Remove Camshaft; Remove Connecting Rods With Pistons And Rings; Connecting Rods; Piston And Rings - Kohler CH940-CH1000 Service Manual

Disassembly
Reassembly
1. Make sure recess in closure plate for oil pump
gerotor gears is clean.
2. Lubricate oil pump gerotor gears with grease
(Lubriplate ® 100 or equivalent), and install into
recess.
3. Lightly lubricate with oil and install inlet seal into oil
pump housing until it is fully seated.
4. Install O-ring in groove of oil pump housing. Use a
small quantity of grease to hold it in place.
5. Lightly lubricate I.D. of inlet seal with oil and carefully
insert ferruled end of pickup tube through grommet,
into oil pump housing. Position pickup tube so
outboard end faces up.
6. Install oil pump housing with pickup tube, over oil
pump boss and gears. Position relief valve baffl e on
screws 2 and 3. Align three screw hole locations.
7. Install clamp for pickup tube and fi nger tighten
screw. Check alignment of parts and torque oil pump
housing screws as specifi ed using sequence below:
a. Install fastener into location No. 1 and lightly
tighten to position pump.
b. Install fastener into location No. 2 and fully torque
to recommended value.
c. Install fastener into location No. 3 and fully torque
to recommended value.
d. Finish torquing fastener in location No. 1 to
recommended value.
Tighten hex fl ange screws to torque specifi cations.
8. Torque clamp (pickup tube) mounting screw to
torque specifi cations.

Remove Camshaft

Remove camshaft and shim (if used).
Inspection and Service
Check lobes of camshaft for wear or damage. Inspect
cam gear for badly worn, chipped, or missing teeth.
Replacement of camshaft will be necessary if any of
these conditions exist.

Remove Connecting Rods with Pistons and Rings

NOTE: If a carbon ridge is present at top of either
cylinder bore, use a ridge reamer tool to remove
ridge before attempting to remove piston.
NOTE: Cylinders are numbered on crankcase. Use
numbers to mark each end cap, connecting rod
and piston for reassembly. Do not mix end caps
and connecting rods.
1. Remove two hex fl ange screws securing closest
connecting rod end cap. Remove end cap.
2. Carefully remove connecting rod and piston
assembly from cylinder bore.
3. Repeat above procedures for or connecting rod and
piston assembly.

Connecting Rods

Offset, stepped-cap connecting rods are used in these
engines.
52
Inspection and Service
Check bearing area (big end) for excessive wear, score
marks, running and side clearances. Replace 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 appropriate parts information to ensure
that correct replacements are used.

Piston and Rings

Piston Ring
A
Identifi cation
C
Top Compression
E
G
Oil Control Ring
I
(Three Piece)
Inspection
Scuffi ng and scoring of pistons and cylinder walls occurs
when internal engine temperatures approach welding
point of piston. Temperatures high enough to do this are
created by friction, which is usually attributed to improper
lubrication and/or overheating of engine.
Normally, very little wear takes place in piston boss-
piston pin area. If original piston and connecting rod can
be reused after new rings are installed, original pin can
also be reused but new piston pin retainers are required.
Piston pin is included as part of piston assembly – if pin
boss in piston or pin are worn or damaged, a new piston
assembly is required.
KohlerEngines.com
A
B
C
I
B
D
Mark
F
Ring
Rails
H
D
E
F
G
H
End Gap
Piston
Center
Compression
Ring
Expander
62 690 01 Rev. C