Kohler LH630-775 Service Manual page 139

Piston Ring
End Gap
"Identification
"Mark
Oil Control Ring
(Three-piece)
Expander
Figure 10-12. Piston Ring Installation.
1. Oil Control Ring (Bottom Groove): Install the
expander and then the rails. Make sure the ends
of expander are not overlapped.
2. Second Compression Ring (Center Groove):
Install the center ring using a piston ring
installation tool. Make sure the "pip" mark is up.
3. First Compression Ring (Top Groove): Install the
top ring using a piston ring installation tool. If no
"identification" mark exists to denote "up" the
ring is symmetrical and may be installed with
either side up.
Connecting Rods
Offset Stepped-Cap Connecting Rods are used in all
these engines.
Inspection and Service
Check bearing area (big end) for excessive wear,
score marks, running and side clearances (refer to
Section 1, ''Specifications, Tolerances, and Special
Torque Values''). Replace rod and cap if scored or
excessively worn.
Piston
Top Compression
Ring
Center Compression
Ring
Rails
Inspection and Reconditioning
Service replacement connecting rods are available in
STD crankpin size and 0.25 mm (0.010 in.) undersize.
The undersized rod is marked US 0.25 mm with
purple ink on the rod shank. Always refer to the
appropriate parts information to ensure that correct
replacements are used.
Closure Plate Assembly
Inspection
Inspect the oil seal in the closure plate and remove it if
it is worn or damaged. The new oil seal is installed
after the closure plate is assembled to the crankcase.
See ''Install Closure Plate Oil Seal'' in Section 11.
Inspect main bearing (if so equipped) for wear or
damage (refer to Section 1, ''Specifications, Tolerances,
and Special Torque Values''). Replace closure plate
assembly if required.
Governor Assembly (Internal)
Inspection
Inspect the governor gear teeth. Replace the gear if it
is worn, chipped, or if any teeth are missing.
Inspect the governor weights. They should move
freely in the governor gear.
Disassembly
The governor gear must be replaced once it is
removed from the closure plate.
NOTE: The governor gear is held onto the shaft by
small molded tabs in the gear. When the gear
is removed from the shaft, these tabs are
destroyed and the gear must be replaced.
Therefore, remove the gear only if absolutely
necessary.
1. Remove the regulating pin and governor gear
assembly. See Figure 10-13.
Section 10
10
10.11