Kohler Command PRO ECV630 Service Manual page 100

Disassembly/Inspection and Service
Remove Camshaft
Remove camshaft.
Inspection and Service
Check lobes of camshaft for wear or damage. See
Specifications for minimum lift tolerances. Measurement
must be performed while valve train is still assembled.
Inspect cam gear for badly worn, chipped or missing
teeth. Replacement of camshaft will be necessary if any
of these conditions exist.
Remove Governor Cross Shaft
1. Remove retainer and nylon washer, from governor
cross shaft.
2. Remove cross shaft through inside of crankcase.
Governor Cross Shaft Oil Seal
Cross Shaft Oil Seal Details
A
A 2.0 mm (0.0787 in.)
B Governor Cross Shaft Seal
If governor cross shaft seal is damaged and/or leaks,
replace it using these following procedures.
Remove oil seal from crankcase and replace it with a
new one. Install new seal to depth shown using a seal
installer.
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
it 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 screws securing closest connecting rod end
cap. Remove end cap.
2. Carefully remove connecting rod and piston
assembly from cylinder bore.
3. Repeat above procedure for other connecting rod
and piston assembly.
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B
KohlerEngines.com
4. Remove piston pin from piston for inspection. Use a
small screwdriver to pry pin retainer out of groove.
Inspection
Piston and Rings Components and Details
A
I
A Piston Ring
C Identification Mark
Top Compression
E
Ring
G Rails
Oil Control Ring
I
(3 Piece)
Scuffing 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.
B
J
C
D
E
F
G
H
B End Gap
D Piston
Center Compression
F
Ring
H Expander
J Dye Colored Stripe
24 690 02 Rev. D