Kohler Command PRO ECH630 Service Manual page 123

Piston Ring
End Gap
Identifi cation
Mark
Oil Control Ring
(Three-piece)
Figure 9-12. Piston Ring Installation.
1. Oil Control Ring (Bott om 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 identifi cation
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 expender. Make sure
the identifi cation mark is up or the dykem stripe
(if contained), to the left of the end gap.
Dykem
Stripe
Piston
Top
Compression
Ring
Center
Compression
Ring
Rails
Expander
Inspection and Reconditioning
Connecting Rods
Off set, stepped-cap connecting rods are used in all
these engines.
Inspection and Service
Check the bearing area (big end) for excessive wear,
score marks, running and side clearances (refer to
Section 1, Specifi cations, 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.
The 0.25 mm (0.010 in.) undersized rod can be
identifi ed by the drilled hole located in the lower end
of the rod shank. Always refer to the appropriate parts
information to ensure that correct replacements are
used.
Hydraulic Lifters
Inspection
Check the base surface of the hydraulic lift ers for wear
or damage. If the lift ers need to be replaced, apply a
liberal coating of Kohler lubricant (see Section 2) to
the base of each new lift er 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
lift ers 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 lift er, open end up, on the
towel.
3. Lower the chucked push rod until it contacts the
plunger in the lift er. Slowly pump the plunger
two or three times to force the oil out of the feed
hole in the side of the lift er.
Section 9
9
9.11