Yamaha YZ250 2022, Owner'S Service Manual, Page: 213 / 274

WATER PUMP
6-6
EAM30494
DISASSEMBLING THE WATER PUMP
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 seal “1”
EAM30259
CHECKING THE WATER PUMP
1. Check:
• Water pump housing cover
•
Impeller shaft
• Impeller
Cracks/damage/wear

Replace.
2. Check:
•
Bearing “1”
Rotate the inner race with your finger.
Rough spot/seizure

Replace.
EAM30262
ASSEMBLING THE WATER PUMP
1. Install:
• Oil seal “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 crankcase cover (right).
2. Install:
• Bearing “1”
TIP
Install the bearing by pressing its outer race par-
allel.
3. Install:
• Impeller shaft assembly “1”
•
Washer “2”
• Circlip
•
Impeller “3”
TIP
• Take care so that the oil seal lip is not dam-
aged or the spring does not slip off its position.
• When installing the impeller shaft, apply the
lithium-soap-based grease on the oil seal lip
and impeller shaft. And install the shaft while
turning it.
• Hold the impeller shaft on its width across the
flats “a” with spanners, etc. and install the im-
peller.
Ne w
Impeller
14 N·m (1.4 kgf·m, 10 lb·ft)
1
1
Ne w
T
R
.
.