2001 YAMAHA YZ125LC oil

4-44
ENG
KICK AXLE, SHIFT SHAFT AND PRIMARY DRIVE
GEAR
4. Hook:
9Torsion spring 1
NOTE:
Turn the torsion spring clockwise and hook into
the proper hole ain the crankcase.
EC4C5402
Kick idle gear
1. Install:
9Circlip 1
9Kick idle gear 2
9Plain washer 3
NOTE:
9Apply the transmission oil on the kick idle gear
inner circumference.
9Install the kick idle gear with its depressed side
atoward you.
EC4C5502
Primary drive gear
1. Install:
9Primary drive gear 1
9Bolt 2
NOTE:
Temporarily tighten the bolt at this point.
2. Install:
9Primary driven gear
Refer to “CLUTCH AND PRIMARY DRI-
VEN GEAR” section.
3. Tighten:
9Bolt (primary drive gear) 1
NOTE:
Place an aluminum plate abetween the teeth of
the primary drive gear 2and driven gear 3.
4. Install:
9Dowel pin 1
9Gasket [crankcase cover (right)] 2
55 Nm (5.5 m•kg, 40 ft•lb)
5MV-9-30-4C 6/19/00 1:41 PM Page 14

4-48
ENGYPVS GOVERNOR
2. Install:
9Ball 1
9Retainer 2
To governor shaft 3.
NOTE:
Apply the transmission oil on the retainer and
ball.
3. Install:
9Dowel pin 1
NOTE:
9While compressing the spring, install the dowel
pin.
9Make sure the dowel pin fits into the groove a
in the retainer.
4. Install:
9Governor assembly 1
NOTE:
Align the groove ain the governor with the fork
band set the governor in the crankcase cover.
5MV-9-30-4C 6/19/00 1:42 PM Page 22

4-49
ENGWATER PUMP
Extent of removal Order Part name Q’ty Remarks
WATER PUMP DISASSEMBLY
Preparation for Crankcase cover (right)
Refer to “KICK AXLE, SHIFT SHAFT AND
removalPRIMARY DRIVE GEAR” section.
1 Water pump housing cover 1
2 Impeller 1
3 Plain washer 1 Refer to “REMOVAL POINTS”.
4 Impeller shaft 1
5 Bearing 1
6 Oil seal 2Refer to “REMOVAL POINTS”.
EC4G0000
WATER PUMP
1
2
Extent of removal:1Impeller shaft removal2Oil seal removal
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14 Nm (1.4 m•kg, 10 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
5MV-9-30-4C 6/19/00 1:42 PM Page 24

4-50
ENGWATER PUMP
EC4G3000
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
9Impeller 1
9Plain washer 2
9Impeller shaft 3
NOTE:
Hold the impeller shaft on its width across the
flats awith spanners, etc. and remove the im-
peller.
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, discoloration
of coolant, or milky transmission oil.
1. Remove:
9Bearing 1
2. Remove:
9Oil seal 1
EC4G4000
INSPECTIONEC444200
Impeller shaft
1. Inspect:
9Impeller shaft 1
Bend/Wear/Damage ÕReplace.
Fur deposits ÕClean.
5MV-9-30-4C 6/19/00 1:42 PM Page 26

4-51
ENGWATER PUMP
EC444300
Impeller shaft gear
1. Inspect:
9Gear teeth a
Wear/Damage ÕReplace.
EC4H4600
Bearing
1. Inspect:
9Bearing 1
Rotate inner race with a finger.
Rough spot/Seizure ÕReplace.
EC444400
Oil seal
1. Inspect:
9Oil seal 1
Wear/Damage ÕReplace.
EC4G5000
ASSEMBLY AND INSTALLATION
EC4G5111
Oil seal
1. Install:
9Oil seal 1
NOTE:
9Apply the lithium soap base grease on the oil
seal lip.
9Install the oil seal with its manufacture's marks
or numbers facing the crankcase cover (right)
2.
2. Install:
9Bearing 1
NOTE:
Install the bearing by pressing its outer race par-
allel.
5MV-9-30-4C 6/19/00 1:42 PM Page 28

