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Crankshaft dimensions > < Allocation of main bearing shells for new crankshafts

A4 Cabriolet Mk2

Allocation of main bearing shells on used and machined crankshafts
Allocation of main bearing shells on used and machined crankshafts
   
Matching crankshaft bearing shells to bearings in cylinder block
t  Bearing shells are allocated to the cylinder block according to the colour codes stamped on the cylinder block.
t  On used and machined crankshafts, the main bearing journals must be measured in order to select the correct bearing shells.
t  Basic dimension for main bearing journal = Ø 65 mm
t  Repair undersize for main bearing journal = Ø 64.75 mm
t  There are thicker bearing shells available for machined crankshafts. However, these bearing shells have the same coloured marking as the original size bearing shells.
  A13-10153
Letter on cylinder blockColour coding of bearing
R=Red
G=Yellow
B=Blue

Matching crankshaft bearing shells to bearings in retaining frame
t  On used and machined crankshafts, the main bearing journals must be measured in order to select the correct bearing shells.
t  Any markings still visible on a machined crankshaft are invalid.
t  Allocate the bearing shells according to the measured diameter of the crankshaft main bearing journals as follows:
   
Main bearing journal ØColour code of bearing shells for retaining frame
Dimension (in mm)RedYellowBlue
Basic dimension
65 → Note		64.978 … 64.97264.972 … 64.96564.965 … 64.958
Repair undersize
64.75 → Note		64.728 … 64.72264.722 … 64.71564.715 … 64.708

1)  The colour coding of the bearing shells does not indicate whether the bearing shells are for a new crankshaft or for a machined crankshaft.
   

Crankshaft dimensions > < Allocation of main bearing shells for new crankshafts