Cylinder Head Cleaning and Inspection
Special Tools
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EN-6216-200/300/400
Gauge Instruments |
For equivalent regional tools refer to
Special Tools .
Cleaning Procedure
1. |
Remove any old thread sealant,
gasket material or sealant. |
2. |
Clean all cylinder head
surfaces with non-corrosive sealant. |
3. |
Blow out all the oil galleries
using compressed air. |
4. |
Remove any carbon deposits
from the combustion chamber. |
Visual Inspection
1. |
Inspect the cylinder head
camshaft bearing surfaces for the following conditions:
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• |
Excessive scoring or
pitting |
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• |
Discoloration from
overheating |
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Deformation from excessive
wear |
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• |
If the camshaft bearing
journals appear to be scored or damaged, you must replace the
cylinder head. DO NOT machine the camshaft bearing journals.
|
2. |
If any of the above conditions
exist on the camshaft bearing surfaces, replace the cylinder
head. |
3. |
Inspect the cylinder head for
the following: |
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• |
Cracks, damage or pitting in
the combustion chambers. |
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• |
Debris in the oil galleries -
Continue to clean the galleries until all debris is removed.
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• |
Coolant leaks or damage to the
deck face sealing surface - If coolant leaks are present, measure
the surface war page as described under cylinder head measurement -
deck flatness inspection. |
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• |
Damage to any gasket
surfaces. |
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• |
Burnt or eroded areas in the
combustion chamber. |
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• |
Cracks in the exhaust ports
and combustion chambers. |
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• |
External cracks in the water
passages. |
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• |
Restrictions in the intake or
exhaust passages. |
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• |
Restrictions in the cooling
system passages. |
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Rusted, damaged or leaking
core plugs. |
4. |
If the cylinder head is
cracked or damaged, it must be replaced. No welding or patching of
the cylinder head is allowed. |
Valve Inspection And Measurement
1. |
Clean the valves of carbon and
oil. Carbon can be removed with a wire brush. |
2. |
Inspect the valves for the
following conditions: |
|
2.1 |
Inspect the valve faces for
burning and cracking (1). If pieces are broken, replace the valve
and inspect the corresponding piston and cylinder head area for
damage. |
|
2.2 |
Inspect the valve for
straightness and distortion (2). Distorted valve must be
replaced. |
|
2.3 |
Inspect the valve stem for
wear (3). |
|
2.4 |
Inspect the valve key grooves
for chipping and wear (5). Replace the valve if chipped or
worn. |
4. |
Measure the valve stem
diameter. Use a micrometer gauge (2). Refer to
Engine Mechanical Specifications to find the permitted values.
Note the measurement results. |
Cylinder Head Measurement
1. |
Inspect the cylinder head
sealing surface for flatness. Use a straightedge (1). |
2. |
Prepare the gauge for valve
stem to guide clearance measurement. Assemble the EN-6216
gauge and the EN-6216-200/300/400 gauge
instruments as follows: |
|
2.1 |
Install the extension (5) to
the support (4). |
|
2.2 |
Install the inside caliper (2)
to the extension (5). |
|
2.3 |
Install the gauge (3) to the
support (4) and pretension to 1 mm (0.0394 in)
. |
|
2.4 |
Install the calibration washer
(1) as shown to justify the gauge. |
|
2.5 |
Adjust the gauge to 0
mm (0 in) by rotating the instrument dial. |
|
2.6 |
Cautious remove the
calibration washer (1). |
3. |
Measure the valve guide inner
diameter (2) as shown in different areas (3). Use EN-6216
gauge (1) and gauge instruments. Note the measurement
results. Refer to
Engine Mechanical Specifications to find the permitted
values. |
4. |
Substract the valve stem
diameter from valve guide inner diameter to calculate the valve
stem to guide clearance. Refer to
Engine Mechanical Specifications to find the permitted
values. |
5. |
Turn the cylinder head upside
down. |
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