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4-17
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Measure the spark plug gap a with a
wire thickness gauge. Replace the spark
plug or adjust the gap to specification if nec-
essary.
To install the 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
inside the cap before installing the spark
plug cap. Push the spark plug cap down
until it is securely installed.
If a torque wrench is not available when
you are installing a new spark plug, a good
estimate of the correct torque is 1/4 turn to
1/2 turn past finger tight with 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.
@
WARNING@ Be careful not to damage the insulator
when removing or installing a spark plug.
A damaged insulator could allow sparks
to escape, which could lead to an explo-
sion or fire.
@
5. Install the air filter element in the air filter
case, and then install the air filter case
cover. Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Spark plug tightening torque:
12.5 N·m (1.25 kgf·m, 9 ft·lb)
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4-21
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EJU19710
Inspecting the battery
Check the level of the battery electrolyte
and make sure that the negative and posi-
tive leads are securely tightened.
WARNING@ Battery electrolyte is poisonous and
dangerous, causing severe burns, etc.
Electrolyte contains sulfuric acid.
Avoid contact with skin, eyes, or cloth-
ing.
Antidotes
External: Flush with water.
Internal: Drink large quantities of water
or milk. Follow with milk of magnesia,
beaten egg, or vegetable oil. Call phy-
sician immediately.
Eyes: Flush with water for 15 minutes
and get prompt medical attention.
Batteries produce explosive gases.
Keep sparks, flame, cigarettes, etc.,
well away. If using or charging the bat-
tery in an enclosed space, make sure
that it is well ventilated. Always shield
your eyes when working near batter-
ies.
KEEP OUT OF THE REACH OF CHIL-
DREN.
Be sure to connect the breather hose
to the battery. Fire or explosion could
result if the breather hose is damaged,
obstructed, or not connected properly.
@
CAUTION:@ Be careful not to place the battery on
its side.
Be sure to remove the battery from the
battery compartment when adding
electrolyte or charging the battery.
@
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4-22
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To replenish the battery:
1. Make sure that the electrolyte level is
between the upper 1 and lower 2 level
marks.
2. Refill the battery with distilled water if
necessary.
CAUTION:@ Normal tap water contains minerals that
are harmful to a battery. Use only dis-
tilled water for replenishing the battery.
@
To recharge the battery:
CAUTION:@ Do not attempt to charge a battery hast-
ily. Battery life could be shortened.
@
It is recommended to have a Yamaha
dealer charge the battery. If you charge the
battery yourself, carefully read the battery
charger instructions before charging and fol-
low the points below.
1. Remove all caps from the battery cell.
2. Add distilled water to the specified level if
the electrolyte level is low.
3. Set the charging rate to 1.9 ampere and
charge the battery slowly until the explo-
sive gases are discharged vigorously
from the battery cells.
To connect the battery terminals:
1. Make sure that the connections are cor-
rect when you install the battery in the
watercraft.
2. Make sure that the breather hose is
properly connected and that it is not
damaged or obstructed.
3. Make sure that the battery is securely
held in place.
1Positive (+): Red lead
2Negative (–): Black lead
3Breather hose
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EJU11160
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.
EJU13670
Troubleshooting chart
TBC-F0P7ETROUBLE POSSIBLE CAUSE REMEDY PAGE
Engine does not
startStarter motor does not turn over
Yamaha
Security
SystemLock mode selected Select unlock mode
2-21
Engine shut-
off switchClip not in place Install clip
2-10
Fuse Burned out Replace the fuse and
check wiring4-24
Battery Run down Recharge 4-21
Poor terminal connec-
tionsTighten as required
4-21
Terminal corroded Clean 4-5
Starter motor Faulty Have serviced by
Yamaha dealer—
Starter motor turns over
Throttle lever Squeezed Release 2-11
Fuel Empty Refill as soon as possi-
ble3-4
Stale or contaminated Have serviced by
Yamaha dealer4-11
Fuel tank Water or dirt present Have serviced by
Yamaha dealer4-11
Spark plug Fouled or defective Clean or replace 4-16
Spark plug cap Not connected or loose Connect properly 4-16
Connected to wrong
cylinderConnect properly
4-16
Fuel injection
systemFuel pump faulty Have serviced by
Yamaha dealer—
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5-2
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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 dealer4-11
Fuel tank Water or dirt present Have serviced by
Yamaha dealer4-11
Spark plug Fouled or defective Replace 4-16
Incorrect heat range Replace 4-16
Gap incorrect Adjust 4-16
Spark plug cap Loose Connect properly 4-16
Cracked, torn, or dam-
agedReplace
—
Electrical wir-
ingLoose connection Tighten or connect
properly—
Fuel injection
systemJet nozzle clogged Have serviced by
Yamaha dealer—
Warning light or
indicator blinksFuel level Empty Refill as soon as possi-
ble3-4
Engine over-
heatedJet intake clogged Clean
5-3
Check engine
warningFaulty sensors Have serviced by
Yamaha dealer—
Wate rcr af t slow or
loses powerYamaha
Security
SystemLow-RPM mode
selectedSelect normal mode
2-22
Cavitation Jet intake clogged Clean 5-3
Impeller damaged or
wornHave serviced by
Yamaha dealer—
Engine over-
heat warningEngine speed reduc-
tion control activatedClean jet intake and
cool engine2-30
Oil pressure
warningEngine speed reduc-
tion control activatedAdd oil
2-30
Spark plug Fouled or defective Replace 4-16
Incorrect heat range Replace 4-16
Gap incorrect Adjust 4-16
Spark plug
capsLoose Connect properly
4-16
Electrical wir-
ingLoose connection Tighten or connect
properly—
Fuel Stale or contaminated Have serviced by
Yamaha dealer4-11
Air filter Clogged Clean or replace 4-14
Oil buildup Replace 4-14 TROUBLE POSSIBLE CAUSE REMEDY PAGE
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EJU18450
Connecting the jumper cables
1. Connect the positive (+) jumper cable 1
to the positive (+) terminals of both bat-
teries.
2. Connect one end of the negative (–)
jumper cable 2 to the negative (–) termi-
nal of the booster battery 3.
3. Connect the other end of the negative (–)
cable to an engine hanger 4.
CAUTION:@ Do not connect the end of the jumper
cable to the negative (–) terminal on the
watercraft battery! Be 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
then try again.
@
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Tilt lever................................................. 2-14
Towing the watercraft .............................. 5-7
Transporting .......................................... 3-38
Troubleshooting ...................................... 5-1
Troubleshooting chart ............................. 5-1
Turning the watercraft ........................... 3-31
U
“UNLOCK” indicator light....................... 2-26
W
“WARNING” indicator light .................... 2-26
Warning labels ........................................ 1-6
Watercraft characteristics...................... 1-18
Water separator ...................................... 3-8
Water-skiing .......................................... 1-19
Watertight compartment ........................ 2-38
Y
Yamaha Engine Management
System (YEMS)..................................... 2-20
Yamaha Security System ...................... 2-20
Yamaha Security System lock and
unlock modes ........................................ 2-21
Yamaha Security System/
Low-RPM mode .................................... 2-20
E_F1X-70.book Page 3 Friday, August 26, 2005 11:00 AM