2021 YAMAHA GP800R fuel

3-33
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EJU00679
Transporting
WARNING
Always place the fuel cock knob in the
“OFF” position when transporting the
watercraft, otherwise fuel could leak out
into the engine or engine compartment,
which would create a fire hazard.
When transporting the watercraft on a
trailer, secure the tie downs to the trailer
through the bow eye and stern rope holes.
CAUTION:
Do not route ropes or tie downs over the
seat, as they may leave permanent marks
on the seat’s surface. Also, wrap the
ropes or tie downs with towels or rags
where they touch the body of the water-
craft to avoid scratching or damage.

E
4
EJU00515
MAINTENANCE AND
CARE
Storage....................................................... 4-1
Flushing the cooling system ................... 4-1
Lubrication............................................... 4-3
Fuel system............................................. 4-4
Battery ..................................................... 4-5
Cleaning the watercraft........................... 4-6
Maintenance and adjustments............... 4-7
Owner’s/Operator’s Manual and tool
kit ............................................................. 4-8
Periodic maintenance chart .................... 4-9
Inspecting the fuel system .................... 4-10
Inspecting the oil injection system........ 4-12
Inspecting the steering cable................ 4-13
Inspecting and adjusting the throttle
cable ...................................................... 4-13
Inspecting the QSTS mechanism ........ 4-14
Cleaning and adjusting the spark
plugs ...................................................... 4-15
Lubrication points .................................. 4-16
Inspecting the battery ........................... 4-19
Adjusting the carburetor ....................... 4-21
Replacing the fuse ................................ 4-22
Bleeding the oil injection pump............. 4-22
Adjusting the Yamaha Adjustable
Sponson (Y.A.S.) .................................. 4-23
Specifications......................................... 4-24

4-1
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EJU00516a
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.
EJU00913a
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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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 is highly flammable and explo-
sive. A fire or explosion can cause
severe injury or death. Shut the engine
off. Drain in well-ventilated areas away
from flames or sparks. Do not smoke.
Avoid spilling gasoline. Wipe up spilled
gasoline immediately.
@
To drain the fuel system:
1. Place the fuel cock knob in the “OFF”
position.
2. Drain the fuel tank using a siphon.

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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.
(
●) This mark indicates maintenance that you may do yourself.
(
❍) This mark indicates work to be done by a Yamaha dealer.
*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)
MAINTENANCE INTERVAL INITIALTHEREAFTER
EVERYPA G E
10
hours50
hours100
hours100
hours200
hours
ITEM
3
months6
months6
months12
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, replace❍❍
4-11
Fuel tank Clean❍
4-11
Oil injection system Inspect, clean❍❍
4-12
Trolling speed Adjust●●
4-21
Carburetor throttle shaft Inspect❍❍
—
Cooling water passages Flush
● (after
ever y
use)4-1
Bilge strainer Clean●●●
—
Impeller Inspect●●●
—
Steering cable Inspect●●
4-13
QSTS mechanism Inspect ●●
4-14
Throttle cable Inspect, adjust●●
4-13
Stern drain plugs Inspect, replace●
3-7
Battery Inspect
●
(inspect
fluid level
before
ever y
use)
4-19
Rubber coupling Inspect❍
—
Nuts and bolts Tighten❍❍❍
—

4-10
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Inspecting the fuel system
WARNING
Gasoline and its vapors are highly flam-
mable and explosive.
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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Fuel filter
This watercraft is equipped with a one-
piece, disposable fuel filter 1. The fuel filter
should be replaced once a year or after
every 200 hours of operation, or if water is
found in the filter. Have a Yamaha dealer
replace the fuel filter if necessary.
WARNING
Do not try to replace the fuel filter your-
self. An incorrectly installed filter can
leak gasoline, which could lead to fire or
explosion. If necessary, have a Yamaha
dealer replace the fuel filter.
EJU00540
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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Specifications
MODEL
ITEMUnit GP800R
WATERCRAFT CAPACITY
Maximum people on board Number of people 2
Maximum load capacity kg (lb) 160 (353)
DIMENSIONS
Length mm (in) 2,930 (115.4)
Width mm (in) 1,150 (45.3)
Height mm (in) 1,020 (40.2)
Dry weight kg (lb) 268 (591)
PERFORMANCE
Maximum output kW (PS) @ r/min 88.2 (120)@ 7,000
Maximum fuel consumption L/h (US gal/h, Imp gal/h) 49.0 (12.9, 10.8)
Cruising range at full throttle hr. 1.2
Trolling speed r/min 1,250–1,350
ENGINE
Engine type 2-stroke
Number of cylinders 2
Engine displacement
cm
3 (cu in)784 (47.8)
Bore & stroke mm (in) 80.0 ×
78.0 (3.15 ×
3.07)
Compression ratio 6.6:1
Lubrication system Variable oil injection
Cooling system Water cooled
Starting system Electric starter
Ignition system Digital CDI
Spark plug BR8ES (NGK)
Spark plug gap mm (in) 0.7–0.8 (0.028–0.031)
Battery capacity V-AH 12-19
Charging system Flywheel magneto
DRIVE UNIT
Propulsion system Jet pump
Jet pump type Axial flow, single stage
Impeller rotation Counterclockwise (viewed from rear)
Transmission Direct drive from engine
Jet thrust nozzle angle Degree 23 + 23
Trim nozzle angle Degree -5, 0, 5, 10, 15
FUEL AND OIL
Recommended fuel Regular unleaded gasoline
Minimum octane rating PON
RON86
90
Recommended engine oil YAMALUBE 2-W, or an equivalent NMMA-
certified TC-W3 marine oil
Fuel tank capacity
Total L (US gal, Imp gal) 60 (15.9, 13.2)
Reserve L (US gal, Imp gal) 10 (2.6, 2.2)
Oil tank capacity L (US gal, Imp gal) 5.5 (1.45, 1.21)