Contents: Removal ⬇ Installation ⬇
Note: The sealing surfaces of the cylinder head cover must not be machined.
Removal
1. Remove the timing chain housing.
2. Remove the camshaft chain sprockets (for more details, see the relevant section in this chapter).
3. Remove the locking device "T10123".
4. Remove the ignition coils with the final power stage "N70", "N127", "N₂91", using a special puller "T10094A".
5. Loosen the cylinder head cover mounting bolts crosswise from the outside to the inside and remove them.
6. Carefully remove the cylinder head cover, tapping it lightly, if necessary, with a rubber mallet in an upward direction (the cylinder head cover sits on centering pins).
Caution: When working with the seal remover and degreaser, wear protective gloves and goggles.
7. Remove any remaining sealant on the cylinder head and cylinder head cover using a seal remover.
Note: There must be no sealant residue left in the cylinder head.
8. Loosen and remove the camshaft installation screws in the indicated sequence.
9. Carefully remove the camshaft bearing caps.
10. Carefully remove the camshafts upwards and place them on a clean surface.
Installation
Note: The intake camshaft boss must be positioned in the bore for the Hall sensor.
1. Lubricate the camshaft bearings on the cylinder head cover and on the camshaft caps with a continuous layer of grease (G 052 735 A2).
2. Carefully insert the camshafts into the cylinder head cover.
3. Install the camshaft bearing caps.
4. Insert the camshaft installation screws in the indicated sequence and tighten them by hand.
5. Make sure that the camshaft bearing caps do not jam. Tightening torque: 10 Nm + tighten an additional 90° (¼ turn).
6. Check and ensure that the camshafts rotate freely in their bearings.
Note
- Check and ensure that there are no flammable or lubricating materials on the mating surface of the cylinder head cover.
- Avoid any piston being at top dead center. When the camshaft turns, the valves may hit a piston at TDC.
7. Cut off the nozzle of the sealing agent (sealant)with scissors (AMV 174 004 01) at the front mark (nozzle diameter – no more than 2 mm).
8. Apply a thin, even layer of sealant to the clean sealing surfaces of the cylinder head. The sealant bead should be 2-3 mm thick. In places where there are bolt holes, apply the sealant on the inside.
Note.
- The thickness of the track sealant must not exceed 3 mm, as this will cause excess sealant to enter the lubrication channels and cause engine damage.
- The cylinder head cover must be installed within 15 minutes of applying the sealant.
8. Ensure that all rocker arms are correctly seated on the ends of the valve stems (1) and on the corresponding hydraulic compensators (2), as shown in the figure below.
9. Carefully install the cylinder head cover perpendicularly from above onto the centering pins (arrows) in the cylinder head, as shown in the figure below.
10. Install new mounting bolts and tighten them evenly crosswise from the inside of the cover to the outside. Make sure that the cylinder head cover is not warped during installation. Tightening torque of mounting bolts: 10 Nm + turn an additional 90° (¼ turn).
11. Remove any sealant that has squeezed out, especially in the area of the timing chain housing.
Note: After installing the cylinder head cover, allow the seal to dry for approximately 30 minutes.
12. Further installation is carried out in the reverse order of removal.
