2000 YAMAHA WR 400F oil

4 - 52
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
EC4G3000
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
lImpeller 1
lPlain washer 2
lImpeller 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:
lBearing 1
2. Remove:
lOil seal 1
EC4G4000
INSPECTION
EC444200
Impeller shaft
1. Inspect:
lImpeller shaft 1
Bend/wear/damage ® Replace.
Fur deposits ® Clean.

4 - 53
ENG
EC4H4600
Bearing
1. Inspect:
lBearing
Rotate inner race with a finger.
Rough spot/seizure ® Replace.
EC444400
Oil seal
1. Inspect:
lOil seal
Wear/damage ® Replace.
EC4G5000
ASSEMBLY AND INSTALLATION
EC4G5110
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 inward.
Bearing
1. Install:
lBearing 1
NOTE:
Install the bearing by pressing its outer race
parallel.
New
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)

4 - 54
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
EC4G5220
Impeller shaft
1. Install:
lImpeller shaft 1
lPlain washer 2
lImpeller shaft 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
engine oil 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.
Crankcase cover (right)
1. Install:
lDowel pin 1
lO-ring 2
lCollar 3
lGasket 4 New
2. Install:
lCrankcase cover (right) 1
lBolt
NOTE:
lWhen installing the crankcase cover onto the
crankcase, be sure that the impeller shaft
end 2 aligns with the balancer end slot 3.
lTighten the bolts in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 55
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
Kick crank
1. Install:
lKick crank 1
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:
lOil hose 1
lBolt (oil hose) 2
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)
Water pump housing
1. Install:
lPin 1
lO-ring 2 New
2. Install:
lWater pump housing 1
lBolt (water pump housing) 2
lPlain washer 3
lCoolant 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)

ENG
4 - 56
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 Straight key 1
7 Lock washer 1
8 Balancer driven gear 1
9Balancer
1
2
1
2

ENG
4 - 59
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

ENG
4 - 60
Extent of removal Order Part name Q’ty Remarks
13 Pin 1
14 Washer 1
15 Oil pump drive shaft 1
16 Rotor housing 1
2
OIL PUMP

4 - 61
ENG

OIL PUMP
INSPECTION
Oil pump
1. Inspect:
l
Oil pump drive gear
l
Oil pump driven gear
l
Rotor housing
l
Oil pump cover
Cracks/wear/damage
®
Replace.
2. Measure:
l
Tip clearance
a

Between the inner rotor
1
and the
outer rotor
2
.
l
Side clearance
b

Between the outer rotor
2
and the rotor
housing
3
.
Out of specification
®
Replace the oil
pump.
Tip clearance
a
:
0.07 ~ 0.12 mm (0.0028 ~ 0.0047 in)
: 0.15 mm (0.006 in)
Tip clearance
b
:
0.09 ~ 0.15 mm (0.0035 ~ 0.0059 in)
: 0.22 mm (0.009 in)
Side clearance
c
:
0.03 ~ 0.08 mm (0.0012 ~ 0.0031 in)
: 0.15 mm (0.006 in)
3. Check:
l
Unsmooth
®
Repeat steps #1 and #2
or replace the defective parts.
ASSEMBLY AND INSTALLATION
Oil pump
1. Install:
l
Oil pump drive shaft
1

l
Washer
2

l
Pin
3

l
Inner rotor 1
4

NOTE:

Fit the pin into the groove in the inner rotor 1.