M43TU engine
Note. If the pulley hub is removed, then assembly will require a new bolt and a torque wrench capable of generating a torque of 330 Nm.
Withdrawal
1. Remove the belt (belts) accessory drive as specified in chapter 1. If necessary, remove the A/C compressor pulley.
2. On some engines, the pulley and damper are a separate assembly that is attached to the crankshaft hub, while on other engines, the pulley with damper and hub are a single unit, mounted on the shaft (pic. 5.2).
3. On models with a separate pulley from the hub, unscrew the pulley mounting bolts and remove it from the hub. If necessary, hold the shaft from turning by the head of the hub mounting bolt.
4. On models where the pulley with the damper and the hub form a single unit, the hub mounting bolt will have to be unscrewed. The bolt must also be unscrewed on a model with a separate hub, if the hub for some reason needs to be removed from the shaft.
Attention! The hub bolt is tightened with great force. To fix the shaft from turning, a special tool is required. do not try to use the wrong tool or improvised means for this. Most likely, in this case, you will be injured or damage the engine.
5. Make a device for fixing the shaft from rotation. A suitable fixture can be made from two pieces of steel strip connected by a large bolt. Screw the fixture to the hub with the pulley-to-hub bolts. A genuine tool for this purpose can be obtained from your BMW dealer (pic. 5.5).
6. Loosen the hub bolt. Keep in mind that the bolt is tightened with considerable force.
7. Turn out a bolt and remove a washer. Do not reuse the bolt - replace it with a new one.
8. Remove the hub from the nose of the shaft. If the hub cannot be removed by hand, use a puller.
9. If the segment key does not hold well in the toe of the shaft, remove it as well.
Installation
10. On the model with a single unit pulley - damper - hub (or on a split unit model if the hub was removed for some reason) before installing the hub on the shaft, it is advisable to take the opportunity and replace the front seal of the engine crankshaft in the lower chain cover (see paragraph 6).
11. On the model with a single unit pulley - damper - hub (or on a split unit model if the hub was removed for some reason) perform the operations starting from the next step. Otherwise, go to step 17.
12. Insert the key into the groove of the toe of the crankshaft. Align the groove of the hub with the key and slide the hub onto the shaft.
13. Secure the hub with a new bolt and washer.
14. Screw the anti-rotation device to the hub, as in disassembly, and tighten the bolt to the required torque.
15. Next, on a model with a single pulley - damper - hub assembly, perform the operations starting from step 18.
16. Remove the crankshaft retainer and install the pulley with damper in its place, making sure that the hub locating pin enters the corresponding hole in the pulley.
17. Screw in bolts of fastening of a pulley and tighten them the demanded moment.
18. Install the belt (belts) accessory drive as specified in chapter 1.
N42 engine
Note. If the pulley hub is removed, the assembly will require a new bolt and a torque wrench capable of generating a torque of 300 Nm.
Withdrawal
19. Remove the belt (belts) accessory drive as specified in chapter 1.
20. Turn out three bolts and remove a pulley with a damper from a nave. Hold the crankshaft from turning by the head of the hub bolt (pic. 5.20).
21. To remove the pulley, unscrew the central bolt.
Attention! After loosening the hub bolt, the chain drive sprocket, oil pump and balance shafts will no longer be clamped on the shaft and will be able to rotate independently of it. Therefore, when releasing the hub bolt, fix the crankshaft and camshaft in the installation position as indicated in paragraph 3.
Attention! The hub bolt is tightened with great force. To prevent the crankshaft from turning, a special tool is required, which can be obtained from a BMW dealer. Do not attempt to use an unsuitable tool or improvised means for locking. Most likely, in this case, you will be injured or damage the engine.
22. Make a device for fixing the shaft from rotation. A suitable fixture can be made from two pieces of steel strip connected by a large bolt. Screw the fixture to the hub with the pulley-to-hub bolts.
23. Loosen the hub bolt. Keep in mind that the bolt is tightened with considerable force.
24. Turn out a bolt and remove a nave from a sock of a cranked shaft. When assembling, the bolt must be replaced with a new one. Since the hub is removed, take the opportunity to replace the front crankshaft seal in the lower chain cover at the same time (see paragraph 18).
Installation
25. Installation is carried out in the reverse order of removal, subject to the following notes.
- A) Adjust the balance shafts as indicated in paragraph 16.
- b) Tighten all fasteners to the required torque, if specified.