2003 YAMAHA WR 250F fuel

3 - 131
INSP
ADJ
REPLACING THE HEADLIGHT
BULBS
1. Remove:
Headlight
Refer to “SEAT, FUEL TANK
AND SIDE COVERS” section
in the CHAPTER 4.
2. Remove:
Headlight bulb holder cover
1
3. Detach:
Headlight bulb holder
1
4. Remove:
Headlight bulb
2
WARNING
Since the headlight bulb gets
extremely hot, keep flammable
products and your hands away
from the bulb unit it has cooled
down.
5. Install:
Headlight bulb
Secure the new headlight bulb
with the headlight bulb holder.
CAUTION:
Avoid touching the glass part of
the headlight bulb to keep it free
form oil, otherwise the transpar-
ency of the glass, the life of the
bulb and the luminous flux will be
adversely affected. If the headlight
bulb gets soiled, thoroughly clean
it with a cloth moistened with alco-
hol or lacquer thinner.
6. Attach:
Headlight bulb holder
7. Install:
Headlight bulb holder cover
8. Install:
Headlight
Refer to “SEAT, FUEL TANK
AND SIDE COVERS” section
in the CHAPTER 4.
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
New
REMPLACER LES AMPOULES DU
PHARE
1. Déposer:
Phare
Se reporter à la section “SELLE,
RESERVOIR DE CARBURANT
ET CACHES LATERAUX” au
CHAPITRE 4.
2. Déposer:
Cache de fixation d’ampoule de
phare 1
3. Détacher:
Fixation d’ampoule de phare 1
4. Déposer:
Ampoule de phare 2
AVERTISSEMENT
L’ampoule de phare chauffant consi-
dérablement, écarter les produits
inflammables et les mains jusqu’à
refroidissement de l’ensemble
ampoule.
5. Installer:
Ampoule de phare
Poser soigneusement la nouvelle
ampoule de phare dans le porte
ampoule de phare.
ATTENTION:
Eviter de toucher la partie en verre de
l’ampoule afin d’éviter tout contact
avec de l’huile, sinon la transparence
du verre, la durée de vie de l’ampoule
et le rayonnement lumineux, pour-
raient être diminués. Si l’ampoule de
phare est sale, la nettoyer à fond avec
un chiffon humecté d’alcool ou d’un
dissolvant cellulosique.
6. Attacher:
Fixation d’ampoule de phare
7. Installer:
Cache de fixation d’ampoule de
phare
8. Installer:
Phare
Se reporter à la section “SELLE,
RESERVOIR DE CARBURANT
ET CACHES LATERAUX” au
CHAPITRE 4.
T R..7 Nm (0,7 m · kg, 5,1 ft · lb)
New
ELECTRICAL
PARTIE ELECTRIQUE

4 - 1
ENGSEAT, FUEL TANK AND SIDE COVERS
EC400000
ENGINE
SEAT, FUEL TANK AND SIDE COVERS
Extent of removal:
1 Seat removal
2 Fuel tank removal
3 Side covers removal
4 Headlight removal
Extent of removal Order Part name Q’ty Remarks
SEAT, FUEL TANK AND SIDE COVERS
REMOVAL
Preparation for removal Turn the fuel cock to “OFF”.
Disconnect the fuel hose.
1Seat 1
2 Air scoop (left and right) 2
3 Fitting band 1 Remove on fuel tank side.
4 Bolt (fuel tank) 2
5 Fuel tank 1
6 Left side cover 1
Refer to “REMOVAL POINTS”.
7 Right side cover 1
8 Headlight coupler 1
9 Headlight 1
2
13
4
3

4 - 5
ENGSEAT, FUEL TANK AND SIDE COVERS
REMOVAL POINTS
Side cover
1. Remove:
Bolt (side cover)
Left side cover
1
Right side cover
2
NOTE:Draw the side cover downward to
remove it because its claws
a are
inserted in the air filter case.
POINTS DE DEPOSE
Cache latéral
1. Déposer:
Boulon (cache latéral)
Cache latéral gauche 1
Cache latéral droit 2
N.B.:
Tirer le cache latéral vers le bas pour
l’enlever car les griffes a sont insérées
dans le carter de filtre à air.
SELLE, RESERVOIR DE CARBURANT ET CACHES LATERAUX

4 - 7
ENGEXHAUST PIPE AND SILENCER
EC4S0000
EXHAUST PIPE AND SILENCER
ÈExcept for USAExtent of removal:
1 Silencer removal
2 Exhaust pipe removal
Extent of removal Order Part name Q’ty Remarks
EXHAUST PIPE AND SILENCER
REMOVAL
Preparation for removal Right side cover Refer to “SEAT, FUEL TANK AND SIDE COVERS”
section.
1 Bolt (silencer clamp) 1 Only loosening.
2 Bolt [silencer (front)] 1
3 Bolt [silencer (rear)] 1
4 Silencer 1
5 Silencer clamp 1
6 Nut (exhaust pipe) 1
7 Bolt (exhaust pipe) 1
8 Exhaust pipe 1
9 Gasket 2
1
2
2

