Removing The Cylinder Head; Checking The Cylinder Head; Installing The Cylinder Head - Yamaha FZ1-N Service Manual

EAS24120

REMOVING THE CYLINDER HEAD

1. Remove:
• Intake camshaft
• Exhaust camshaft
Refer to "REMOVING THE CAMSHAFTS"
on page 5-12.
2. Remove:
• Cylinder head nuts
• Cylinder head bolts
NOTE:
• 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)
NOTE:
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 cylin-
der head.
Maximum cylinder head
warpage
0.10 mm (0.0039 in)
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a. Place a straightedge "1" and a thickness
gauge "2" across the cylinder head.
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.
NOTE:
To ensure an even surface, rotate the cylinder
head several times.
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EAS24240

INSTALLING THE CYLINDER HEAD

1. Check:
• Cylinder head bolts "1"
Cylinder head bolt
8 Nm (0.8 m·kg, 5.8 ft·lb)
NOTE:
Retighten the cylinder head bolts to specifica-
tion, before installing the cylinder head.
2. Install:
5-20
CYLINDER HEAD