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EJU18160
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.
EJU18410
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.
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EJU21590
Changing the engine oil
WARNING@ Engine oil is extremely hot immediately
after the engine is turned off. Coming
into contact with or getting any engine
oil on your clothes could result in burns.
@
CAUTION:@ Do not run the engine with too much or
not enough oil in the oil tank. Oil could
spray out and the engine could be
damaged.
Be sure to change the engine oil after
the first 10 hours of operation, and
every 100 hours thereafter or at the
start of a new season, otherwise the
engine will wear quickly.
The oil filter should be replaced every
year or every 100 hours of operation.
Have a Yamaha dealer replace the oil
filter if necessary.
@
It is recommended to have a Yamaha
dealer change the engine oil. However, if
you choose to change the oil on your own,
consult a Yamaha dealer.
NOTE:@ Dispose of used oil according to local regu-
lations.
@
Recommended engine oil:
See page 3-3.
Oil quantity:
With oil filter replacement:
2.2 L (2.3 US qt, 1.9 Imp qt)
Without oil filter replacement:
2.0 L (2.1 US qt, 1.8 Imp qt)
Total amount:
4.3 L (4.5 US qt, 3.8 Imp qt)
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CAUTION:@ If oil is leaking or the oil pressure warn-
ing indicator comes on when the engine
is running, immediately turn the engine
off and have a Yamaha dealer check the
watercraft. Continuing to operate the
engine under such conditions could
cause severe engine damage.
@
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EJU21280
Checking the air filter element
Have a Yamaha dealer check and clean
or replace the air filter element every
12 months or every 100 hours of operation.
EJU18891
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 differ-
ence of distances A and B between the jet
thrust nozzle and the nozzle is within specifi-
cation.
If steering is stiff or misadjusted, have a
Yamaha dealer service it.
EJU21290
Inspecting the shift cable
(for VX110 Deluxe)
Place the shift lever in the reverse posi-
tion.
Make sure that the reverse gate makes
contact with the stopper 1.
If the reverse gate does not make contact
with the stopper, have a Yamaha dealer ser-
vice it. Difference of A and B:
Maximum 5 mm (0.20 in)
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EJU11040
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.
Throttle lever free play:
4–7 mm (0.16–0.28 in)
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EJU21300
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 plugs peri-
odically; heat and deposits will cause the
spark plugs 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.
To remove a spark plug:
1. Remove the seat. (See page 2-5 for seat
removal and installation procedures.)
2. Remove the spark plug cap.
CAUTION:@ Do not use any tools to remove or install
the spark plug cap, otherwise the igni-
tion coil coupler may be damaged. The
spark plug cap may be difficult to remove
because the rubber seal on the end of
the cap fits tightly. To remove the spark
plug cap, simply twist it back and forth
while pulling it up; to install it, twist it
back and forth while pushing it down.
@
3. Remove the spark plug.Specified spark plug: NGK CR9EB
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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 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 specification.
4. Install the spark plug cap.
NOTE:@ Wipe off any water on the spark plug or
inside 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 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 cor-
rect 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.
@
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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EJU21310
Lubrication points
To keep moving parts sliding or rotating
smoothly, coat them with water-resistant
grease.
Recommended water-resistant grease:
Yamaha Marine Grease/
Yamaha Grease A
Throttle cable (handlebar end)
Pull the throttle lever and remove the
seal1. Spray a rust inhibitor into the
outer cable. Refit the seal securely.
Steering cable (handlebar end)
Steering cable (nozzle end)
Nozzle pivot shaft
UF1K70.book Page 17 Friday, November 19, 2004 2:42 PM