spark plugs YAMAHA GP800R 2021 Owners Manual

2-4
E
1Spark plugs/Spark plug caps
2Electrical box
Protects electrical components from water.
3Flush hose connector
Use to flush the engine cooling water pas-
sages.
4Spark plug lead
5Muffler
6Fuel filter
7Fuel tank8Oil tank
9Battery
0Fire extinguisher container
AWater separator

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

4-3
E
EJU00526a
Lubrication
WARNING
To reduce the risk of fire or explosion:
Never pour or spray gasoline, or any sub-
stance other than engine fogging oil
through the holes in the carburetor
silencer cover.
CAUTION:
●Be sure to replace the caps 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 fogging oil as pos-
sible 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. Remove the spark plugs and pour
approximately one tablespoon of engine
oil into each cylinder. Grease the spark
plug threads and install the spark plugs.
6. Crank the engine for 3 seconds.
7. Lubricate all cables such as the throttle,
choke, and steering cables.
8. Lubricate the areas of the watercraft
specified under Lubrication points on
page 4-16.

4-9
E
EJU00536
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❍❍❍
—

4-15
E
EJU00552a
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)

5-8
E
EJU00604a
Submerged watercraft
If the watercraft is submerged or flooded
with water, follow the procedure below and
consult a Yamaha dealer as soon as possi-
ble. Failure to do so may result in serious
engine damage!
1. Beach the watercraft and remove the
stern drain plugs to drain the water from
the engine compartment.
2. Turn the fuel cock knob to “OFF.”
3. Remove the spark plugs and dry them
with a cloth.
4. Without reinstalling the spark plugs,
crank the engine until all the water in the
cylinders has been drained.
5. Install the stern drain plugs and the
spark plugs.
6. Turn the fuel cock to “ON.”
7. Launch the watercraft into the water, and
then run the engine for at least
10 minutes. If the engine will not start,
repeat steps above.
8. Turn the engine off. Turn the fuel cock to
“OFF.”
9. Remove the silencer cap and spray a
rust inhibitor into the carburetor while
cranking the engine.
10. Have the watercraft inspected by a
Yamaha dealer as soon as possible.

6-1
E
EJU00609
Index
2-stroke engine oil ................................... 3-4
A
Adjusting the carburetor ........................ 4-21
Adjusting the trolling speed ................... 4-21
Adjusting the Yamaha Adjustable
Sponson (Y.A.S.) .................................. 4-23
Approval label of Emission control
certificate ................................................. 1-2
B
Battery .............................................. 3-8, 4-5
Beaching the watercraft ........................ 3-30
Bilge ........................................................ 3-7
Bleeding the oil injection pump ............. 4-22
Boarding alone ...................................... 3-23
Boarding and starting in deep water ..... 3-23
Boarding with a passenger.................... 3-24
Bow down.............................................. 2-12
Bow up .................................................. 2-12
C
Capsized watercraft .............................. 3-25
Caution labels ......................................... 1-7
Choke lever ............................................. 2-8
Cleaning and adjusting the spark
plugs...................................................... 4-15
Cleaning the jet intake and impeller ........ 5-4
Cleaning the watercraft ........................... 4-6
Connecting the jumper cables................. 5-6
Cooling water pilot outlet .............. 2-10, 3-12
Cruising limitations ................................ 1-10
D
Docking the watercraft .......................... 3-30
E
Emergency procedures ........................... 5-4
Emission control information ................... 1-2
Engine break-in ..................................... 3-13
Engine compartment ............................... 3-6
Engine overheat warning indicator ........ 2-18
Engine overheat warning system .......... 2-13
Engine serial number .............................. 1-1Engine shut-off cord (lanyard) ............... 3-11
Engine shut-off switch ............................. 2-8
Engine stop switch .................................. 2-8
Enjoy your watercraft responsibly ......... 1-15
F
Filling the fuel tank .................................. 3-3
Filling the oil tank .................................... 3-4
Fire extinguisher ...................................... 3-9
Flushing the cooling system .................... 4-1
Front storage compartment ................... 2-19
Fuel and oil.............................................. 3-1
Fuel and oil systems ............................... 3-6
Fuel cock knob ........................................ 2-7
Fuel filter ............................................... 4-11
Fuel meter ............................................. 2-17
Fuel system ............................................. 4-4
Fuel tank ............................................... 4-11
Fuel tank filler cap ................................... 2-6
Fuel warning indicator ........................... 2-18
G
Gasohol ................................................... 3-2
Gasoline .................................................. 3-1
Getting to know your watercraft ............ 3-19
Glove compartment ............................... 2-20
H
Handgrip ................................................ 2-14
Hazard information ................................ 1-13
Hood........................................................ 2-6
Hour meter ............................................ 2-17
Hull Identification Number (HIN).............. 1-1
I
Identification numbers ............................. 1-1
Important labels ....................................... 1-3
Inspecting and adjusting the throttle
cable...................................................... 4-13
Inspecting the battery ............................ 4-19
Inspecting the fuel system ..................... 4-10
Inspecting the oil injection system ......... 4-12
Inspecting the QSTS mechanism .......... 4-14
Inspecting the steering cable................ 4-13
J
Jet unit................................................... 3-11
Jumping the battery ................................. 5-5