11 21 531 Replacing All Crankshaft Main Bearing Shells (N63O1)

Special Tools Required: 

• 00 2 590 .
• 00 9 120 .
• 11 6 251 .
• 11 6 252 .

The Letters On The Crankcase and Crankshaft Denote The Bearing Shell Classification for The Relevant Bearing Position From 1 To 5 (Main Bearing Cap).

The Letters From The Crankcase and Crankshaft Are Required To Determine The Bearing Shell Colors.

The First Letter On The Left Applies To The First Bearing Position At The Front On The Timing Chain Drive.

The Bearing Seat (3) Is Designed As Guide Bearing.

Necessary Preliminary Tasks: 

• Remove CRANKSHAFT .

Fig 1: Identifying Number Markings On Main Bearing Caps 1 Through 5

Courtesy of BMW OF NORTH AMERICA, INC.

The Letters On The Crankcase Denote The Bearing Shell Classification for The Relevant Bearing Position From 1 To 5 On The Crankcase.

The First Letter On The Left Applies To The First Bearing Position At The Front On The Timing Chain Drive.

Color Assignment On Crankshaft 1 To 5

Number (3) Is A Guide Bearing.

Fig 2: Identifying Markings for New Bearing Shell Classification

Courtesy of BMW OF NORTH AMERICA, INC.

Observe Crankshaft Construction Stage:

S: Series

B: Repair Stage 1

The Letters On The Crankshaft Denote The Bearing Shell Classification for The Relevant Bearing Position From 1 To 5 In The Main Bearing Cap.

The First Letter On The Left Applies To The First Bearing Position At The Front On The Timing Chain Drive.

Color Assignment On Crankshaft 1 To 5

Number (3) Is A Guide Bearing.

Fig 3: Identifying Color Assignment Markings - Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Installation Note: 

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

Courtesy of BMW OF NORTH AMERICA, INC.

Fig 5: Identifying Surfaces for Thrust Washers On Main Bearing Cap Number 3

Courtesy of BMW OF NORTH AMERICA, INC.

The Letters On The Crankcase Denote The Bearing Shell Classification for The Relevant Bearing Position From 1 To 5 In The Crankcase.

The First Letter On The Left Applies To The First Bearing Position At The Front On The Timing Chain Drive.

Fig 6: Identifying Markings for New Bearing Shell Classification

Courtesy of BMW OF NORTH AMERICA, INC.

The Letters On The Crankshaft Denote The Bearing Shell Classification for The Relevant Bearing Position From 1 To 5 In The Bearing Cap.

The First Letter On The Left Applies To The First Bearing Position At The Front On The Timing Chain Drive.

Example Application: 

Bearing Number 1:

Crankcase Code Letter (Q)  /Crankshaft Code Letter (Q) 

Bearing Shell Crankcase 1 = Green  Bearing Shell Bearing Cap 1 = Green 

Fig 7: Identifying Color Assignment Markings - Crankshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Bearing Number 2:

Crankcase Letter Code (H)  /Crankshaft Letter Code (G) 

Bearing Shell Crankcase 0 = Yellow  Bearing Shell Bearing Cap 0 = Yellow 

Bearing Number 3 (Guide Bearing): 

Crankcase Code Letter (I)  /Crankshaft Code Letter (N) 

Bearing Shell Crankcase 1 = Green  Bearing Shell Bearing Cap 1 = Green 

Bearing Number 4:

Crankcase Letter Code (H)  /Crankshaft Letter Code (E) 

Bearing Shell Crankcase 0 = Yellow  Bearing Shell Bearing Cap 0 = Yellow 

Bearing Number 5:

Crankcase Letter Code (K)  /Crankshaft Letter Code (M) 

Bearing Shell Crankcase 1 = Green  Bearing Shell Bearing Cap 1 = Green 

Turn Back Thread Support Bushing Into Main Bearing Cap.

Fig 8: Turning Back Thread Support Bushing Into Main Bearing Cap

Courtesy of BMW OF NORTH AMERICA, INC.

Checking Main Bearing Clearance 

To Check Crankshaft Bearing Play, Use The Existing Main Bearing Bolts.

Do Not Twist Crankshaft.

Place Special Tool 00 2 590 (Plastigage Model Pg 1) Onto The Oil-Free Crankshaft (See Arrow In Illustration).

Fig 9: Checking Main Bearing Clearance

Courtesy of BMW OF NORTH AMERICA, INC.

Tighten Down All Collar Bolts (M11) of Main Bearing Caps In Sequence 1 To 5 To Joining Torque.

Tightening torque 11 11 1AZ .

Fig 10: Main Bearing Cap Bolts Tightening/Loosening Sequence (N63O1)

Courtesy of BMW OF NORTH AMERICA, INC.

Tighten Down All Collar Bolts (M11) of Main Bearing Caps with Special Tool 00 9 120 with Angle of Rotation.

Fig 11: Tightening Collar Bolts of Main Bearing Caps Using Special Tool 00 9 120

Courtesy of BMW OF NORTH AMERICA, INC.

Remove Main Bearing Cap.

Read Off Main Bearing Clearance At Width of Flattened Plastigage with Assistance of Measurement Scale.

Refer To Technical Data for MAIN BEARING PLAY .

• Remove Plastigage
• Apply A Coat of Oil To New Bearing Shells and Crankshaft
  Fig 12: Measuring Radial Clearance Using Flattened Plastigage

  Courtesy of BMW OF NORTH AMERICA, INC.

Install CRANKSHAFT .

Secure Special Tool 11 6 252 with Magnetic Foot On Crankcase.

Position Special Tool 11 6 251 .

Manually Press Crankshaft (1) All The Way Back.

Set Dial Gauge 11 6 251 To Zero.

Manually Press Crankshaft (1) All The Way Forward.

Check AXIAL PLAY .

Check Guide Bearing Shell, Crankshaft and Crankcase If Necessary.

Fig 13: Securing/Positioning Special Tools

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble Engine.