Orion AGB-21G - Checking the Cylinder Head

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CYLINDER HEAD
NOTE:
NOTE:
NOTE:
6. Remove:
cylinder head
Loosen the
nuts ķĸĹĺĻ
in the proper sequence.
Loosen each nut 1/2 of a turn at a time.
After all of the nuts are fully loosened, remove
them.
CHECKING THE CYLINDER HEAD
1. Eliminate:
combustion chamber carbon deposits
(with a rounded scraper)
Do not use a sharp instrument to avoid damag-
ing or scratching:
spark plug threads
valve seats
2. Check:
cylinder head
Damage/scratches
Replace.
3. Measure:
cylinder head warpage
Out of specification
Resurface the cylin-
der head.
Cylinder head warpage
Less than 0.03 mm
a. Place a straightedge
1
and a thickness
gauge
2
across the cylinder head.
b. Measure the warpage.
c. If the limited is exceeded, resurface the cylin-
der head as follows.
d. Place a 400
600 grit wet abrasive paper
on the surface plate and resurface the cylin-
der head using a figure-eight sanding pat-
tern.
To ensure an even surface, rotate the cylinder
head several times.