60 F2B ENGINE T RAKKER E URO 4/5 Selecting the main and big end bearing shells NOTE To obtain the required assembly clearances, the main and big end bearing shells need to be selected as described hereunder. This operation makes it possible to identify the most suitable bearing shells for each ofthe journals (the bearing shells, if necessary, can have different classes from one journal to another). Depending on the thickness, the bearing shells are selected in classes of tolerance marked by a coloured sign (red-green q red/black q green/black).
The following tables give the specifications of the main and big end bearing shells available as spares in the standard sizes (STD) and in the permissible oversizes (+0.127, +0.254, +0.508).
Figure 73 STD +0.127 +0.254 +0.508 red 2.000 to 2.010 2.127 to 2.137 2.254 to 2.264 red/black 2.063 to 2.073 green 2.011 to 2.020 2.138 to 2.147 2.265 to 2.274 green/black 2.074 to 2.083 yellow* 2.021 to 2.030 yellow/black* 2.084 to 2.093 STD +0.127 +0.254 +0.508 red 3.000 to 3.010 3.127 to 3.137 2.254 to 3.264 red/black 3.063 to 3.073 green 3.011 to 3.020 green/black 3.074 to 3.083 yellow* 3.021 to 3.030 yellow/black* * Fitted in production only and not supplied as spares 3.084 to 3.093 Base q November 2006 Print 603.93.641