4-52
ENGWATER PUMP
EC4G5220
Impeller shaft
1. Install:
9Impeller shaft 1
NOTE:
9Take care so that the oil seal lip is not dam-
aged or the spring does not slip off its position.
9When installing the impeller shaft, apply the
lithium soap base grease on the oil seal lip and
impeller shaft. And install the shaft while turn-
ing it.
2. Install:
9Plain washer 1
9Impeller 2
NOTE:
Hold the impeller shaft on its width across the
flats awith spanners, etc. and install the im-
peller.
3. Install:
9Dowel pin 1
9Gasket (water pump housing cover) 2
4. Install:
9Water pump housing cover 1
9Bolt (water pump housing cover) 2
9Copper washer (coolant drain bolt) 3
9Coolant drain bolt 4
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
14 Nm (1.4 m•kg, 10 ft•lb)
5MV-9-30-4C 6/19/00 1:42 PM Page 30

4-62
ENGCRANKCASE AND CRANKSHAFT
Extent of removal Order Part name Q’ty Remarks
CRANKCASE AND CRANKSHAFT
REMOVAL
Preparation for Engine Refer to “ENGINE REMOVAL”section.
removal Piston Refer to “
CYLINDER HEAD, CYLINDER
AND PISTON
” section.
Primary drive gear
Kick idle gearRefer to “
KICK AXLE, SHIFT SHAFT AND
Stopper leverPRIMARY DRIVE GEAR”section.
Rotor and stator Refer to “CDI MAGNETO” section.
1 Segment 1 Refer to “REMOVAL POINTS”.
2 Bolt [L=50 mm (1.97 in)] 4
3 Bolt [L=60 mm (2.36 in)] 6
4 Bolt [L=70 mm (2.76 in)] 2
5 Holder 1
6 Crankcase (right) 1 Use special tool.
7 Crankcase (left) 1 Refer to “REMOVAL POINTS”.
8 Crankshaft 1 Use special tool.
Refer to “REMOVAL POINTS”.
9 Oil seal 2
10 Bearing 2 Refer to “REMOVAL POINTS”.
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EC4N0000
12
3
Extent of removal:1Crankcase separation2Crankshaft removal
3Crankshaft bearing removal
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30 Nm (3.0 m•kg, 22 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
20 Nm (2.0 m•kg, 14 ft•lb)
14 Nm (1.4 m•kg, 10 ft•lb)
5MV-9-30-4D 6/19/00 1:39 PM Page 12

4-65
ENGCRANKCASE AND CRANKSHAFT
Standard
Runout 0.03 mm 0.05 mm
limit: (0.0012 in) (0.0020 in)
Small end 0.8~1.0 mm 2.0 mm
free play: (0.031~0.039 in) (0.08 in)
Side 0.20~0.70 mm
—
clearance: (0.008~0.028in)
Crank 55.90~55.95 mm
—
width: (2.201~2.203 in)
2. Inspect:
9Bearings 1
Rotate inner race with a finger.
Rough spot/Seizure ÕReplace.
3. Inspect:
9Oil seal 1
Damage ÕReplace.
EC4N4202
Crankshaft
1. Measure:
9Runout limit a
9Small end free play limit b
9Connecting rod big end side clearance c
9Crank width d
Out of specification ÕReplace.
Use the dial gauge and a thickness gauge.
EC4N5000
ASSEMBLY AND INSTALLATION
EC4N5300
Crankshaft bearing
1. Install:
9Bearing 1
To crankcase (left and right).
NOTE:
Install the bearing by pressing its outer race
parallel.
Dial gauge:
YU-3097/90890-01252
5MV-9-30-4D 6/19/00 1:39 PM Page 18