engine YAMAHA VX 2005 Repair Manual

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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.
EJU21260
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 of the watercraft
for more than 15 seconds without sup-
plying water, otherwise the engine may
overheat.
@
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1. Put the watercraft on land in a horizontal
position.
2. Remove the seat. (See page 2-5 for seat
removal and installation procedures.)
3. Remove the flushing hose connector
cap1, and then insert the garden hose
adapter 2 into the flushing hose con-
nector 3 and turn it until it is securely
connected.
4. Connect the garden hose adapter to a
water tap using a hose.
5. Start the engine, and then immediately
turn the water supply on until water flows
out continually from the jet nozzle.
6. Run the engine at idling speed for about
3 minutes watching the engine condition.
If the engine stops while flushing, turn
the water supply off immediately and
repeat the above steps.
7. Turn the water supply off, and then force
the remaining water out from the cooling
passages by alternately squeezing and
releasing the throttle lever for 10 to
15 seconds.
8. Stop the engine.
9. Remove the garden hose adapter and
install the cap.
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EJU21270
Lubrication
WARNING@ Do not spray flammable rust inhibitor
products on engine surfaces while the
engine is hot. The sprayed substance or
propellants could catch fire.
@
1. Remove the seat. (See page 2-5 for seat
removal and installation procedures.)
2. Loosen the clamp screw 1 and discon-
nect the air intake duct 2.
3. Spray a rust inhibitor into the intake
opening 3 for 3 seconds.
4. Connect the air intake duct and tighten
the clamp screw.
5. Start the engine in a well-ventilated area
and let it run at idle for 15 seconds.
CAUTION:@ Do not run the engine for more than
15 seconds. The engine could overheat.
@
6. Lubricate all cables such as the throttle
and steering cables.
NOTE:@ Use a suitable marine grease applicator to
pressure lubricate the cables and purge out
any moisture between the inner and outer
cables.
@
7. Lubricate the areas of the watercraft
specified under Lubrication points on
page 4-17.
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EJU19652
Fuel system
WARNING@ GASOLINE AND ITS VAPORS ARE
HIGHLY FLAMMABLE AND EXPLOSIVE!

Do not smoke when refueling, and
keep away from sparks, flames, or
other sources of ignition.

Stop engine before refueling.

Refuel in a well-ventilated area with
the watercraft in a horizontal position.

Do not stand or sit on the watercraft
while refueling in case of fire.

Take care not to spill gasoline. If gaso-
line spills, wipe it up immediately with
dry rags. Always properly dispose of
gasoline-soaked rags.

Avoid overfilling the fuel tank. Stop fill-
ing when the fuel level reaches approx-
imately 50 mm (2 in) from the top of the
fuel tank. Fuel expands as it warms up
and could overflow if the fuel tank has
been overfilled. If temporarily leaving
the watercraft with a full fuel tank, do
not leave it in direct sunlight. Leave it
in a well-ventilated area with the water-
craft in a horizontal position.

Tighten the filler cap securely after
refueling.

If you should swallow some gasoline,
inhale a lot of gasoline vapor, or get
gasoline in your eyes, get immediate
medical attention.

If any gasoline spills onto your skin,
immediately wash with soap and
water. Change clothing if gasoline
spills on it.
@
Top off the fuel tank with fresh gasoline
and add fuel stabilizer and conditioner to the
fuel tank by following the manufacturer’s
instructions carefully.
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NOTE:@ The condition of the battery can be known
by checking the specific gravity of the elec-
trolyte. However, you can also know the con-
dition of the battery by measuring the
voltage at both battery terminals. Charge
the battery if the voltage is less than
12 volts.
It is recommended to have a Yamaha dealer
check the specific gravity and to charge the
battery. If you maintain the battery yourself,
be sure to read and follow the instructions
provided with the battery tester and charger
you use.
@
EJU10930
Cleaning the watercraft
Clean the watercraft before storing it for a
long period.
1. Wash down the hull, handlebars, and
drive unit with fresh water.
2. Rinse the engine and bilge area with
fresh water. Drain off all water and wipe
up remaining moisture with clean, dry
rags.
3. Spray the engine’s exterior with a rust
inhibitor and lubricant.
4. Wax the hull with a non-abrasive wax.
5. Wipe all vinyl and rubber components,
such as the seat and engine compart-
ment seals, with a vinyl protectant. Specific gravity (for reference):
1.28 at 20 °C (68 °F)
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EJU10940
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.
@
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EJU13550
Periodic maintenance chart
The following chart gives general guidelines for periodic maintenance. However, depend-
ing on your operating conditions maintenance may need to be performed more frequently.
PMC-F1B1(
) This mark indicates maintenance that you may do yourself.
(
❍) This mark indicates work to be done by a Yamaha dealer.
MAINTENANCE INTERVAL
INITIALTHEREAFTER
EVERYPA G E
10
hours50
hours100
hours100
hours200
hours
ITEM
6
months12
months12
months24
months
Spark plug Inspect, clean, adjust



4-15
Lubrication points Lubricate


4-17
Fuel system Inspect❍❍
4-10
Fuel tank Inspect, clean❍❍
4-10
Trolling speed Inspect❍❍
4-21
Throttle shaft Inspect❍❍
—
Cooling water passages Flush

*1 4-1
Water inlet strainer Inspect, clean❍❍
—
Bilge strainer Clean❍❍
—
Impeller Inspect❍❍
—
Jet thrust nozzle angle Inspect, adjust

/❍

/❍
4-13
Shift cable and mechanism
(VX110 Deluxe)Inspect, adjust
❍❍
4-13
Throttle cable Inspect, adjust❍❍❍
4-14
Stern drain plugs Inspect, replace❍❍
3-9
Battery Inspect ❍❍
4-19
Rubber coupling Inspect❍
—
Engine mount Inspect❍
—
Nuts and bolts Inspect❍❍❍
—
Air filter Inspect, replace❍❍
4-13
Engine oil Replace❍❍❍
4-11
Engine oil filter Replace❍❍
—
Valve clearance Inspect, adjust❍
—
*1: After every use
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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.
@
UF1K70.book Page 12 Friday, November 19, 2004 2:42 PM