engine YAMAHA WR 250F 2001 Notices Demploi (in French)

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ENGBALANCER
ASSEMBLY AND INSTALLATION
Balancer shaft, balancer shaft drive gear
and balancer shaft driven gear
1. Install:
lBalancer shaft 1
NOTE:
lApply the engine oil on the bearing.
lWhen installing the balancer shaft, align the
center a of the balancer shaft weight along
the line connecting the centers of the crank-
shaft and balancer shaft.
2. Install:
lBalancer shaft driven gear 1
NOTE:
Install the balancer shaft driven gear onto the
balancer shaft while aligning the punch mark
a on the balancer shaft driven gear with the
lower spline b on the balancer shaft end.
3. Install:
lBalancer shaft drive gear 1
NOTE:
lAlign the punched mark a on the balancer
shaft drive gear with the punched mark b on
the balancer shaft driven gear 2.
lAlign the punched mark c on the balancer
shaft drive gear with the lower spline d on
the crankshaft end.
4. Install:
lLock washer 1
lNut (balancer shaft driven gear) 2
lPrimary drive gear 3
lNut (primary drive gear) 4
NOTE:
lInstall the primary drive gear with its stepped
side a facing the engine.
lPlace an aluminum plate b between the
teeth of the balancer shaft drive gear 5 and
driven gear 6.
5. Bend the lock washer tab.
T R..50 Nm (5.0 m · kg, 3.6 ft · lb)
T R..75 Nm (7.5 m · kg, 54 ft · lb)

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ENGOIL PUMP
ASSEMBLY AND INSTALLATION
Oil pump
1. Install:
lOil pump drive shaft 1
lWasher 2
lDowel pin 3
lInner rotor 1 4
NOTE:
lApply the engine oil on the oil pump drive
shaft and inner rotor 1.
lFit the dowel pin into the groove in the inner
rotor 1.
2. Install:
lOuter rotor 1 1
NOTE:
Apply the engine oil on the outer rotor 1.
3. Install:
lOil pump cover 1
lScrew (oil pump cover) 2
lDowel pin 3
lInner rotor 2 4
lCirclip 5
NOTE:
lApply the engine oil on the inner rotor 2.
lFit the dowel pin into the groove in the inner
rotor 2.
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)

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ENG
4. Install:
lOuter rotor 2 1
lDowel pin 2
lOil pump assembly 3
lBolt (oil pump assembly)
[L = 25 mm (0.94 in)] 4
lBolt (oil pump assembly)
[L = 30 mm (1.18 in)] 5
NOTE:
Apply the engine oil on the outer rotor 2.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
5. Install:
lOil pump drive gear 1
lWasher 2
lCirclip 3
NOTE:
Apply the engine oil on the oil pump drive gear
inner circumference.
OIL PUMP

4 - 75
ENGKICK SHAFT AND SHIFT SHAFT
EC4B5111
Stopper lever
1. Install:
lTorsion spring 1
lStopper lever 2
lBolt (stopper lever) 3
NOTE:
Align the stopper lever roller with the slot on
segment.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Shift guide and shift lever assembly
1. Install:
lSpring 1
lPawl pin 2
lPawl 3
To shift lever 4.
NOTE:
Apply the engine oil on the spring, pawl pin
and pawl.
2. Install:
lShift lever assembly 1
To shift guide 2.
3. Install:
lShift lever assembly 1
lShift guide 2
NOTE:
lThe shift lever assembly is installed at the
same time as the shift guide.
lApply the engine oil on the bolt (segment)
shaft.

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ENGKICK SHAFT AND SHIFT SHAFT
4. Install:
lBolt (shift guide) 1
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Shift shaft
1. Install:
lRoller 1
lCollar 2
lTorsion spring 3
lShift shaft 4
NOTE:
Apply the engine oil on the roller and shift
shaft.
2. Install:
lShift pedal 1
lBolt (shift pedal) 2
NOTE:
When installing the shift pedal onto the shift
shaft, be sure that the center of the shift pedal
is about 2 mm a above the top of the footrest.
Kick shaft assembly
1. Install:
lKick gear 1
lWasher 2
lCirclip 3
lRatchet wheel 4
lSpring 5
lWasher 6
lCirclip 7
To kick shaft 8.
NOTE:
lApply the molybdenum disulfide oil on the
kick gear inner circumference.
lAlign the punch mark a on the ratchet wheel
with the punch mark b on the kick shaft.

