Crankshaft Main Bearing: Service and Repair

11 21 531 Replacing all crankshaft main bearings (N14)

Special tools required:







IMPORTANT:
Modified assignment of bearings.
Bearing (1) is at the output end (clutch end)
Determine main bearing colours; the designations on the crankcase and crankshaft are always required and can only determined using the table.







Necessary preliminary tasks:
- Remove crankshaft.







Installation:
Bearing shell (1) with lubricant groove must be fitted in crankcase upper section.
Bearing shell (2) without lubricant groove must be fitted in crankcase lower section (bedplate).







IMPORTANT:
Modified assignment of bearings.
Bearing (1) is at the output end (clutch end)

Bearings (1 to 5).
Bearing (2) is a guide bearing.

IMPORTANT:
Clean sealing surfaces.
Do not clean sealing faces with a metal-cutting tool.

Clean sealing faces with special tool 11 4 470 only.

Insert guide rings (1) in crankcase at bearing block (2) with groove facing outwards.







If necessary, attach with engine oil to crankcase.







IMPORTANT:
Modified assignment of bearings.
Bearing (1) is at the output end (clutch end)

Bearings (1 to 5).

IMPORTANT:
Clean sealing surfaces.
Do not clean sealing faces with a metal cutting tool.

Clean sealing faces with special tool 11 4 470 only.







Bearing classification on crankcase upper half:
Bearing allocation 1-5: the designations on the crankcase and crankshaft are always required.
Refer to the table for the colour code.

Example:
Bearing 1. Letter P
Bearing 2. Letter K
Bearing 3. Letter I
Bearing 4. Letter N
Bearing 5. Letter N







Bearing classification on crankcase upper half:
Bearing allocation 1-5: the designations on the crankcase and crankshaft are always required.
Refer to the table for the colour code.

Example:
Bearing 1. Letter T
Bearing 2. Letter Q
Bearing 3. Letter Q
Bearing 4. Letter R
Bearing 5. Letter R












Crankshaft bearing colours:
BL= Blue.
SW= Black.
Gr= Green.
Ge Yellow.
Or Orange.







Bearing classification on crankcase lower half:
Bearing allocation 1-5: the designations on the crankcase and crankshaft are always required.
Refer to the table for the colour code.

Example:
Bearing 1. Letter P
Bearing 2. Letter K
Bearing 3. Letter I
Bearing 4. Letter N
Bearing 5. Letter N







Bearing classification on crankcase lower half:
Bearing allocation 1-5: the designations on the crankcase and crankshaft are always required.
Refer to the table for the colour code.

Example:
Bearing 1. Letter T
Bearing 2. Letter Q
Bearing 3. Letter Q
Bearing 4. Letter R
Bearing 5. Letter R












Crankshaft bearing colours:
BL= Blue.
SW= Black.
Gr= Green.
Ge Yellow.
Or Orange.







Example: Crankcase upper half:
Combining the dots of the designations of the crankshaft and crankcase produces the following colour combinations.
Bearing 1: The letters (P and T) produce in the crankcase upper half the colour Ge= Yellow with lubricant groove.
Bearing 2: K and Q= Ge= Yellow.
Bearing 3: I and Q= Ge= Yellow.
Bearing 4: N and R= Gr= Green.
Bearing 5: N and R= Gr= Green.







Example: Crankcase lower half:
Combining the dots of the designations of the crankcase and crankshaft produces the following colour combinations.
Bearing 1: The letters P. and T. produce in the crankcase lower half the colour Gr= Green without lubricant groove.
Bearing 2: K and Q= Gr= Green.
Bearing 3: I and Q= Gr= Green.
Bearing 4: N and R= Gr= Green.
Bearing 5: N and R= Gr= Green.







Check spray nozzle (2) for damage, replace if necessary.
Release screw (1).
Tightening torque: 11 11 8AZ. 00 00 Excerpt From Company Standard BMW GS 90003-2
Remove oil spray nozzle (2).

Installation:
Oil spray nozzle (2) is turned when screw (1) is tightened and then rests with its upper corner against crankcase.







Install crankcase lower section.
Assemble engine.