Checking The Cooling System; Changing The Coolant - Yamaha YZ450FN 2022 Owner's Service Manual

tilled water is not available, soft water may
be used.
4. Start the engine, warm this up for several
minutes, and then stop it.
5. Check:
• Coolant level
TIP
Before checking the coolant level, wait a few
minutes until the coolant has settled.
EAM30211

CHECKING THE COOLING SYSTEM

1. Remove:
• Seat
• Side cover (left/right)
• Air scoop (left/right)
Refer to "GENERAL CHASSIS" on page 4-1.
2. Check:
• Radiator
• Radiator hose
Crack/damage  Replace.
Refer to "RADIATOR" on page 6-2.
3. Install:
• Air scoop (left/right)
• Seat
• Side cover (left/right)
Refer to "GENERAL CHASSIS" on page 4-1.
EAM30212

CHANGING THE COOLANT

EWA13030
WARNING
A hot radiator is under pressure. Therefore,
do not remove the radiator cap when the en-
gine is hot. Scalding hot fluid and steam may
be blown out, which could cause serious in-
jury. When the engine has cooled, open the
radiator cap as follows:
Place a thick rag or a towel over the radiator
cap and slowly turn the radiator cap counter-
clockwise toward the detent to allow any re-
sidual pressure to escape. When the hissing
sound has stopped, press down on the radi-
ator cap and turn it counterclockwise to re-
move.
1. Place a container under the engine.
2. Remove:
• Coolant drain bolt "1"
3. Remove:
• Radiator cap
Slowly loosen the radiator cap to drain cool-
ant.
TIP
When the radiator cap is loosened, coolant will
gush out transversely; therefore, bring the con-
tainer near to the outlet.
4. Thoroughly flush the cooling system with
clean tap water.
5. Install:
• Copper washer
• Coolant drain bolt
Coolant drain bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
6. Pour coolant.
Recommended coolant
High quality ethylene glycol
anti-freeze containing anti-cor-
rosion for aluminum engine
Radiator (including all routes)
1.03 L (1.09 US qt, 0.91 Imp.qt)
Coolant mixing ratio
1:1 (Coolant:Water)
EWA13040
WARNING
• If coolant splashes in your eyes, thorough-
ly wash them with water and consult a doc-
tor.
• If coolant splashes on your clothes, quickly
wash it away with water and then with soap
and water.
• If coolant is swallowed, induce vomiting
and get immediate medical attention.
ECA13481
NOTICE
• Adding water instead of coolant lowers the
antifreeze content of the coolant. If water is
used instead of coolant, check, and if nec-
essary, correct the antifreeze concentra-
3-21
ENGINE
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