Kohler CH18 User Manual

Specifi cations
12 24 690 06 Rev. PKohlerEngines.com
CLEARANCE SPECIFICATIONS
4
CH18/CH20/
CH22/
CH620/CH621/
CH640/CH641
CH22/CH23/
CH620
8
/
CH640
8
/
CH670/CH680
CH25/
CH730/
CH740 CH750
Piston, Piston Rings, and Piston Pin (Style A continued)
Middle Compression Ring-to-Groove Side Clearance 0.040/
0.080 mm
(0.0016/
0.0031 in.)
0.030/
0.076 mm
(0.0012/
0.0030 in.)
0.015/0.037 mm
(0.0006/0.0015 in.)
Oil Control Ring-to-Groove Side Clearance 0.060/
0.202 mm
(0.0024/
0.0080 in.)
0.046/
0.196 mm
(0.0018/
0.0077 in.)
0.026/0.176 mm
(0.0010/0.0070 in.)
Top and Middle Compression Ring End Gap
New Bore
0.25/
0.45 mm
(0.0098/
0.0177 in.)
0.18/
0.46 mm
(0.0071/
0.0181 in.)
0.25/0.56 mm
(0.0100/0.0224 in.)
Used Bore (Max) 0.77 mm
(0.030 in.)
0.80 mm
(0.0315 in.)
0.94 mm (0.037 in.)
Thrust Face O.D.
9
New 76.943/
76.961 mm
(3.0292/
3.0299 in.)
79.943/
79.961 mm
(3.1473/
3.1480 in.)
82.949/82.967 mm
(3.2656/3.2664 in.)
Max. Wear Limit 76.816 mm
(3.0242 in.)
79.816 mm
(3.1423 in.)
82.822 mm (3.2606 in.)
Piston Thrust Face-to-Cylinder Bore
9
Running
Clearance
New 0.039/0.082 mm (0.0015/0.0032 in.)
Piston Style B
Piston-to-Piston Pin Running Clearance 0.006/0.017 mm (0.0002/0.0007 in.)
Pin Bore I.D.
New
Max. Wear Limit
17.006/17.012 mm (0.6695/0.6698 in.)
17.025 mm (0.6703 in.)
Pin O.D.
New
Max. Wear Limit
16.995/17.000 mm (0.6691/0.6693 in.)
16.994 mm (0.6691 in.)
Top Compression Ring-to-Groove Side Clearance 0.030/0.070 mm (0.001/0.0026 in.)
Middle Compression Ring-to-Groove Side Clearance 0.030/0.070 mm (0.001/0.0026 in.)
Oil Control Ring-to-Groove Side Clearance 0.060/0.190 mm (0.0022/0.0073 in.)
Top Compression Ring End Gap
New Bore 0.100/
0.279 mm
(0.0039/
0.0110 in.)
0.189/0.277 mm
(0.0074/0.0109 in.)
Used Bore (Max) 0.490 mm
(0.0192 in.)
0.531 mm (0.0209 in.)
4
Values are in Metric units. Values in parentheses are English equivalents.
8
CH620/CH640 engines changed from 624cc to 674cc; displacement can be confi rmed on engine nameplate.
9
Measure 6 mm (0.2362 in.) above bottom of piston skirt at right angles to piston pin.

Kohler CH18 Specifications

General

Brand	Kohler
Model	CH18
Category	Engine
Language	English