2021 YAMAHA GP800R spark plugs replace

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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.

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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❍❍❍
—

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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)