Section 9
Inspection and Reconditioning
9
9.11
Figure 9-12. 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. Middle Compression Ring (Center Groove):
Install the center ring using a piston ring
installation tool. Make sure the identification
mark is up or the dykem stripe (if contained), is
to the left of the end gap.
3. Top Compression Ring (Top Groove): Install the
top ring using a piston ring expander. Make sure
the identification mark is up or the dykem stripe
(if contained), is to the left of the end gap.
Connecting Rods
Offset, stepped-cap connecting rods are used in these
engines.
Inspection and Service
Check the bearing area (big end) for excessive wear,
score marks, running and side clearances (refer to
Section 1, Specifications, Tolerances, and Special
Torque Values). Replace the rod and cap if scored or
excessively worn.
Service replacement connecting rods are available in
STD crankpin size and
0.25 mm (0.010 in.)
undersize.
Always refer to the appropriate parts information to
ensure that correct replacements are used.
Hydraulic Lifters
Inspection
Check the base surface of the hydraulic lifters for
wear or damage. If the lifters need to be replaced,
apply a liberal coating of Kohler lubricant (see
Section 2) to the base of each new lifter before it is
installed.
“Bleeding” the Lifters
To prevent a possible bent push rod or broken rocker
arm, it is important to “bleed” any excess oil out of
the lifters before they are installed.
1. Cut a 50-75 mm (2-3 in.) piece from the end of an
old push rod and chuck it in a drill press.
2. Lay a rag or shop towel on the table of the drill
press and place the lifter, open end up, on the
towel.
3. Lower the chucked push rod until it contacts the
plunger in the lifter. Slowly “pump” the plunger
two or three times to force the oil out of the feed
hole in the side of the lifter.
Governor Gear Assembly
Inspection
The governor gear is located within the crankcase.
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 crankcase.
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.
Piston Ring
Piston
Top Compression
Ring
Center Compression
Ring
Rails
Expander
Oil Control Ring
(Three Piece)
End Gap
Identification
Mark
