11 21 531 Replacing all main crankshaft bearing shells (N74): Notes

Necessary preliminary tasks: 

• Remove CRANKSHAFT 

Fig 1: Identifying Main Bearing Cap Punched Number

Courtesy of BMW OF NORTH AMERICA, INC.

The letters denote the bearing shell classification for the relevant bearing position from 1 to 7 (main bearing cap)  .

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color coding on crankshaft 1 to 57

Y= yellow

G= green

V= violet

Fig 2: Identifying Bearing Shell Classification For Relevant Bearing Position From 1 To 7 (Main Bearing Cap)

Courtesy of BMW OF NORTH AMERICA, INC.

The letters denote the bearing shell classification for the relevant bearing position from 1 to 7 crankcase  .

The letters are located on the transmission end in the V-chamber.

The first letter on the left applies to the first bearing position at the front on the timing chain drive.

Color assignment in crankcase 1 to 7.

Y= yellow

G= green

V= violet

Fig 3: Identifying Bearing Shell Classification For Relevant Bearing Position From 1 To 7 (Crankcase)

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Install main bearing shells (1) with lubrication groove in crankcase.

Install main bearing shells (2) without lubrication groove in the main bearing caps.

Fig 4: Identifying Main Bearing Shells With Lubrication Groove And Main Bearing Shells Without Lubrication Groove

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Fig 5: Identifying Thrust Washers Discs Surface On Main Bearing Cap Number 4

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Unscrew thread support bushings in main bearing caps.

Fig 6: Unscrewing Thread Support Bushings In Main Bearing Caps

Courtesy of BMW OF NORTH AMERICA, INC.