F3B ENGINE 183 T RAKKER E URO 4/5 Selecting the main bearing and big end bearing shells NOTE To obtain the required assembly clearances, the main bearing and big end bearing shells have to be selected as described hereunder. This operation makes it possible to identify the most suited bearing shells for each of the journals of the shaft (the bearing shells may even have different classes for different pins). Depending on the thickness, the bearing shells are selected in classes oftolerance marked by a colour (red-green -red/black - green/black).
Figure 88 gives the specifications of the main bearing and big end bearing shells available as spare parts in the standard sizes (STD) and in the permissible oversizes (+0.127, +0.254, +0.508). Figure 88 STD +0.127 +0.254 +0.508 Big end bearing shells red 1.965 to 1.975 2.092 to 2.102 2.219 to 2.229 red/black 2.028 to 2.038 green 1.976 to 1.985 2.103 to 2.112 2.230 to 2.239 green/black 2.039 to 2.048 Main bearing shells STD +0.127 +0.254 +0.508 red 3.110 to 3.120 3.237 to 3.247 3.364 to 3.374 red/black 3.173 to 3.183 green 3.121 to 3.130 green/black 3.184 to 3.193 Print 603.93.641 Base q November2006