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Disassembly/Inspection and Service
KohlerEngines.com
22 690 01 Rev. --
Some important points to remember when servicing
piston rings:
1. Cylinder bore must be deglazed before service ring
sets are used.
2. If cylinder bore is within wear limits (refer to
Specifi cations) and old piston is within wear limits,
free of score or scuff marks, old piston may be
reused.
3. Remove old rings and clean up grooves. Never
reuse old rings.
4. Before installing new rings on piston, place top 2
rings, each in turn, in its running area in cylinder
bore and check end gap. Top compression ring end
gap clearance is 0.150/0.400 mm (0.0059/0.0157
in.) for a new bore, or 0.770 mm (0.0300 in.) for a
used bore. Middle compression ring end cap is
1.000/1.250 mm (0.0394/0.0492 in.) for a new bore,
or 1.504 mm (0.0592 in.) for a used bore.
5. After installing new compression (top and middle)
rings on piston, make sure top compression ring-to-
groove side clearance and is 0.025/0.065 mm
(0.0010/0.0026 in.) and middle compression ring-to-
groove side clearance 0.040/0.080 mm
(0.0016/0.032 in.). If side clearance is greater than
specifi ed, a new piston must be used.
Piston and Rings
Piston and Rings Components and Details
C
E
A
B
D
F
A
Top Compression
Ring
B
Middle Compression
Ring
C
Oil Control Ring
D
Top Rail
E
Expander Ring
F
Rail
Install New Piston Rings
Piston Ring Orientation
E
A
D
B
C
A
Top Oil Rail Gap
B
Bottom Oil Rail Gap
C
Middle Ring Gap
D
Oil Ring Expander
Gap
E
Top Ring Gap
NOTE: Rings must be installed correctly. Use a piston
ring expander to install rings. Install bottom (oil
control) ring fi rst and top compression ring last.
To install piston rings, proceed as follows:
1. Oil control ring (bottom groove): Install expander and
then rails. Make sure ends of expander are not
overlapped.
2. Middle Compression ring (center groove): Install
center ring using a piston ring installation tool. Make
sure identifi cation mark is up when ring is installed.
3. Top Compression ring (top groove): Install top ring
using a piston ring installation tool. Make sure
identifi cation mark is up when ring is installed.
