Timing Chain Covers — Removal and Installation (BMW 3 Series E46)

M43TU Engine - Top Cover

Note: When installing the cover, you will need a new gasket and suitable sealant. To install the cover, you will need to screw two studs into the holes of the bolts that secure the cover. In addition, you will need a thin metal plate.

Removal

1. Drain the coolant (see chapter 1).

2. Remove the cylinder head cover as shown in paragraph 4.

3. Remove the camshaft position sensor from the cover (if necessary, see chapter 4A).

4. Remove the clips and remove the wiring from the circuit cover.

5. Remove the thermostat (see chapter 3).

6. Loosen the chain cover mounting screws and remove the cover (Fig. 6.6). Remove the gaskets.



7. Remove the rubber seal from the top side of the lower chain cover.

8. Usually, there is a common gasket installed under the top and bottom covers. If in your case such a gasket is installed and you are not going to remove the bottom cover, cut off the top part of the gasket flush with the top plane of the bottom cover. Cut from the inside out. The gasket for the top cover is supplied separately from the bottom cover in the spare parts.

Installation

9. First, thoroughly clean all mating surfaces.



10. Apply a layer of sealant to the mating surfaces of the cylinder head with the chain housing and covers (Fig. 6.10).



11. Screw in two long pins (or bolts with sheared heads) into the threaded holes of the bolts that secure the top chain cover.

12. Place the new gasket under the top cover on the surface of the chain case. Apply a thin layer of sealant to the top and bottom edges of the gasket (Fig. 6.12).



13. Apply a small amount of sealant to the ends of the grooves under the rubber seal on the top side of the lower chain cover (Fig. 6.13).



14. Insert the rubber seal into the grooves of the bottom cover.



15. To prevent the rubber seal on the bottom cover from shifting when installing the top cover, the manufacturer recommends using tool 11 2 330. The tool can be replaced with a very thin metal plate. The plate must be of such a size that it covers the entire seal.

16. Lubricate both sides of the plate with a thin layer of grease and place the plate on the seal (Fig. 6.16).



17. Place the upper chain cover onto the mounting studs. Secure the cover with the lower outer bolts, tightening them by hand for now.

18. Carefully pull the metal plate out from under the lid.

19. Place the cylinder head cover back in place without the gasket.

20. Screw two M6 bolts with large washers into the front holes of the cylinder head cover (screw in the bolts that secure the cover to the cylinder head, not to the chain cover) (Fig. 6.20).



21. Tighten the cylinder head cover bolts to move the chain cover down until it rests against the cylinder head surface.



22. Tighten the previously installed chain cover bolts to the specified torque.

23. Remove the chain cover mounting studs and replace them with the cover mounting bolts. Tighten the bolts to the specified torque.

24. Unscrew the two M6 bolts of the cylinder head cover. Remove the cover.

25. Reinstall the thermostat (see chapter 3).

26. Install the camshaft position sensor (if necessarysee paragraph 12 of chapter 4A)

27. Install the cylinder head cover as shown in paragraph 4.

28. Fill the cooling system with liquid (see chapter 1).

29. Secure the previously removed electrical wiring to the circuit cover.

M43TU Engine - Bottom Cover

Note: A new gasket and suitable sealant will be required during installation.

Removal

30. Remove the upper chain cover as described above.

31. Remove the accessory drive belt as shown in chapter 1.

32. Remove the bolts and pulley from the water pump. To prevent the pulley from turning, wrap an old drive belt around it and squeeze it tightly.

33. Loosen the bolts securing the crankshaft position sensor to the bracket, remove the sensor and move it to the side (for more detailed information, refer to paragraph 12 of chapter 4A). In order not to damage the sensor, it is better to remove it completely.

34. Remove the wiring and hoses from the cover and move them to the side out of the work area.

35. Remove the crankshaft bearing pulley with damper and hub (see paragraph 5).

36. Remove the bolts securing the lower chain cover (remember their location) and remove the cover (Fig. 6.36). Refer to point 8.





37. First, thoroughly clean all mating surfaces.

38. Note the installation depth of the cuff into the lower chain cover, then remove the cuff.

39. Clean the bore 8 of the cover under the cuff, then insert the new cuff and press it to the previously marked depth. To press the cuff, you can use a piece of pipe or a large socket head, the diameter of which is slightly smaller than the outer diameter of the cuff.

40. Make sure that the cover mounting pins are present in the chain housing.

41. Place a new gasket on the housing mounting surface under the cover. To prevent the gasket from falling off, "glue" it with a small amount of consistent grease. Keep the following in mind:

• a) Install a single gasket under the lower and upper chain covers. Apply a small amount of sealant to the upper end of the gasket.
• b) Install the top chain cover as above. Since a single gasket is installed under both covers, omit any instructions regarding a separate gasket for the top cover. There is also no need to screw in the studs when installing the top cover.

42. Replace the bottom cover, secure it with bolts and tighten the bolts to the specified torque.



43. Install the hub and pulley with damper on the crankshaft (see paragraph 5).

44. Secure the previously removed hoses and electrical wiring to the cover.

45. Install the crankshaft position sensor.

46. Install the pulley onto the water pump shaft and tighten the pulley mounting bolts.

47. Install the accessory drive belt as shown in chapter 1.

Engine N42

49. On these engines, the chain housing is made as a single unit with the cylinder block, without covers.