radiator YAMAHA WR 450F 2008 User Guide

3-10
ENGINE
Handling notes of coolant:
The coolant is harmful so it should be
handled with special care.
• When coolant splashes to your
eye.
Thoroughly wash your eye with
water and see your doctor.
• When coolant splashes to your
clothes.
Quickly wash it away with water
and then with soap.
• When coolant is swallowed.
Quickly make him vomit and take
him to a doctor.
9. Install:
• Radiator cap
Start the engine and warm it up
for a several minutes.
10. Check:
• Coolant level
Coolant level low→Add coolant.
CHECKING THE RADIATOR CAP
1. Inspect:
• Seal (radiator cap) "1"
• Valve and valve seat "2"
Crack/damage→Replace.
Exist fur deposits "3" →Clean or
replace.
CHECKING THE RADIATOR CAP
OPENING PRESSURE
1. Attach:
• Radiator cap tester "1" and adapt-
er "2"
Apply water on the radiator cap seal.
3. Radiator cap
2. Apply the specified pressure.
3. Inspect:
•Pressure
Impossible to maintain the speci-
fied pressure for 10 seconds→
Replace.
CHECKING THE COOLING
SYSTEM
1. Inspect:
• Coolant level
2. Attach:
• Radiator cap tester "1" and adapt-
er "2"
3. Apply the specified pressure.
• Do not apply pressure more than
specified pressure.
• Radiator should be filled fully.
4. Inspect:
•Pressure
Impossible to maintain the speci-
fied pressure for 10 seconds→
Repair.
• Radiator• Radiator hose joint
Coolant leakage→Repair or re-
place.
• Radiator hose
Swelling→Replace.
ADJUSTING THE CLUTCH CABLE
FREE PLAY
1. Check:
• Clutch lever free play "a"
Out of specification→Adjust.
2. Adjust:
• Clutch lever free play
Clutch lever free play adjustment
steps:
a. Loosen the locknuts "1".
b. Turn the adjuster "2" until free
play "a" is within the specified lim-
its.
c. Tighten the locknuts.
• Make minute adjustment on the le-
ver side using the adjuster "3".
• After adjustment, check proper op-
eration of clutch lever.
ADJUSTING THE THROTTLE
CABLE FREE PLAY
1. Check:
• Throttle grip free play "a"
Out of specification→Adjust. Radiator cap tester:
YU-24460-01/90890-
01325
Radiator cap tester
adapter:
YU-33984/90890-01352
Radiator cap opening
pressure:
110 kPa (1.1 kg/cm
2,
15.6 psi)
Radiator cap tester:
YU-24460-01/90890-
01325
Radiator cap tester
adapter:
YU-33984/90890-01352
Standard pressure:
180 kPa (1.8 kg/cm
2,
25.6 psi)
Clutch lever free play "a"
:
8–13 mm (0.31–0.51 in)
Locknut:
4 Nm (0.4 m•kg, 2.9
ft•lb)
Throttle grip free play
"a":
3–5 mm (0.12–0.20 in)

5-1
RADIATOR
ENGINE
RADIATOR
REMOVING THE RADIATOR
Order Part name Q'ty Remarks
Drain the coolant.Refer to "CHANGING THE COOLANT" sec-
tion in the CHAPTER 3.
Seat, fuel tank and left side coverRefer to "REMOVING THE SEAT, FUEL
TANK AND SIDE COVERS" section in the
CHAPTER 3.
Exhaust pipeRefer to "REMOVING THE EXHAUST PIPE
AND SILENCER" section in the CHAPTER 3.
1 Radiator guard 2
2 Radiator hose clamp 8
3 Right radiator 1
4 Radiator hose 2 1
5 Radiator hose 3 1
6 Radiator hose 4 1
7 Pipe 2/O-ring 1/1
8 Catch tank hose 1
9 Left radiator 1
10 Radiator hose 1 1
5

5-2
RADIATOR
11 Pipe 1/O-ring 1/1
12 Catch tank breather hose 1
13 Catch tank 1 Order Part name Q'ty Remarks

