11 21 531 Replacing all crankshaft main bearing shells (B48, B46)

Special tools required: 

• 00 2 010

There must be no oil in the blind holes (risk of cracking).

Do not  wash off bolt coating.

Incorrect assembly of the bearing caps will result in damage to the crankcase.

The code letter K  on the crankcase stands for "Kupplungsseite" (German = clutch end).

Installation note: 

Bearing classification from 1 to 3 (bearing cap) and A  to C  (crankcase) possible.

• Bearing color blue
• Bearing color - green
• Bearing color brown

Necessary preliminary tasks: 

• Remove CRANKSHAFT 

Pay attention to the different bearing classification sequences in the crankcase and the bearing caps.

Bearing classification in crankcase: A/B/C 

The code letter (1) K  on the crankcase stands for "Kupplungsseite" (English = clutch end).

The following code letters (5 - 1) describe the bearing positions 5  to 1  from left to right.

Example (see illustration):

Bearing seat 5: 

Code letter B  = green bearing shell with lubricating groove.

Fig 1: Bearing Code Letters

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Bearing seat 4: 

Code letter B= green bearing shell with lubricating groove.

Bearing seat 3: 

Code letter B= green bearing shell with lubricating groove (thrust bearing).

Bearing seat 2: 

Code letter B= green bearing shell with lubricating groove.

Bearing seat 1: 

Code letter B= green bearing shell with lubricating groove.

Fig 2: Bearing Code Letters

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Bearing classification in bearing cap: 1/2/3 

The code numbers (1- 5) describe the bearing positions 1 to 5  from left to right.

Example (see illustration):

Bearing cap 1: 

ID code 1=  bearing shell, blue, without lubricating groove.

Bearing cap 2: 

Code 2=  green bearing shell without lubricating groove.

Bearing cap 3: 

Code 2=  green bearing shell without lubricating groove (thrust bearing).

Bearing cap 4: 

Code 2=  green bearing shell without lubricating groove.

Bearing cap 5: 

Code 2=  green bearing shell without lubricating groove.

Enter code letters and numbers for crankcase and crankshaft

Remove bearing shells 1 to 5.

Fig 3: Oil Bearing Shells

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Place main bearing shell (1) with lubricating groove in crankcase (see arrows).

Observe combination of bearing colors according to the table.

Fig 4: Main Bearing Shell

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Place main bearing shell (1) with no lubricating groove in the bearing cap (see arrows).

Observe combination of bearing colors according to the table.

Fig 5: Standard Main Bearing Shell

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Observe combination of bearing colors according to the table.

Fig 6: Thrust Bearing

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Install CRANKSHAFT .

Check SIDE CLEARANCE .

If necessary, check guide bearing shells, crankshaft and engine block.

Fig 7: Checking Crankshaft Side Clearance

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Rotate crankshaft (1) with special tool 00 2 010 in direction of arrow.

Check CRANKSHAFT coefficient of friction.

Fig 8: Turning Crankshaft Evenly With Special Tool (00 2 010) And (11 6 480)

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