2002 YAMAHA WR 400F water pump

ENG
4 - 64
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
Extent of removal Order Part name Q’ty Remarks
7 Oil hose 1
8 Kick crank 1
9 Crankcase cover (right) 1
10 Gasket 1
11 Dowel pin/O-ring 4/2
12 Impeller 1
Refer to “REMOVAL POINTS”. 13 Plain washer 1
14 Impeller shaft 1
15 Oil seal 1 1
16 Oil seal 2 1
17 Bearing 1
2
3
2

4 - 65
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
Impeller 1
Plain washer 2
Impeller shaft 3
NOTE:
Hold the impeller shaft on its width across the
flats a with spanners, etc. and remove the
impeller.
EC4G3210
Oil seal
NOTE:
It is not necessary to disassemble the water
pump, unless there is an abnormality such as
excessive change in coolant level, discolora-
tion of coolant, or milky transmission oil.
1. Remove:
Bearing 1
Oil seal 2
INSPECTION
EC444200
Impeller shaft
1. Inspect:
Impeller shaft 1
Bend/wear/damage → Replace.
Fur deposits → Clean.

4 - 66
ENG
EC4H4600
Bearing
1. Inspect:
Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
EC444400
Oil seal
1. Inspect:
Oil seal
Wear/damage → Replace.
ASSEMBLY AND INSTALLATION
EC4G5110
Oil seal
1. Install:
Oil seal 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
Install the oil seal with its manufacture’s
marks or numbers facing inward.
Bearing
1. Install:
Bearing 1
NOTE:
Install the bearing by pressing its outer race
parallel.
New
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)

4 - 67
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
EC4G5220
Impeller shaft
1. Install:
Impeller shaft 1
Plain washer 2
Impeller 3
NOTE:
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 on the oil seal lip, bearing 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
impeller.
T R..14 Nm (1.4 m · kg, 10 ft · lb)
Crankcase cover (right)
1. Install:
Dowel pin 1
O-ring 2
Collar 3
Gasket 4 New
2. Install:
Crankcase cover (right) 1
Bolt
NOTE:
Apply the engine oil on the impeller shaft
end.
When installing the crankcase cover onto the
crankcase, be sure that the impeller shaft
end 2 aligns with the balancer end slot 3.
Tighten the bolts in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 68
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
Kick crank
1. Install:
Kick crank 1
Plain washer
Bolt (kick crank)
NOTE:
Install the kick crank so that the kick crank is
as vertical as possible with the distance a
between the kick crank and the frame being
5 mm (0.20 in) or more.
T R..33 Nm (3.3 m · kg, 24 ft · lb)
2. Install:
Oil hose 1
Bolt (oil hose) 2
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
3. Install:
Copper washer 1
Oil delivery pipe 2
Union bolt (M8) 3
Union bolt (M10) 4
New
T R..18 Nm (1.8 m · kg, 13 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
Water pump housing
1. Install:
Dowel pin 1
O-ring 2 New

4 - 69
ENG
2. Install:
Water pump housing 1
Bolt (water pump housing) 2
Plain washer 3
Coolant drain bolt 4
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
3. Install:
O-ring
Coolant pipe 1
Bolt (coolant pipe) 2
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Oil filter
1. Install:
Oil filter 1
O-ring 2
Oil filter cover 3
Bolt (oil filter cover)
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)

ENG
4 - 70
BALANCER
BALANCER
BALANCER
Extent of removal:1 Balancer drive gear2 Balancer
Extent of removal Order Part name Q’ty Remarks
BALANCER REMOVAL
Preparation for removal Clutch housing Refer to “CLUTCH” section.
Crankcase cover (right)Refer to “OIL FILTER, WATER PUMP AND
CRANKCASE COVER (RIGHT)” section.
Stator Refer to “CDI MAGNETO” section.
1 Nut (primary drive gear) 1
Refer to “REMOVAL POINTS”.
2 Nut (balancer) 1
3 Lock washer 1
4 Primary drive gear 1
5 Balancer drive gear 1
6 Lock washer 1
7 Balancer driven gear 1
8 Balancer 1 Refer to “REMOVAL POINTS”.
2
1
2

ENG
4 - 73
OIL PUMP
OIL PUMP
OIL PUMP
Extent of removal:1 Oil pump removal2 Oil pump disassembly
Extent of removal Order Part name Q’ty Remarks
Preparation for removalOIL PUMP REMOVAL AND DIS-
ASSEMBLY
Clutch housing Refer to “CLUTCH” section.
Crankcase cover (right) Refer to “OIL FILTER, WATER PUMP
AND CRANKCASE COVER (RIGHT)”
section.
1 Circlip 1
2 Plate washer 1
3 Oil pump drive gear 1
4 Oil pump assembly 1
5 Dowel pin 1
6 Outer rotor 2 1
7 Circlip 1
8 Inner rotor 2 1
9 Pin 1
10 Oil pump cover 1
11 Outer rotor 1 1
12Inner rotor 1
1
2
1