2001 YAMAHA YZ250F water pump

4 - 58
ENG
OIL FILTER ELEMENT, WATER PUMP AND RIGHT
CRANKCASE COVER
EC444200
Impeller shaft
1. Inspect:
lImpeller shaft 1
Bend/wear/damage ® Replace.
Fur deposits ® Clean.
EC444300
Impeller shaft gear
1. Inspect:
lGear teeth a
Wear/damage ® Replace.
EC4H4600
Bearing
1. Inspect:
lBearing
Rotate inner race with a finger.
Rough spot/seizure ® Replace.
EC444400
Oil seal
1. Inspect:
lOil seal 1
Wear/damage ® Replace.
ASSEMBLY AND INSTALLATION
Oil seal
1. Install:
lOil seal 1
NOTE:
lApply the lithium soap base grease on the oil
seal lip.
lInstall the oil seal with its manufacture’s
marks or numbers facing the right crankcase
cover 2.

4 - 59
ENG
OIL FILTER ELEMENT, WATER PUMP AND RIGHT
CRANKCASE COVER
2. Install:
lBearing 1
NOTE:
Install the bearing by pressing its outer race
parallel.
Impeller shaft
1. Install:
lImpeller shaft 1
lWasher 2
lImpeller 3
NOTE:
lTake care so that the oil seal lip is not dam-
aged or the spring does not slip off its posi-
tion.
lWhen installing the impeller shaft, apply the
lithium soap base grease on the oil seal lip
and impeller shaft. And install the shaft while
turning it.
lHold the impeller shaft on its width across
the flats a with spanners, etc. and remove
the impeller.
T R..14 Nm (1.4 m · kg, 10 ft · lb)
Right crankcase cover
1. Install:
lDowel pin 1
lO-ring 2
lCollar 3
lGasket 4
NOTE:
Apply the lithium soap base grease on the O-
ring.

4 - 60
ENG
OIL FILTER ELEMENT, WATER PUMP AND RIGHT
CRANKCASE COVER
2. Install:
lRight crankcase cover 1
lBolt (right crankcase cover) 2
NOTE:
lApply the engine oil on the impeller shaft
end.
lMesh the impeller shaft gear 3 with primary
drive gear 4.
lTighten the bolts in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Kickstarter crank
1. Install:
lKickstarter crank 1
lWasher 2
lBolt (kickstarter crank) 3
NOTE:
Install the kickstarter crank so that the kick-
starter crank is as vertical as possible with the
distance a between the kickstarter crank and
the frame being 8 mm (0.31 in) or more.
2. Install:
lOil hose 1
lBolt (oil hose) 2
T R..33 Nm (3.3 m · kg, 24 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
3. Install:
lCopper washer 1
lOil delivery pipe 2
lUnion bolt (M8) 3
lUnion bolt (M10) 4
T R..18 Nm (1.8 m · kg, 13 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)

4 - 61
ENG
OIL FILTER ELEMENT, WATER PUMP AND RIGHT
CRANKCASE COVER
Water pump housing
1. Install:
lDowel pin 1
lO-ring 2
NOTE:
Apply the lithium soap base grease on the O-
ring.
2. Install:
lWater pump housing 1
lBolt (water pump housing) 2
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Oil filter element
1. Install:
lOil filter element 1
lO-ring 2
lOil filter element cover 3
lBolt (oil filter element cover)
NOTE:
Apply the lithium soap base grease on the O-
ring.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 62
ENGBALANCER
BALANCER
Extent of removal:1 Balancer shaft drive gear2 Balancer shaft
Extent of removal Order Part name Q’ty Remarks
BALANCER REMOVAL
Preparation for removal Primary driven gear Refer to “CLUTCH” section.
Right crankcase cover Refer to “OIL FILTER ELEMENT,
WATER PUMP AND RIGHT CRANK-
CASE COVER” section.
Stator Refer to “CDI MAGNETO” section.
1 Nut (primary drive gear) 1
Refer to “REMOVAL POINTS”.
2 Nut (balancer shaft driven gear) 1
3 Lock washer 1
4 Primary drive gear 1
5 Balancer shaft drive gear 1
6 Lock washer 1
7 Balancer shaft driven gear 1
8 Balancer shaft 1 Refer to “REMOVAL POINTS”.
2
1
2

4 - 65
ENGOIL PUMP
OIL PUMP
Extent of removal:1 Oil pump removal2 Oil pump disassembly
Extent of removal Order Part name Q’ty Remarks
OIL PUMP REMOVAL AND DIS-
ASSEMBLY
Preparation for removal Primary driven gear Refer to “CLUTCH” section.
Right crankcase cover Refer to “OIL FILTER ELEMENT,
WATER PUMP AND RIGHT CRANK-
CASE COVER” section.
1 Circlip 1
2 Washer 1
3 Oil pump drive gear 1
4 Oil pump assembly 1
5 Outer rotor 2 1
6 Circlip 1
7 Inner rotor 2 1
8 Dowel pin 1
9 Oil pump cover 1
10 Outer rotor 1 1
11Inner rotor 1
1
2
1