft and remove the
hood. Turn the watercraft over far
enough to drain the water from the
engine compartment. Make sure all
water is thoroughly drained.
CAUTION:@Turning the watercraft on its side with the
hood removed could cause damage to
the steering pole. Use two people to pro-
vide 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 water in the cyl-
inders has been drained.
6. Install the spark plugs.
7. Turn the fuel cock knob to “ON.”
8. Launch the watercraft into the water, and
then run the engine for at least
10 minutes. If engine will not start,
repeat steps above.
9. Turn the engine off. Turn the fuel cock
knob to “OFF.”
10. Remove the silencer cap and spray a
rust inhibitor into the carburetor while
cranking the engine.
11. Have the watercraft inspected by a
Yamaha Dealer as soon as possible.
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Index
2-stroke engine oil ................................... 3-2
A
Adjusting the carburetor ........................ 4-19
Adjusting the choke cable ..................... 4-16
Adjusting the jet thrust nozzle angle ..... 4-21
Adjusting the steering friction ................ 4-20
Adjusting the trolling speed ................... 4-19
Approval label of Emission control
certificate ................................................. 1-2
B
Battery .............................................. 3-8, 4-5
Beaching the watercraft ........................ 3-30
Bilge ........................................................ 3-7
Boarding and starting in deep water ..... 3-22
Boarding and starting in shallow
water ..................................................... 3-24
C
Capsized watercraft .............................. 3-26
Caution label ........................................... 1-7
Choke knob ............................................. 2-6
Cleaning and adjusting the spark
plugs...................................................... 4-13
Cleaning the jet intake and impeller ........ 5-3
Cleaning the watercraft ........................... 4-6
Connecting the jumper cables................. 5-5
Cooling water pilot outlet ................ 2-7, 3-12
Cruising limitations .................................. 1-9
E
Emergency procedures ........................... 5-3
Emission control information ................... 1-2
Engine break-in ..................................... 3-13
Engine compartment ............................... 3-6
Engine overheat warning system ............ 2-9
Engine serial number .............................. 1-1
Engine shut-off cord (lanyard) ............... 3-11
Engine shut-off switch ............................. 2-5
Engine stop switch .................................. 2-5
Enjoy your watercraft responsibly ......... 1-14
F
Filling the fuel tank .................................. 3-4Fire extinguisher ...................................... 3-9
Flushing the cooling system .................... 4-1
Fuel and oil.............................................. 3-1
Fuel cock knob ........................................ 2-4
Fuel filter ............................................... 4-11
Fuel system ......................................3-6, 4-5
Fuel tank ............................................... 4-11
Fuel tank filler cap ................................... 2-4
G
Gasohol ................................................... 3-2
Gasoline .................................................. 3-1
Getting to know your watercraft ............ 3-19
H
Hazard information ................................ 1-12
Hood........................................................ 2-3
Hull Identification Number (HIN).............. 1-1
I
Identification numbers ............................. 1-1
Important labels ....................................... 1-3
Inspecting and adjusting the throttle
cable...................................................... 4-12
Inspecting the battery ............................ 4-17
Inspecting the fuel system ..................... 4-10
Inspecting the steering cable................ 4-12
J
Jet unit................................................... 3-11
Jumping the battery ................................. 5-4
K
Kneeling ................................................ 3-25
L
Label location .......................................... 1-3
Learning to operate your watercraft ...... 3-19
Leaving the watercraft ........................... 3-18
Limitations on who may operate the
watercraft ................................................ 1-8
Location of main components ................. 2-1
Lubrication............................................... 4-3
Lubrication points .................................. 4-14
M
Maintenance and adjustments ................ 4-7
Mixing fuel and oil ................................... 3-3
O
Operating positions ............................... 3-25
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