engine YAMAHA GP800R 2003 Workshop Manual

4-1
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EJU01087
Storage
WARNING@ Always place the fuel cock knob in the
“OFF” position when storing the water-
craft, otherwise fuel could leak out into
the engine or engine compartment,
which would create 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.
EJU01088
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 seconds without supplying water,
otherwise the engine may overheat.
@
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1. Put the watercraft on land in a horizontal
position.
2. Open 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.
3. Connect the garden hose adapter to a
water tap using a hose.
4. Start the engine, and then immediately
turn the water supply on until water flows
out continually from the cooling water
pilot outlet.
5. 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.
6. 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.
7. Stop the engine.
8. Remove the garden hose adapter and
secure the cap.
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4-3
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EJU01299
Lubrication
WARNING@ To reduce the risk of fire or explosion:
Never pour or spray gasoline, or any sub-
stance other than a rust inhibitor through
the hole in the carburetor silencer cover.
@
CAUTION:@
Make sure to replace the cap securely
after fogging the engine, otherwise
water could enter the engine and
cause damage.

Do not attempt to run the engine at full
throttle or for more than 15 seconds
while the watercraft is out of the water,
otherwise the engine may overheat
and/or seize.
@
1. Open the silencer cap 1 on the silencer.
2. Start the engine with the watercraft in a
well-ventilated area.
3. With the engine running at a fast idle,
quickly spray as much rust inhibitor as
possible through the hole in the silencer
cover. Keep spraying until the engine
stalls (or a maximum of 15 seconds).
4. Install the cap securely.
5. Lubricate all cables such as the throttle,
choke, 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.
@
6. Lubricate the areas of the watercraft
specified under Lubrication points on
page 4-16.
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EJU01964
Fuel system
Draining the fuel system prevents buildup
of varnishes and other harmful deposits that
result when gasoline sits for a prolonged
period of time.
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 just reaches the
bottom of the filler tube. Do not fill up
the filler tube because fuel expands as
it warms up and could overflow. If tem-
porarily leaving the watercraft with a
full fuel tank, do not leave it in direct
sunlight. Leave it in a well-ventilated
area with the watercraft 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.
@
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4-6
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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.
@
EJU01093
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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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.
@
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EJU01355
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-***(
) 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


4-16
Intermediate housing Lubricate❍
*1

*2

*2 4-18
Fuel system Inspect❍❍
4-10
Fuel filter Check, clean, replace❍❍
4-11
Fuel tank Clean❍
4-11
Oil injection system Inspect, clean❍❍
4-12
Trolling speed Inspect, adjust


4-21
Carburetor throttle shaft Inspect❍❍
—
Cooling water passages Flush

*3 4-1
Water inlet strainer Inspect, clean❍❍
—
Bilge strainer Clean


—
Impeller Inspect

*4❍❍
—
Jet thrust nozzle angle Inspect


4-13
QSTS mechanism Inspect, adjust

*4❍❍
4-14
Throttle lever Check operation

*4 3-10
Throttle cable Inspect, adjust❍❍
4-13
Choke lever Check operation

*4 2-8
Choke cable Inspect, adjust❍❍
—
Stern drain plugs Inspect, replace

*4❍❍
3-7
Battery Inspect

*5❍❍
4-19
Rubber coupling Inspect❍
—
Engine mount Inspect❍
—
Nuts and bolts Inspect❍❍❍
—
*1: Grease capacity: 33.0–35.0 cm3 (1.11–1.18 oz)
*2: Grease capacity: 6.0–8.0 cm3 (0.20–0.27 oz)
*3: After every use
*4: Before every use
*5: Inspect fluid level before every use
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EJU01383
Inspecting the fuel system
WARNING@ Gasoline is highly flammable and explo-
sive. A fire or explosion can cause
severe injury or death. Shut off the
engine. Do not smoke. Avoid spilling
gasoline.
@
Check the fuel system for leaks, cracks,
or malfunctions. If any problem is found, do
the necessary repair or replacement as
required. If repair is necessary, consult a
Yamaha dealer.
Check:

Carburetor for leakage.

Fuel pump for malfunction or leakage.

Fuel tank for water or dirt.

Fuel tank for damage, cracks or leakage.

Fuel hose joint for leakage.

Fuel hose for cracks or other damage.

Fuel filter for leakage.

Fuel cock for leakage.

Air vent check valve for leakage.

Fuel tank filler cap for damage.
WARNING@ Failure to check for and repair any fuel
leakage may result in fire or explosion.
@
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4-15
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EJU01341
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 the center electrode porcelain is
very white, this could indicate an intake air
leak or carburetion problem in that cylinder.
Do not attempt to diagnose any problems
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.
Measure the spark plug gap a with a
wire thickness gauge before installing the
spark plug. Adjust the gap to specification if
necessary.
To reinstall spark plug:
1. Clean the gasket surface.
2. Wipe any dirt from the threads of the
spark plug.
3. Screw the spark plug to the correct
torque. Standard spark plug: BR8ES
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Spark plug torque:
25 N·m (2.5 kgf·m, 18 ft·lb)
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EJU01109
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.
@
EJU01344
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 or, if necessary, the tachometer in the
multifunction information center, adjust
the engine speed to specification.
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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