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ENGKICK SHAFT AND SHIFT SHAFT
2. Install:
lTorsion spring 1
To kick shaft 2.
NOTE:
Make sure the stopper a of the torsion spring
fits into the hole b on the kick shaft.
3. Install:
lSpring guide 1
NOTE:
Slide the spring guide into the kick shaft, make
sure the groove a in the spring guide fits on
the stopper of the torsion spring.
4. Install:
lKick shaft assembly 1
lWasher 2
NOTE:
lApply the engine oil on the kick shaft.
lSlide the kick shaft assembly into the crank-
case, make sure the kick shaft stopper a fit
into their home position 3.
5. Hook:
lTorsion spring 1
NOTE:
Turn the torsion spring clockwise and hook
into the proper hole a in the crankcase.
Kick idle gear
1. Install:
lKick idle gear 1
lWasher 2
lCirclip 3
NOTE:
lApply the engine oil on the kick idle gear
inner circumference.
lInstall the kick idle gear with its depressed
side a toward you.

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ENGCDI MAGNETO
EC4L0000
CDI MAGNETO
Extent of removal:1 CDI magneto removal
Extent of removal Order Part name Q’ty Remarks
CDI MAGNETO REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Bolt (left radiator) Refer to “RADIATOR” section.
Disconnect the CDI magneto lead.
Shift pedal Refer to “KICK SHAFT AND SHIFT
SHAFT” section.
1 Left engine guard 1
2 Left crankcase cover 1
3 Nut (rotor) 1 Use special tool.
Refer to “REMOVAL POINTS”.
4 Rotor 1
5 Stator 1
6Woodruff key
1
1

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ENGCDI MAGNETO
4. Connect:
lCDI magneto lead
Refer to “CABLE ROUTING DIA-
GRAM” section in the CHAPTER 2.
5. Install:
lDowel pin
lGasket (left crankcase cover)
lLeft crankcase cover 1
lHose guide (cylinder head breather
hose) 2
lBolt (left crankcase cover) 3
NOTE:
Tighten the screws in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
6. Install:
lLeft engine guard 1
lHose holder (cylinder head breather
hose) 2
lBolt (left engine guard) 3
lCylinder head breather hose 4
3
2
14
3
T R..23 Nm (2.3 m · kg, 17 ft · lb)

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ENGENGINE REMOVAL
EC4M0000
ENGINE REMOVAL
Extent of removal Order Part name Q’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the
suitable stand under the frame.
WARNING
Support the machine securely so there is nodanger of it falling over.
Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR” section.
Exhaust pipe and silencer Refer to “EXHAUST PIPE AND
SILENCER” section.
Clutch cable Disconnect at engine side.
Decompression cable and guide Disconnect at engine side.
Radiator Refer to “RADIATOR” section.
Shift pedal Refer to “KICK SHAFT AND SHIFT
SHAFT” section.
Cylinder head breather hose and
oil tank breather hoseRefer to “CAMSHAFTS” section.
Drain the engine oil Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.

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ENGENGINE REMOVAL
Extent of removal:1 Engine removal
Extent of removal Order Part name Q’ty Remarks
Spark plug cap
Disconnect the CDI magneto lead.
Right engine guard
1 Neutral switch 1
2 Bolt (oil hose) 2
3 Drive chain sprocket cover 1
4 Nut (drive sprocket) 1
Refer to “REMOVAL POINTS”. 5 Lock washer 1
6 Drive sprocket 1
7 Clip 1
8 Bolt (brake pedal) 1
9 Brake pedal 1
10 Upper engine bracket 2
11 Lower engine bracket 2
12 Engine mounting bolt 3
13 Pivot shaft 1
Refer to “REMOVAL POINTS”.
14Engine
1
1