Cylinder Head Cover — Removal and Installation (BMW 3 Series E46)

Note: When installing the cover, a new gasket may be required (see text).

Engine M43TU

Removal

1. At the rear of the engine compartment, remove the cabin filter cover by turning its latches 90° counterclockwise. Remove the filter (if necessary, see chapter 1).

2. Unfasten the four fasteners of the box for laying the wires and remove the sleeves with wires from the box (Fig. 4.2).



3. Unscrew the four screws and pull the cabin filter housing forward (Fig. 4.3).



4. Disconnect the crankcase ventilation hose from the cylinder head cover (Fig. 4.4). Unscrew the cover mounting bolts and remove it from the cylinder head. Remove the gasket.

Installation

5. Thoroughly wipe the mating surfaces of the cylinder head and cover.



6. Check the condition of the rubber seals of the cover mounting bolts. Replace them if necessary. Put the seals and washers on the bolts (Fig. 4.6).



7. Inspect the cover gasket and replace if necessary. Insert the gasket into the cover.

8. Apply a small amount of sealant to the surface of the cylinder head where the upper camshaft chain cover contacts it (Fig. 4.8).



9. Install the cover onto the cylinder head, aligning the protrusion on the gasket with the cutout on the back of the cylinder head.

10. Replace the cover mounting bolts and tighten them securely.

Engine N42

Removal

11. Unscrew the two nuts securing the upper plastic engine cover. Lift the front edge of the cover and pull it forward.

12. At the rear of the engine compartment, remove the cabin filter cover by turning its latches 90° counterclockwise. Remove the cover and pull out the filter.



13. Unfasten the four fasteners of the cable management box and remove the sleeves with wires from the box (see fig. 4.2).

14. Remove the four screws and pull the cabin filter housing forward (see fig. 4.3).

15. In the rear left corner of the engine compartment, lift up the sealing harness, release the trim from the clips and pull it forward slightly (Fig. 4.15).



16. Unscrew the two slotted head screws that secure the heater inlet housing and remove the housing (Fig. 4.16).



17. Unscrew the oil filler plug. Align the marks on the hole neck and the filler neck (Fig. 4.17). Squeeze the filler neck in a direction perpendicular to the marks and pull the neck out of the filler neck.



18. Remove the plastic ignition coil cover from the rubber bushings.



19. Pry up the right edge of the ignition coil covers (above the candles) and disconnect the coil connectors (Fig. 4.19). After this, pull the coils off the spark plugs.



20. Disconnect the electrical connectors of the valve timing motor and the eccentric position sensor, then release the ignition coil wire harness from the fasteners on the cylinder head cover and move the harness to the side. Pay attention to the two ground terminals on the cylinder head cover (Fig. 4.20).



21. Squeeze the crankcase ventilation hose connection to the cylinder head cover and pull the hose off the cover.

22. Unscrew the two screws and remove the eccentric position sensor flange (Fig. 4.22).



23. Loosen the cylinder head cover mounting screws and remove the cover (Fig. 4.23). Note that the screws are of different lengths - do not mix them up when assembling. If the cover gasket is in good condition, it can be reused. If not, replace it.

Note: At the time of writing, the gasket was only available with the cover and screws. For more up-to-date information, please contact your BMW dealer.

24. If necessary, remove the spark plug sealing tubes from the cylinder head.

Installation

25. Install the spark plug tube sealing rings. Moisten them with engine oil and push them into the cylinder head holes (Fig. 4.25).



26. Apply a thin coat of Drei Bond sealant (can be purchased from a dealer) in the areas shown in Fig. 4.26 on the front and rear sides of the cylinder head.



27. Place the gasket on the cylinder head cover and install the cover in place. Screw in the cover mounting screws and tighten them by hand for now.



28. Wet the sealing ring of the eccentric position sensor flange, insert the flange, screw in the screws and tighten them by hand for now.

29. Make sure that the gasket under the cover has not shifted and tighten the screws securing it to the required torque in a diagonal sequence.

30. Securely tighten the eccentric position sensor flange mounting bolts.

31. Otherwise, assembly is carried out in the reverse order of disassembly.