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ENG
CYLINDER HEAD
CHECKING THE CYLINDER HEAD
1.Eliminate:
●Carbon deposits (from the combustion
chambers)
Use a rounded scraper.
N
OTE:
Do not use a sharp instrument to avoid
damaging or scratching:
●Spark plug threads
●Valve seats
2.Check:
●Cylinder head
Scratches/damage → Replace.
●Cylinder head water jacket
Mineral deposits/rust → Eliminate.
3.Measure:
●Cylinder head warpage
Out of specification → Resurface.
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Measurement and resurfacing steps:
●Place a straightedge and a feeler gauge
across the cylinder head.
●Use a feeler gauge to measure the warpage.
●If the warpage is out of specification,
resurface the cylinder head.
●Place a 400 ~ 600 grit wet sandpaper on the
surface plate, and resurface the head using
a figure-eight sanding pattern.
N
OTE:
To ensure an even surface rotate the cylinder
head several times.
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Cylinder head warpage:
Less than 0.03 mm (0.012 in)