Kohler Command PRO CS, Service Manual

Page: 117 / 162

10.5
Section 10
Internal Components
10
Closure Plate and Crankcase
1. Clean the sealing surfaces of the closure plate and
crankcase of all gasket material.
NOTE: Do not scrape the surfaces when cleaning as
this will damage the surfaces and could cause
leaks. The use of a gasket-removing solvent
or aerosol spray is recommended.
Figure 10-9. Measuring Piston Diameter.
Use the following procedure to accurately measure
the piston-to-bore clearance:
1. Use a micrometer and measure the diameter of
the piston at location indicated above the bottom
of the piston skirt and perpendicular to the piston
pin. See Figure 10-9.
2. Use an inside micrometer, telescoping gauge, or
bore gauge and measure the cylinder bore. Take
the measurement approximately
40 mm (1.6 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 damaged.
Inspect the ring gear for wear, cracks, or damage.
Kohler does not provide ring gears as a serviceable
part. Replace the flywheel if the ring gear is damaged.
Figure 10-8. Removing Gasket with Aerosol Spray.
Measuring Piston-to-Bore Clearance
Before installing the piston into the cylinder bore, it is
necessary that the clearance be accurately checked.
This step is often overlooked, and if the clearances are
not within specifications, engine failure will usually
result.
NOTE: Do not use a feeler gauge to measure
piston-to-bore clearance – it will yield
inaccurate measurements. Always use a
micrometer.
For CS4, CS6: x = 5 mm (0.197 in.)
For CS8.5-12: x = 10 mm (0.394 in.)
x