Yamaha XG250, Service Manual

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CYLINDER HEAD
5-9
ment, replace the timing chain tensioner.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3. Check:
●
Cap bolt
●
Copper washer
●
Spring
●
One-way cam
●
Timing chain tensioner rod
Damage/wear
→
Replace the defective
part(s).
EAS24230
INSTALLING THE CYLINDER HEAD
1. Install:
●
Cylinder head gasket
●
Dowel pins
2. Install:
●
Cylinder head
●
Copper washers
●
Air induction system pipe
3. Tighten:
●
Cylinder head bolt
NOTE:
●
Lubricate the cylinder head bolts with engine
oil.
●
Tighten the cylinder head bolts in the proper
tightening sequence as shown and torque
them in two stages.
4. Install:
●
Camshaft sprocket
●
Dowel pin
●
Timing chain
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the Pickup coil rotor counterclockwise.
b. Align the “I” mark “a” on the Pickup coil rotor
with the stationary pointer “b” on the crank-
case cover.
c. Remove the wire from the timing chain.
d. Install the timing chain onto the camshaft
sprocket, and then install the camshaft
sprocket onto the camshaft.
NOTE:
●
When installing the camshaft sprocket, be
sure to keep the timing chain as tight as pos-
sible on the exhaust side.
●
Align the pin “e” on the camshaft with the slot
in the camshaft sprocket.
CAUTION:
ECA13740
Do not turn the crankshaft when installing
the camshaft(s) to avoid damage or improp-
er valve timing.
e. Align the “I” mark “c” on the camshaft sprock-
et with the stationary pointer “d” on the cylin-
der head.
Cylinder head bolt (226 mm)
22 Nm (2.2 m•kg, 16 ft•lb)
Cylinder head bolt (45 mm)
20 Nm (2.0 m•kg, 14 ft•lb)
1
New
New
T
R
.
.
1
2
3
4
5
6
a
b