Installing The Cylinder Head - Yamaha YZ450F Owner's Service Manual

INSTALLING THE CYLINDER HEAD

EAS1SL5219
1. Install:
• Timing chain guide (intake side) "1"
• Dowel pin "2"
• Cylinder head gasket "3"
• Cylinder head "4"
TIP
While pulling up the timing chain, install the tim-
ing chain guide (intake side) and the cylinder
head.
3
1
2. Install:
• Washer "1"
• Bolt "2"
• Bolt "3"
2
TIP
Tighten the bolts using the following procedure.
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a. Wash the threads and contact surfaces of
the bolts, the contact surfaces of the wash-
ers, the contact surface of the cylinder head,
and the threads of the crankcase.
b. Apply molybdenum disulfide grease to the
threads and contact surfaces of the bolts
and to both contact surfaces of the washers
"1".
c. Install the washers and the bolts.
d. Tighten the bolts to the specified torque in
two or three steps in the proper tightening
sequence as shown.
New
4
2
2
2
1
3
Bolts "1"–"4"
1st
30 Nm (3.0 m·kgf, 22 ft·lbf)
x2 x4
1
5
6
4
e. Remove the bolts.
f. Again apply molybdenum disulfide grease to
the threads and contact surfaces of the bolts
and to both contact surfaces of the washers.
g. Retighten the bolts.
TIP
Tighten the bolts to the specified torque in two
or three steps in the proper tightening se-
quence as shown.
Bolts "1"–"4"
2nd
20 Nm (2.0 m·kgf, 14 ft·lbf)
h. Put a mark on the corner "1" of the bolt (cyl-
inder head) and the cylinder head "2" as
shown.
5-22
CYLINDER HEAD
FWD
3
2
1
2