4 - 13
ENGRADIATOR
EC450001
RADIATOR
Extent of removal:
1 Radiator removal
Extent of removal Order Part name Q’ty Remarks
RADIATOR REMOVAL
Preparation for removal Drain the coolant. Refer to “COOLANT REPLACEMENT” section in the
CHAPTER 3.
Seat, fuel tank and left side cover Refer to “SEAT, FUEL TANK AND SIDE COVERS”
section.
1 Radiator guard 2
2 Radiator hose clamp 8 Only loosening.
3 Radiator hose 1 1
4 Left radiator 1
5 Radiator hose 3 1
6 Coolant reservoir hose 1
7 Right radiator 1
8 Radiator hose 2 1
9 Radiator hose 4 1
10 Radiator pipe 1
11 Coolant reservoir breather hose 1
12 Coolant reservoir 1
1

4 - 21
ENGCARBURETOR
CARBURETOR
97
8
1
T R..2 Nm (0.2 m •
kg, 1.4 ft • Ib)
T R..11 Nm (1.1 m •
kg, 8.0 ft • Ib)
T R..4 Nm (0.4 m •
kg, 2.9 ft • Ib)5 1
2
6
64
4
3
T R..3 Nm (0.3 m • kg, 2.2 ft • Ib)
T R..3 Nm (0.3 m • kg, 2.2 ft • Ib)
T R..4 Nm (0.4 m •
kg, 2.9 ft • Ib)
Extent of removal:
1 Carburetor removal
Extent of removal Order Part name Q’ty Remarks
CARBURETOR REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE COVERS”
section.
1 Clamp 2
2 Throttle position sensor lead coupler 1
3 Throttle cable cover 1
4 Throttle cable 2
5 Clamp (air filter joint) 1 Loosen the screw (air filter joint).
6 Clamp (carburetor joint) 2 Loosen the screws (carburetor joint).
7 Hot starter plunger 1
8 Carburetor assembly 1
9 Carburetor joint 1
1

4 - 33
ENGCARBURETOR
HANDLING NOTE
CAUTION:
Do not loosen the screws (throttle
position sensor) 1
except when
changing the throttle position sen-
sor due to failure because it will
cause a drop in engine perfor-
mance.
1
REMOVAL POINTS
Pilot screw
1. Remove:
Pilot screw
1
NOTE:To optimize the fuel flow at a small
throttle opening, each machine’s pilot
screw has been individually set at the
factory. Before removing the pilot
screw, turn it in fully and count the
number of turns. Record this number
as the factory-set number of turns
out.
INSPECTION
Carburetor
1. Inspect:
Carburetor body
Contamination
→ Clean.
NOTE:Use a petroleum based solvent for
cleaning. Blow out all passages
and jets with compressed air.
Never use a wire.
REMARQUE CONCERNANT LES
MANIPULATIONS
ATTENTION:
Ne pas desserrer les vis (capteur de
position du papillon des gaz) 1 sauf
lors du changement de capteur de
position du papillon des gaz en cas de
panne pour éviter les diminutions de
performance du moteur.
POINTS DE DEPOSE
Vis de richesse
1. Déposer:
Vis de richesse 1
N.B.:
Afin d’optimiser le flux de carburant à
petite ouverture des gaz, la vis de
richesse de chaque véhicule a été réglé
individuellement à l’usine. Avant de
remonter la vis de richesse, la visser
complètement en comptant le nombre de
tours exact. Retenir et noter ce chiffre et
dévisser la vis de ce nombre de tours.
CONTROLE
Carburateur
1. Contrôler:
Corps du carburateur
Encrassé → Nettoyer.
N.B.:
Pour le nettoyage, employer un dissol-
vant à base de pétrole. Passer tous les
conduits et gicleurs à l’air comprimé.
Ne jamais utiliser de fil.
CARBURATEUR

4 - 51
ENGCAMSHAFTS
CAMSHAFTS
CYLINDER HEAD COVER
Extent of removal:
1 Cylinder head cover removal
Extent of removal Order Part name Q’ty Remarks
CYLINDER HEAD COVER REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE COVERS”
section.
Carburetor Refer to “CARBURETOR” section.
1 Spark plug 1
2 Cylinder head breather hose 1
3 Oil tank breather hose 1
4 Bolt (cylinder head cover) 2
5 Cylinder head cover 1
6 Cylinder head cover gasket 1
7 Timing chain guide (top side) 1
1