Kohler Command PRO CH749, Руководство по обслуживанию

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9.4
Section 9
Inspection and Reconditioning
6 mm (0.24 in.)
Measure 6 mm above the
Bottom of Piston Skirt at
Right Angles to Piston Pin
Use the following procedure to accurately measure
the piston-to-bore clearance:
1. Use a micrometer and measure the diameter of
the piston 6 mm (0.24 in.) above the bo tt om of the
piston skirt and perpendicular to the piston pin.
See Figure 9-4.
Figure 9-4. Measuring Piston Diameter.
2. Use an inside micrometer, telescoping gauge, or
bore gauge and measure the cylinder bore. Take
the measurement approximately
63.5 mm
(2.5 in.) below the top of the bore and
perpendicular to the piston pin.
3. Piston-to-bore clearance is the di ff erence between
the bore diameter and the piston diameter (Step 2
minus Step 1).
Flywheel
Inspection
Inspect the fl ywheel for cracks and the fl ywheel
keyway for damage. Replace the fl ywheel if it is
cracked. Replace the fl ywheel, the cranksha ft , and
the key if fl ywheel key is sheared or the keyway is
damaged.
Inspect the ring gear for cracks or damage. Kohler
does not provide the ring gear as a serviceable part.
Replace the
fl ywheel if the ring gear is damaged.
Cylinder Head and Valves
Inspection and Service
A ft er cleaning, check the fl atness of the cylinder head
and the corresponding top surface of the crankcase,
using a surface plate or piece of glass and feeler gauge
as shown in Figure 9-5. The maximum allowable out
of
fl atness is 0.076 mm (0.003 in.) .
Figure 9-5. Checking Cylinder Head Flatness.
Carefully inspect the valve mechanism parts. Inspect
the valve springs and related hardware for excessive
wear or distortion. Check the valves and valve seat
area or inserts for evidence of deep pi
tt ing, cracks,
or distortion. Check clearance of the valve stems
in the guides. See Figure 9-6 for valve details and
speci
fi cations.