Cam Gears; Crankshaft And Crank Gear; Crankcase - Kohler Courage SV470 Service Manual

Section 9
Inspection and Reconditioning
Reducing the compression at cranking speeds results
practical for the applications in which these
engines are used.
2. ACR eliminates kickback during starting, so a
spark retard/advance mechanism is no longer
required.
the opened exhaust valve and does not hamper
starting.
4. Engines with ACR start much faster in cold
weather.
5. Engines with ACR can be started with spark
plugs that are worn or fouled. Engines without
ACR would be less likely to start with the same
plugs.

Cam Gears

Inspection and Service
Inspect the gear teeth and cam lobes of the intake and
exhaust cam gears. If the lobes exhibit excessive wear,
or the teeth are worn, chipped or broken, replacement
of the cam gear(s) will be necessary.

Crankshaft and Crank Gear

Inspection and Service
Inspect the teeth of the crank gear. If the teeth
are badly worn, chipped, or some are missing,
replacement of the crank gear will be necessary.
wear, scoring, grooving, etc. If they show signs of
9.2
Inspect the crankpin for wear, score marks or
aluminum transfer. Slight score marks can be cleaned
with crocus cloth soaked in oil. If wear limits are
exceeded (see Section 1), it will be necessary to replace

Crankcase

Inspection and Service
Check all gasket surfaces to make sure they are free of
gasket fragments and deep scratches or nicks.
Check the cylinder wall for scoring. In severe cases,
unburned fuel can wash the necessary lubricating
make metal to metal contact with the wall, causing
also be caused by localized hot spots from blocked
lubrication.
If the cylinder bore is scored, worn, tapered, or out-
of-round, resizing may be possible. Use an inside
micrometer or telescoping gauge to determine the
amount of wear (refer to Section 1). If wear exceeds
the published limits, a 0.08 mm (0.003 in.) oversize
piston is available. If the cylinder will not clean
up at 0.08 mm (0.003 in.) oversize, a short block or
replacement engine will need to be considered.
Honing
While most commercially available cylinder hones
can be used with either portable drills or drill presses,
the use of a low speed drill press is preferred as it
facilitates more accurate alignment of the bore in
accomplished at a drill speed of about 250 RPM and
60 strokes
hone, proceed as follows:
adjust it so that the stones are in contact with
cooling agent is recommended.
2. With the lower edge of each stone positioned
even with the lowest edge of the bore, start the
drill and honing process. Move the hone up and
down while resizing to prevent the formation of
sure the bore is cool when measuring.