ENGINE
3-21
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.
•
Air filter case cover
Refer to “THROTTLE BODY” on page 7-4.
2. Check:
•
Radiator
•
Radiator hose
Crack/damage
Replace.
Refer to “RADIATOR” on page 6-2.
3. Install:
•
Air filter case cover
Refer to “THROTTLE BODY” on page 7-4.
•
Air scoop (left/right)
•
Seat
•
Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 4-1.
EAM30212
CHANGING THE COOLANT
WARNING
EWA13030
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
6. Pour coolant.
WARNING
EWA13040
• 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.
NOTICE
ECA13481
• 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-
Coolant drain bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
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)
1
1
Ne
w
T
R
.
.
Summary of Contents for YZ450F 2021
Page 6: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY ...
Page 10: ......
Page 44: ...MOTORCYCLE CARE AND STORAGE 1 32 ...
Page 61: ...TIGHTENING TORQUES 2 16 ...
Page 62: ...CABLE ROUTING DIAGRAM 2 17 EAM20152 CABLE ROUTING DIAGRAM Frame and engine left side view ...
Page 64: ...CABLE ROUTING DIAGRAM 2 19 Frame and engine right side view ...
Page 66: ...CABLE ROUTING DIAGRAM 2 21 Handlebar front view ...
Page 68: ...CABLE ROUTING DIAGRAM 2 23 Frame and engine top view ...
Page 70: ...CABLE ROUTING DIAGRAM 2 25 Frame and battery top view ...
Page 72: ...CABLE ROUTING DIAGRAM 2 27 Rear brake right side view ...
Page 74: ...CABLE ROUTING DIAGRAM 2 29 ...
Page 112: ...ELECTRICAL SYSTEM 3 36 ...
Page 148: ...REAR BRAKE 4 34 system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 25 ...
Page 189: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 3 1 Connecting rod 2 Oil nozzle 3 Crankshaft ...
Page 191: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 5 1 Oil filter element 2 Oil pump 3 Oil strainer ...
Page 262: ...TRANSMISSION 5 76 ...
Page 272: ...WATER PUMP 6 9 ...
Page 282: ...THROTTLE BODY 7 9 ...
Page 289: ...IGNITION SYSTEM 8 6 ...
Page 290: ...ELECTRIC STARTING SYSTEM 8 7 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM ...
Page 294: ...CHARGING SYSTEM 8 11 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM ...
Page 297: ...CHARGING SYSTEM 8 14 ...
Page 298: ...FUEL INJECTION SYSTEM 8 15 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM ...
Page 321: ...FUEL INJECTION SYSTEM 8 38 ...
Page 322: ...FUEL PUMP SYSTEM 8 39 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM ...
Page 352: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15 ...
Page 362: ...CHASSIS 10 9 ...
Page 364: ......
Page 366: ......
Page 368: ...YZ450FM 2021 WIRING DIAGRAM B2W 2819U 11_W D indd 2 2020 02 05 10 21 39 ...