Crankshaft: Service and Repair

11 21 500 - Replacing crankshaft (N12)





Special tools required:
- 00 9 120
- 11 4 471
- 11 4 472
- 11 6 251
- 11 6 252
- 23 1 240





Warning!
Rotating components (danger or injury!).

It is absolutely essential to follow the procedure described below and the instructions on handling the special tools.





Important!
Jointing torque and angle of rotation must be observed without fail (risk of damage).





Necessary preliminary tasks:
- Remove engine Removing and Installing Engine.
- Mount engine on assembly stand 11 00 ... Mounting Engine on Assembly Stand.
- Remove vibration damper Service and Repair.
- Removing oil pan Service and Repair.
- Remove oil pump Service and Repair.
- Remove timing chain Service and Repair.
- Remove cylinder head Removal and Replacement.
- Remove flywheel .





Release screws (1).

Tightening torque: 11 13 5AZ.

Remove oil deflector (2).

Remove all pistons Service and Repair.





Drive out cover plates (1) with a cross-chisel (2).





Release screws (26 to 11).

Release screws (10 to 1).





Release crankcase lower half in direction of arrow with a regular screwdriver (2) and an open-end wrench (1) at press-off lug.





Remove both radial shaft seals (1).





Remove crankshaft (1).

Important!
Remove crankshaft with aid of a second person.

Weight of crankshaft approx. 19 kg.

Remove main bearing shells, replace if necessary.





Important!
Do not clean sealing faces with a metal-cutting tool.

Clean sealing faces with special tools 11 4 471 and 11 4 472.





Check guide sleeves (1) for damage and correct seating.





Apply sealing bead (1) to crankcase lower half (see picture) with Loctite 5970 sealing compound (see BMW Parts Service).

Installation Note:
Follow manufacturer's instructions (Loctite).





Apply sealing bead (1) to crankcase upper half (see picture) with Loctite 5970 sealing compound (see BMW Parts Service).

Apply a light coating of engine oil to bearings.





Insert crankshaft (1).

Important!
Rotating component (danger of injury!)

Insert crankshaft with aid of a second person.

Weight of crankshaft approx. 19 kg.





Lubricate all bearings from 1 to 5 with engine oil.

Install crankcase lower half.





Tighten bolts (1 to 10).

Tightening torque: 11 11 1AZ. Specifications

Tighten bolts (11 to 26).

Tightening torque: 11 11 2AZ. Specifications





Tighten bolts exclusively with special tool 00 9 120.

Important!
Jointing torque and angle of rotation must be observed without fail.





To prevent oil leakage, apply a thin coating of Loctite 273 to cover sleeve (1) in area (2).





Drive cover sleeves firmly home with special tool 23 1 240 .





Determine crankshaft axial clearance.

Attach special tool 11 6 252 with magnet.

Set special tool 11 6 251 to zero.

Press crankshaft in direction of rotation up to stop.





Replace radial shaft seal at front.

Replace radial shaft seal at rear.

Assemble engine.