Service Manual

9
Specifi cations
66 690 01 Rev. C KohlerEngines.com
CLEARANCE SPECIFICATIONS
3
LH630 LH640 LH685 LH690 LH750 LH755
Governor
Governor Cross Shaft to Crankcase Running
Clearance
0.025/0.126 mm (0.0009/0.0049 in.)
Governor Cross Shaft O.D.
New
Max. Wear Limit
7.949/8.000 mm (0.3129/0.3149 in.)
7.936 mm (0.3124 in.)
Governor Gear Shaft O.D.
New
Max. Wear Limit
5.990/6.000 mm (0.2358/0.2362 in.)
5.977 mm (0.2353 in.)
Governor Gear Shaft -to-Governor Gear Running
Clearance
0.090/0.160 mm (0.0035/0.0063 in.)
Ignition
Spark Plug Gap 0.76 mm (0.030 in.)
Ignition Module Air Gap 0.203/0.305 mm (0.008/0.012 in.)
Piston, Piston Rings, and Piston Pin
Piston Style A
Piston-to-Piston Pin 0.006/0.018 mm (0.0002/0.0007 in.)
Piston Pin Bore I.D.
New
Max. Wear Limit
17.006/17.013 mm (0.6695/0.6698 in.)
17.025 mm (0.6703 in.)
Piston 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 0.040/0.086 mm
(0.0016/0.0034 in.)
0.050/0.096 mm
(0.0020/0.0038 in.)
0.014/0.041 mm
(0.0005/0.0016 in.)
Middle Compression Ring-to-Groove Side Clearance 0.040/0.086 mm
(0.0016/0.0034 in.)
0.030/0.076 mm
(0.0012/0.0030 in.)
0.012/0.039 mm
(0.0004/0.0015 in.)
Oil Control Ring-to-Groove Side Clearance 0.046/0.196 mm
(0.0018/0.0077 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
Top Ring 0.180/0.380 mm
(0.0071/0.0150 in.)
0.180/0.430 mm
(0.0071/0.0169 in.)
0.250/0.56 mm
(0.0098/0.022 in.)
Middle Ring 0.250/0.450 mm
(0.0098/0.0177 in.)
0.250/0.460 mm
(0.0098/0.0181 in.)
----
Used Bore (Max.) 0.77 mm
(0.030 in.)
0.80 mm
(0.0315 in.)
0.94 mm
(0.037 in.)
Piston Thrust Face O.D.
7
New 76.968/76.986 mm
(3.0302/3.0309 in.)
79.963/79.981 mm
(3.1481/3.1488 in.)
82.973/82.991 mm
(3.2666/3.2673 in.)
Max. Wear Limit 76.840 mm
(3.0252 in.)
79.831 mm
(3.1430 in.)
82.841 mm
(3.3136 in.)
Piston Thrust Face-to-Cylinder Bore
7
Running
Clearance
0.014/0.057 mm
(0.0005/0.0022 in.)
0.019/0.062 mm
(0.0007/0.0024 in.)
0.015/0.058 mm
(0.005/0.0022 in.)
3
Values are in Metric units. Values in parentheses are English equivalents.
7
Measure 6 mm (0.2362 in.) above bottom of piston skirt at right angles to piston pin.