Kohler LH630-775 Service Manual page 132

Section 10
Inspection and Reconditioning
Measure 6 mm Above the
Bottom of Piston Skirt at
Right Angles to Piston Pin.
Figure 10-4. 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 difference
between the bore diameter and the piston
diameter (step 2 minus step 1).
Flywheel
Inspection
Inspect the flywheel for cracks, and the flywheel
keyway for damage. Replace flywheel if cracked.
Replace the flywheel, the crankshaft, and the key if
flywheel key is sheared or the keyway is damaged.
Inspect the ring gear for cracks or damage. Kohler
does not provide ring gears as a serviceable part.
Replace the flywheel if the ring gear is damaged.
Check the charging system magnets to be sure they
are not loose or cracked.
Cylinder Head and Valves
Inspection and Service
After cleaning, check the flatness 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 10-5. The maximum allowable out
of flatness is 0.076 mm (0.003 in.).
10.4
6 mm
(0.24 in.)
Figure 10-5. 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 pitting, cracks, or
distortion. Check clearance of the valve stems in
guides. See Figure 10-6 for valve details and
specifications.