2003 YAMAHA FX service

4-1
E
EJU18121
Storage
WARNING@ Always place the watercraft upright in a
horizontal position when storing it, oth-
erwise fuel could leak out into the engine
or engine compartment, which could
result in a fire hazard.
@
Storage for prolonged periods of time,
such as winter storage, requires preventa-
tive maintenance to ensure against deterio-
ration. It is advisable to have the watercraft
serviced by a Yamaha dealer prior to stor-
age. However, the following procedures can
be performed by the owner.
EJU01813
Flushing the cooling system
Flushing the cooling system is essential
to prevent the cooling system from being
clogged with salt, sand, or dirt.
CAUTION:@
Do not supply water to the cooling
water passages when the engine is not
running. The water could flow back
through the muffler into the crankcase
causing severe engine damage.

Do not run the engine for more 15 sec-
onds without supplying water, other-
wise the engine may overheat.
E_F1B-70-4.fm Page 1 Tuesday, November 19, 2002 3:21 PM

4-7
E
EJU01094
Maintenance and
adjustments
Periodic inspection, adjustment and lubri-
cation will keep your watercraft in the safest
and most efficient condition possible. Safety
is an obligation of the watercraft owner. The
most important points of watercraft inspec-
tion, adjustment and lubrication are
explained on the following pages.
See your Yamaha dealer for genuine
Yamaha replacement parts and optional
accessories designed for your watercraft.
Remember that failures that are the result
of the installation of parts or accessories
which are not qualitatively equivalent to gen-
uine Yamaha parts are not covered by the
limited warranty.
WARNING@
Be sure to turn off the engine when
you perform maintenance unless oth-
erwise specified, otherwise an acci-
dent or injury could result from
unexpected operation, moving parts,
or electric shock. If the owner is not
familiar with watercraft servicing, this
work should be done by a Yamaha
dealer. Improperly serviced compo-
nents could fail or stop operating cor-
rectly, which could result in an
accident.

Modifications to this watercraft not
approved by Yamaha may cause loss
of performance or excessive noise, or
render it unsafe for use. Consult a
Yamaha dealer before attempting any
changes.
UF1B71.book Page 7 Tuesday, November 12, 2002 4:17 PM

4-8
E
EJU01875
Owner’s/Operator’s Manual
and tool kit
It is advisable always to carry the
Owner’s/Operator’s Manual and tool kit 2
with you whenever you use the watercraft.
For your convenience, a storage compart-
ment 1 is provided on the watercraft for the
manual and tool kit.
NOTE:@ To protect these materials from water dam-
age, it would be a good idea to put them in a
waterproof bag.
The service information included in this
manual is intended to provide you with the
necessary information for completing your
own preventive maintenance and minor
repairs. The tools provided in the tool kit are
sufficient for this purpose.
UF1B71.book Page 8 Tuesday, November 12, 2002 4:17 PM

4-10
E
EJU01816
Inspecting the fuel system
WARNING@ Gasoline is highly flammable and explo-
sive. Failure to check for and repair any
fuel leakage could result in fire or explo-
sion. A fire or explosion can cause
severe injury or death. Shut off the
engine. Do not smoke. Avoid spilling
gasoline.
Fuel in hose is pressurized.
Fuel can spray out and cause injury or a
fire hazard if fuel line is disconnected.
Do not attempt to run engine with fuel
line disconnected.
Check the fuel system for leaks, cracks,
or malfunctions. If any problem is found,
consult a Yamaha dealer.
Check:

Fuel tank for water or dirt.

Fuel tank cap (seal) for damage.

Fuel tank for damage, cracks or leakage.

Fuel hose joint for leakage.

Fuel hose for cracks or other damage.

Air bleeding passages for leakage.
EJU01841
Fuel tank
Check the fuel tank 1 for leakage or
water in the tank. If water is found in the fuel
system or if the fuel tank needs to be
cleaned, have a Yamaha dealer service the
watercraft.
UF1B71.book Page 10 Tuesday, November 12, 2002 4:17 PM

4-14
E
EJU01897
Inspecting the jet thrust nozzle
angle
Check for smooth operation of the handle-
bars and jet thrust nozzle.
Turn the handlebars as far as possible to
the right and left and check that the distance
between the jet thrust nozzle and the
bracket of the reverse gate are equal on
right and left sides.
If steering is stiff or misadjusted, have a
Yamaha dealer service it.
EJU01852
Inspecting the shift cable
Place the shift lever in the reverse posi-
tion.
Make sure that the reverse gate makes
contact with the stopper 1 on the bracket,
and that the arm 2 makes contact with the
reverse gate.
If the reverse gate does not reach the cor-
rect positions, have a Yamaha dealer ser-
vice it.
EJU01104
Inspecting and adjusting the
throttle cable
Check that the throttle cable moves back
to the set position smoothly and that free
play is within specification.
1. Squeeze and release the throttle lever. If
the lever does not return smoothly, have
a Yamaha dealer service it.
2. Adjust free play a by loosening the lock-
nut 1 and turning the adjuster 2. Distance A and B: A = B
Throttle lever free play:
4–7 mm (0.16–0.28 in)
UF1B71.book Page 14 Tuesday, November 12, 2002 4:17 PM

4-15
E
EJU01842
Inspecting the QSTS
mechanism
Check that the shift lock lever moves back
to the lock position smoothly, that the QSTS
selector locks and unlocks properly, and that
the jet thrust nozzle moves up or down.
1. Squeeze and release the shift lock lever.
2. Check that the QSTS selector locks
when the lever is released.
3. Check that the selector turns smoothly
when the lever is squeezed and held in
place.
4. Check that the angle of the jet thrust
nozzle changes when the selector is
shifted from neutral to bow up or bow
down.
If the mechanism does not work properly,
have a Yamaha dealer service it.
UF1B71.book Page 15 Tuesday, November 12, 2002 4:17 PM

4-16
E
EJU18201
Cleaning and adjusting the
spark plugs
The spark plug is an important engine
component and is easy to inspect. The con-
dition of the spark plug can indicate some-
thing about the condition of the engine. For
example, if one spark plug shows a distinctly
different color, the engine could be defec-
tive. Do not attempt to diagnose any prob-
lems yourself. Have a Yamaha dealer
service the watercraft.
Remove and inspect the spark plug peri-
odically; heat and deposits will cause the
spark plug to slowly break down and erode.
If electrode erosion becomes excessive, or if
carbon and other deposits are excessive,
replace the spark plug with the specified
plug.
Removing a spark plug:
1. Remove the air filter case cover and air
filter element. (See page 4-13 for air filter
removal and installation procedures.)
2. Remove the spark plug.
Measure the spark plug gap a with a
wire thickness gauge. Replace the spark
plugs or adjust the gap to specification if
necessary.Specified spark plug: NGK CR9EB
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
UF1B71.book Page 16 Tuesday, November 12, 2002 4:17 PM

5-1
E
EJU01116
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.
EJU01367
Troubleshooting chart
TBC-F0P7ETROUBLE POSSIBLE CAUSE REMEDY PAGE
Engine does not
startStarter motor does not turn over
Engine shut-
off switchClip not in place Install clip
2-8
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 2-8
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 dealer4-10
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—
UF1B71.book Page 1 Tuesday, November 12, 2002 4:17 PM