Removing The Cylinder Head; Checking The Cylinder Head; Installing The Cylinder Head - Yamaha 2011 FZ8NA(C) Service Manual

EAS24120

REMOVING THE CYLINDER HEAD

1. Remove:
• Intake camshaft
• Exhaust camshaft
Refer to "REMOVING THE CAM-
SHAFTS" on page 5-13.
2. Remove:
• Cylinder head nuts
• Cylinder head bolts
TIP
• Loosen the nuts in the proper sequence as
shown.
• Loosen each nut 1/2 of a turn at a time. After
all of the nuts are fully loosened, remove
them.
EAS24160

CHECKING THE CYLINDER HEAD

1. Eliminate:
• Combustion chamber carbon deposits
(with a rounded scraper)
TIP
Do not use a sharp instrument to avoid damag-
ing or scratching:
• Spark plug bore threads
• Valve seats
2. Check:
• Cylinder head
Damage/scratches → Replace.
• Cylinder head water jacket
Mineral deposits/rust → Eliminate.
3. Measure:
• Cylinder head warpage
Out of specification → Resurface the cyl-
inder head.
Warpage limit
0.10 mm (0.0039 in)
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a. Place a straightedge "1" and a thickness
gauge "2" across the cylinder head.
Thickness gauge
90890-03180
Feeler gauge set
YU-26900-9
b. Measure the warpage.
c. If the limit is exceeded, resurface the cylin-
der head as follows.
d. Place a 400–600 grit wet sandpaper on the
surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
TIP
To ensure an even surface, rotate the cylinder
head several times.
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EAS24240

INSTALLING THE CYLINDER HEAD

1. Check:
• Cylinder stud bolts "1"
Cylinder stud bolt
8 Nm (0.8 m·kgf, 5.8 ft·lbf)
TIP
Retighten the cylinder stud bolts to specifica-
tion, before installing the cylinder head.
5-21
CYLINDER HEAD