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5-20
CYLINDER HEAD
ENG
NOTE:
NOTE:
NOTE:
EAS00223
REMOVING THE CYLINDER HEAD
1. Remove:
S
cylinder head bolts
S
cylinder head nuts
S
Loosen the nuts in the proper sequence as
shown.
S
Loosen each nut 1 / 2 of a turn at a time. After all
of the nuts are fully loosened, remove them.
EAS00229
CHECKING THE CYLINDER HEAD
1. Eliminate:
S
combustion chamber carbon deposits
(with a rounded scraper)
Do not use a sharp instrument to avoid damag-
ing or scratching:
S
spark plug bore threads
S
valve seats
2. Check:
S
cylinder head
Damage / scratches
!
Replace.
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cylinder head water jacket
Mineral deposits / rust
!
Eliminate.
3. Measure:
S
cylinder head warpage
Out of specification
!
Resurface the cylin-
der head.
Maximum cylinder head warpage
Less than 0.10 mm
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 cylinder
head as follows.
d. Place a 400
X
600 grit wet sandpaper on the
surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
To ensure an even surface, rotate the cylinder
head several times.