1.12
Section 1
Safety and General Information
²Measure 6 mm (0.236 in.) above the bottom of the piston skirt at right angles to the piston pin.
Piston, Piston Rings, and Piston Pin
Piston-to-Piston Pin .............................................................................. 0.006/0.018 mm (0.0002/0.0007 in.)
Piston Pin Bore I.D.
New ................................................................................................ 17.006/17.013 mm (0.6695/0.6698 in.)
Max. Wear Limit ............................................................................. 17.025 mm (0.6703 in.)
Piston Pin O.D.
New ................................................................................................ 16.995/17.000 mm (0.6691/0.6693 in.)
Max. Wear Limit ............................................................................. 16.994 mm (0.6691 in.)
Top Compression Ring-to-Groove Side Clearance
LH630 ............................................................................................ 0.040/0.086 mm (0.0016/0.0034 in.)
LH685 ............................................................................................ 0.050/0.096 mm (0.0020/0.0038 in.)
LH750, LH760 ................................................................................ 0.014/0.041 mm (0.0005/0.0016 in.)
Middle Compression Ring-to-Groove Side Clearance
LH630 ............................................................................................ 0.040/0.086 mm (0.0016/0.0034 in.)
LH685 ............................................................................................ 0.030/0.076 mm (0.0012/0.0030 in.)
LH750, LH760 ................................................................................ 0.012/0.039 mm (0.0004/0.0015 in.)
Oil Control Ring-to-Groove Side Clearance
LH630 ............................................................................................ 0.046/0.196 mm (0.0018/0.0077 in.)
LH685 ............................................................................................ 0.046/0.196 mm (0.0018/0.0077 in.)
LH750, LH760 ................................................................................ 0.026/0.176 mm (0.0010/0.0070 in.)
Top and Middle Compression Ring End Gap
LH630
New Bore
Top Ring ............................................................................ 0.180/0.380 mm (0.0071/0.0150 in.)
Middle Ring ....................................................................... 0.250/0.450 mm (0.0098/0.0177 in.)
Used Bore (Max.) .................................................................... 0.77 mm (0.030 in.)
LH685
New Bore
Top Ring ............................................................................ 0.180/0.430 mm (0.0071/0.0169 in.)
Middle Ring ....................................................................... 0.250/0.460 mm (0.0098/0.0181 in.)
Used Bore (Max.) .................................................................... 0.80 mm (0.0315 in.)
LH750, LH760
New Bore ................................................................................. 0.250/0.56 mm (0.0098/0.022 in.)
Used Bore ............................................................................... 0.94 mm (0.037 in.)
Piston Thrust Face O.D.²
LH630
New ......................................................................................... 76.967/76.985 mm (3.0302/3.0309 in.)
Max. Wear Limit ...................................................................... 76.840 mm (3.0252 in.)
LH685
New ......................................................................................... 79.963/79.981 mm (3.1481/3.1488 in.)
Max. Wear Limit ...................................................................... 79.831 mm (3.1430 in.)
LH750, LH760
New ......................................................................................... 82.973/82.991 mm (3.2666/3.2673 in.)
Max. Wear Limit ...................................................................... 82.841 mm (3.3136 in.)
Not For Resale
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