Kohler Command PRO ECV630, Service Manual

Page: 120 / 152

9.10
Section 9
Inspection and Reconditioning
Figure 9-12. Piston Ring Installation.
1. Oil Control Ring (Bo tt om Groove): Install the
expander and then the rails. Make sure the ends
of the expander are not overlapped.
2. Middle Compression Ring (Center Groove):
Install the center ring using a piston ring
expander tool. Make sure the “identi
fi cation”
mark is up or the dykem stripe (if contained) is to
the le
ft of the end gap.
3. Top Compression Ring (Top Groove): Install the
top ring using a piston ring expander. Make sure
the “identi
fi cation” mark is up or the dykem
stripe (if contained), is to the le ft of the end gap.
Connecting Rods
O ff 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,
Speci fi 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 rods
have an identi fi cation marking on 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 li ft ers for wear
or damage. If the li ft ers need to be replaced, apply a
liberal coating of Kohler lubricant (see Section 2) to
the base of each new li
ft 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 li
ft 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 li ft er, open end up, on the
towel.
3. Lower the chucked push rod until it contacts the
plunger in the li ft er. Slowly “pump” the plunger
two or three times to force the oil out of the feed
hole in the side of the li
ft er.
Oil Pan Assembly
Inspection
Inspect the oil seal in the oil pan and remove it if it is
worn or damaged. Refer to
Install Oil Seal in Oil Pan
in Section 10 for new oil seal installation.
Inspect the main bearing surface for wear or damage
(refer to Section 1,
Speci fi cations, Tolerances, and
Special Torque Values ). Replace the oil pan assembly
if required.
Governor Gear Assembly
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.
Center
Compression
Ring
Piston Ring
End Gap
Identifi cation
Mark
Dykem
Stripe
Piston
Top
Compression
Ring
Rails
Expander
Oil Control Ring
(Three-piece)