Kohler CH680 Service Manual

Specifi cations
10 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
Connecting Rod
Connecting Rod-to-Crankpin Running Clearance
New
Max. Wear Limit
0.030/0.055 mm (0.0012/0.0022 in.)
0.070 mm (0.0028 in.)
Connecting Rod-to-Crankpin Side Clearance 0.26/0.63 mm (0.0102/0.0248 in.)
Connecting Rod-to-Piston Pin Running Clearance 0.015/0.028 mm (0.0006/0.0011 in.)
Piston Pin End I.D.
New
Max. Wear Limit
17.015/17.023 mm (0.6699/0.6702 in.)
17.036 mm (0.6707 in.)
Crankcase
Governor Cross Shaft Bore I.D.
6 mm Shaft
New
Max. Wear Limit
8 mm Shaft
New
Max. Wear Limit
6.025/6.050 mm (0.2372/0.2382 in.)
6.063 mm (0.2387 in.)
8.025/8.075 mm (0.3159/0.3179 in.)
8.088 mm (0.3184 in.)
Crankshaft
End Play (free) 0.070/0.590 mm (0.0028/0.0230 in.)
End Play (w/thrust bearing components) 0.070/1.190 mm (0.0028/0.0468 in.)
Except CH25 Engines Below Serial No. 2403500008 0.050/0.750 mm (0.0020/0.0295 in.)
Bore (in crankcase)
New
Max. Wear Limit
40.965/41.003 mm (1.6128/1.6143 in.)
41.016 mm (1.6148 in.)
Crankshaft to Sleeve Bearing (crankcase)
Running Clearance-New 0.03/0.09 mm (0.0012/0.0035 in.)
Bore (in closure plate)
New 40.987/40.974 mm (1.6136/1.6131 in.)
Crankshaft Bore (in closure plate)-to-Crankshaft
Running Clearance-New 0.039/0.074 mm (0.0015/0.0029 in.)
Flywheel End Main Bearing Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
40.913/40.935 mm (1.6107/1.6116 in.)
40.84 mm (1.608 in.)
0.022 mm (0.0009 in.)
0.025 mm (0.0010 in.)
Closure Plate End Main Bearing Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
40.913/40.935 mm (1.6107/1.6116 in.)
40.84 mm (1.608 in.)
0.022 mm (0.0009 in.)
0.025 mm (0.0010 in.)
Connecting Rod Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
35.955/35.973 mm (1.4156/1.4163 in.)
35.94 mm (1.415 in.)
0.018 mm (0.0007 in.)
0.025 mm (0.0010 in.)
T.I.R.
PTO End, Crank in Engine
Entire Crank, in V-Blocks
0.279 mm (0.0110 in.)
0.10 mm (0.0039 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.

Kohler CH680 Specifications

General

Displacement	674 cc
Compression Ratio	8.5:1
Fuel System	Carburetor
Ignition System	Electronic
Cooling System	Air-cooled
Starter	Electric
Engine Type	4-cycle, overhead valve (OHV)
Oil Capacity	1.9 L (2.0 U.S. qt)
Lubrication	Full Pressure
Power	22 hp (16.4 kW) at 3600 rpm