5-3
RADIATOR
HANDLING NOTE
Do not remove the radiator cap
when the engine and radiator are
hot. Scalding hot fluid and steam
may be blown out under pressure,
which could cause serious injury.
When the engine has cooled, open
the radiator cap by the following
procedure:
Place a thick rag, like a towel, over
the radiator cap, slowly rotate the
cap counterclockwise to the de-
tent. This procedure allows any re-
sidual pressure to escape. When
the hissing sound has stopped,
press down on the cap while turn-
ing counterclockwise and remove
it.
CHECKING THE RADIATOR
1. Inspect:
• Radiator core "1"
Obstruction→Blow out with com-
pressed air through rear of the ra-
diator.
Bent fin→Repair/replace.
INSTALLING THE RADIATOR
1. Install:
• Pipe 1 "1"
• Radiator hose 1 "2"
• Pipe 2 "3"
• Radiator hose 3 "4"
• Radiator hose 4 "5"2. Install:
• Radiator hose 2 "1"
• Left radiator "2"
3. Install:
• Catch tank hose "1"
• Right radiator "2"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.
4. Install:
• Radiator guard "1"
First fit the inner hook portion "a" and
then the outer one "b" onto the radia-
tor.
5. Install:
• Catch tank "1"
• Bolt (catch tank) "2"
• Bolt (catch tank) "3"
• Catch tank hose "4"
• Catch tank breather hose "5"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.
Pipe 1:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Radiator hose 1:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Pipe 2:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Radiator hose 3:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Radiator hose 4:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Radiator hose 2:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Left radiator:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Right radiator:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (catch tank):
7 Nm (0.7 m•kg, 5.1
ft•lb)
Bolt (catch tank):
16 Nm (1.6 m•kg, 11
ft•lb)

5-20
CYLINDER HEAD
CYLINDER HEAD
REMOVING THE CYLINDER HEAD
Tighten the cylinder head bolts to 30 Nm (3.0 m•kg, 22 ft•lb) in the proper tightening sequence, remove and retighten the
cylinder head bolts to 20 Nm (2.0 m•kg, 14 ft•lb) in the proper tightening sequence, and then tighten the cylinder head bolts
further to reach the specified angle 180° in the proper tightening sequence.
Order Part name Q'ty Remarks
Seat and fuel tank Refer to "REMOVING THE SEAT, FUEL
TANK AND SIDE COVERS" section in the
CHAPTER 3.
Exhaust pipe and silencerRefer to "REMOVING THE EXHAUST PIPE
AND SILENCER" section in the CHAPTER 3.
Radiator Refer to "RADIATOR" section
Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section.
Carburetor Refer to "CARBURETOR" section.
Camshaft Refer to "CAMSHAFTS" section.
1Bolt 2
2* Bolt 4 Refer to NOTE.
3 Cylinder head 1
4 Gasket 1
5 Timing chain guide (exhaust side) 1

5-53
ENGINE REMOVAL
ENGINE REMOVAL
REMOVING THE ENGINE
Order Part name Q'ty Remarks
Hold the machine by placing the suitable stand
under the frame.Refer to "HANDLING NOTE".
Drain the engine oil.Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Seat and fuel tank Refer to "REMOVING THE SEAT, FUEL
TANK AND SIDE COVERS" section in the
CHAPTER 3.
Radiator Refer to "RADIATOR" section.
Exhaust pipe and silencer Refer to "REMOVING THE EXHAUST PIPE
AND SILENCER" section in the CHAPTER 3.
Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section.
Clutch cable and guide Disconnect at the engine side.
Shift pedalRefer to "AC MAGNETO AND STARTER
CLUTCH" section.
Rear shock absorberRefer to "REAR SHOCK ABSORBER" sec-
tion in the CHAPTER 6.
Carburetor Refer to "CARBURETOR" section.
Cylinder head breather hose Refer to "CAMSHAFTS" section.
Oil hose and oil tank breather hose Refer to "OIL PUMP" section.