2016 YAMAHA YZ450F Owners Manual

6
COOLING SYSTEM
RADIATOR....................................................................................................... 6-1
HANDLING NOTE ...................................................................................... 6-3
CHECKING THE RADIATOR ..................................................................... 6-3
WATER PUMP.................................................................................................. 6-4
REMOVING THE OIL SEAL ....................................................................... 6-5
CHECKING THE WATER PUMP ............................................................... 6-5
CHECKING THE BEARING....................................................................... 6-5
INSTALLING THE OIL SEAL..................................................................... 6-5
ASSEMBLING THE WATER PUMP........................................................... 6-5

RADIATOR
6-1
EASB111293
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, service engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EASB111294
RADIATOR
Removing the radiator
Order Part name Q’ty Remarks
CoolantDrain.
Refer to “CHANGING THE COOLANT” on
page 3-8.
Seat Refer to “GENERAL CHASSIS” on page 4-1.
Side cover (left/right) Refer to “GENERAL CHASSIS” on page 4-1.
Air scoop (left / right) Refer to “GENERAL CHASSIS” on page 4-1.
Fuel tank Refer to “FUEL TANK” on page 7-1.
Air filter case Refer to “THROTTLE BODY” on page 7-5.
1 Radiator guard 2
2 Radiator hose clamp 8 Loosen.
3 Right radiator 1
11
12
New
New
New
LS
LS

RADIATOR
6-2
4 Radiator hose 2 1
5 Radiator hose 3 1
6 Radiator hose 4 1
7 Radiator pipe 2 1
8 Radiator breather hose 1
9 Left radiator 1
10 Radiator hose 1 1
11 Radiator pipe 1 1
12 Coolant temperature sensor 1
For installation, reverse the removal proce-
dure.
Removing the radiator
Order Part name Q’ty Remarks
11
12
New
New
New
LS
LS

RADIATOR
6-3
EASB111295HANDLING NOTEEWA
WARNING
If coolant seems hot, do not remove the ra-
diator cap.
EASB111296CHECKING THE RADIATOR
1. Check:
• Radiator fins “1”
Obstructions  Clean.
Apply compressed air to the rear of the radi-
ator.
Damage  Repair or replace.
TIP
Correct any flattened fins with a thin, flat-head
screwdriver.
2. Check:
• Radiator hoses
• Radiator pipes
Crack/damage  Replace.

WATER PUMP
6-4
EASB111297
WATER PUMP
Removing the water pump
Order Part name Q’ty Remarks
CoolantDrain.
Refer to “CHANGING THE COOLANT” on
page 3-8.
Engine oilDrain.
Refer to “CHANGING THE ENGINE OIL” on
page 3-15.
Right crankcase cover Refer to “CLUTCH” on page 5-38.
1 Water pump housing 1
2 Dowel pin 2
3Gasket 1
4Collar 1
5Pin 1
6 Impeller shaft assembly 1
7 Oil seal 1
8 Bearing 1
9 Oil seal 1
For installation, reverse the removal proce-
dure.
LS
LS
7
6
2
2
3
1
854
New
New
New
E
9
New
E
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.

WATER PUMP
6-5
EASB111298REMOVING THE OIL SEAL
TIP
• Remove the oil seal when the coolant level
changes frequently more than usual, coolant
has discolored, or engine oil has become
milky.
• Do not use the removed oil seal.
1. Remove:
• Oil seals “1”
EASB111299CHECKING THE WATER PUMP
1. Check:
• Water pump housing cover
• Impeller shaft
Cracks/damage/wear  Replace.
EASB111300CHECKING THE BEARING
1. Check:
• Bearing
Rotate the inner race with your finger.
Rough spot/seizure  Replace.
EASB111301INSTALLING THE OIL SEAL
1. Install:
• Oil seals “1”
TIP
• Apply the lithium-soap-based grease on the
oil seal lip.
• Install the oil seal with its manufacture’s
marks or numbers facing the right crankcase
cover “2”.2. Install:
• Bearing “1”
TIP
Install the bearing by pressing its outer race
parallel.
EASB111302ASSEMBLING THE WATER PUMP
1. Install:
• Impeller shaft assembly “1”
•Pin “2”
• Collar “3”
• Circlip “4”
TIP
• Take care so that the oil seal lip is not dam-
aged or the spring does not slip off its posi-
tion.
• When installing the impeller shaft, apply the
engine oil to the oil seal lip, the bearing, and
the impeller shaft.
1 1
New
1 1New
New
LS
LS2
New
4
1
23New
E

WATER PUMP
6-6
2. Install:
• Dowel pin “1”
• Gasket “2”
3. Install:
• Water pump housing “1”
• Water pump housing bolt “2”
• Washer “3”
• Coolant drain bolt “4”Water pump housing bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Coolant drain bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
New
21
1New
T R..
New
T R..
2
2
43 1
New

WATER PUMP
6-7