Kohler ECV940 Service Manual page 140

Disassembly/Inspection and Service
Inspect crankpin for score marks or metallic pickup.
Slight score marks can be cleaned with crocus cloth
soaked in oil. If wear limits, as stated in Clearance
Specifi cations, are exceeded, it will be necessary to
replace crankshaft or regrind crankpin to 0.25 mm
(0.010 in.) undersize. If reground, a 0.25 mm (0.010 in.)
undersize connecting rod (big end) must then be used to
achieve proper running clearance. Measure crankpin for
size, taper, and out-of-round.
Clearance Specifi cations-Connecting Rod Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
Width
Connecting rod journal can be ground 1 size under.
When grinding a crankshaft, grinding stone deposits
can get caught in oil passages, which could cause
severe engine damage. Removing crankpin plug when
crankshaft is ground provides easy access for removing
any grinding deposits that may collect in oil passages.
Use following procedure to remove and replace plug.
Remove Crankshaft Plug
1. Drill a 3/16 in. hole through plug in crankshaft.
2. Thread a 3/4 in. or 1 in. long self-tapping screw with
a fl at washer into drilled hole. Flat washer must be
large enough to seat against shoulder of plug bore.
3. Tighten self-tapping screw until it draws plug out of
crankshaft.
Install New Crankshaft Plug
Use 1 single cylinder camshaft pin, as a driver and tap
plug into plug bore until it seats at bottom of bore. Make
sure plug is tapped in evenly to prevent leakage.
Remove Governor Gear Assembly (Mechanical
Governor Only)
Governor gear is held onto shaft by small molded tabs
in gear. When gear is removed from shaft, these tabs
are destroyed and gear must be replaced. Therefore,
remove gear only if absolutely necessary. If governor
cross shaft, yoke, or gear condition does not require
removal, governor gear may be left in place. If removal is
necessary, perform as follows:
1. Remove locking tab thrust washer and note
orientation.
2. Using a screwdriver, carefully pry upward to unseat
governor gear assembly from governor gear shaft.
Remove regulating pin and governor gear assembly.
3. Inspect governor gear shaft for wear or damage.
Remove shaft only if replacement is needed.
Inspection
Governor gear is located within crankcase. Inspect
governor gear teeth. Replace gear if it is worn, chipped,
or if any teeth are missing. Inspect governor weights.
They should move freely in governor gear.
140
43.982/44.000 mm
(1.731/1.732 in.)
43.97 mm (1.731 in.)
0.018 mm (0.0007 in.)
0.025 mm (0.0010 in.)
53.00/53.09 mm
(2.0866/2.0901 in.)
KohlerEngines.com
Remove Governor Yoke, Cross Shaft, and Seal
(Mechanical Governor Only)
1. Remove mounting screws securing yoke to governor
cross shaft.
2. Pull governor cross shaft out of crankcase and
remove seal.
Remove Lifter Feed Chamber Cover and Gaskets
Remove screws securing lifter feed chamber cover and
gaskets. Carefully separate parts from crankcase.
Remove Flywheel End Oil Seal
Remove oil seal from crankcase using a seal puller.
Crankcase
Inspection and Service
Check all gasket surfaces to make sure they are free of
gasket fragments. Gasket surfaces must also be free of
deep scratches or nicks.
Check cylinder bore for scoring. In severe cases,
unburned fuel can cause scuffi ng and scoring of cylinder
wall. It washes necessary lubricating oils off piston and
cylinder wall. As raw fuel seeps down cylinder wall,
piston rings make metal to metal contact with wall.
Scoring of cylinder wall can also be caused by localized
hot spots resulting from blocked cooling fi ns or from
inadequate or contaminated lubrication.
If cylinder bore is badly scored, excessively worn,
tapered, or out-of-round, resizing is necessary. Use an
inside micrometer to determine amount of wear, then
select nearest suitable oversize of either 0.25 mm (0.010
in.) or 0.50 mm (0.020 in.). Resizing to these oversizes
will allow usage of available oversize piston and ring
assemblies. Initially, resize using a boring bar, then use
following procedures for honing cylinder.
Honing
Detail
A 23°-33° Crosshatch
NOTE: Kohler pistons are custom-machined to exacting
tolerances. When oversizing a cylinder, it should
be machined exactly 0.25 mm (0.010 in.) or 0.50
mm (0.020 in.) over new diameter.
corresponding oversize Kohler replacement
piston will then fi t correctly.
A
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