Specifi cations CLEARANCE SPECIFICATIONS 3 LH630 LH640 LH685 LH690 LH750 LH755 Governor Ignition Piston, Piston Rings, and Piston Pin 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. 66 690 01 Rev. C KohlerEngines.com 9 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.) Spark Plug Gap 0.76 mm (0.030 in.) Ignition Module Air Gap 0.203/0.305 mm (0.008/0.012 in.) 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 Middle Ring 0.180/0.380 mm (0.0071/0.0150 in.) 0.250/0.450 mm (0.0098/0.0177 in.) 0.180/0.430 mm (0.0071/0.0169 in.) 0.250/0.460 mm (0.0098/0.0181 in.) 0.250/0.56 mm (0.0098/0.022 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 Bore7 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.)