Cylinder Head and Cover Overview

Cylinder Head and Cover Overview

• Coat all contact surfaces between the hydraulic lash adjusters, the roller rocker arms and the lubricating surfaces on the camshaft with oil before installing the "replacement cylinder head".

• The plastic protectors installed to protect the open valves must only be removed immediately before installing the cylinder head.

• Replace the cylinder head bolts.

• It is necessary to replace all the engine coolant when the cylinder head or cylinder head gasket are replaced.






1 Bolt

• 10 Nm

2 Cylinder Head Cover

• With the pressure regulator valve for the crankshaft housing ventilation.

• Tightening sequence, refer to => [ Cylinder Head Cover Bolt Tightening Sequence ].

• Removing and installing, refer to => [ Cylinder Head Cover ] Cylinder Head Cover.

3 Cylinder Head Cover Gasket

• Replace if damaged or leaking.

4 Crankcase Ventilation Hose

• To the intake manifold.

5 Oil Fill Cap

6 Seal

• Replace if damaged or leaking.

7 Bolt

• 10 Nm

8 Wire Bracket

9 Seal

• Removing and installing, refer to => [ Chain Compartment Cover Seal ] Service and Repair.

10 Wire Bracket

11 Chain Compartment Cover

• Removing and installing, refer to => [ Chain Compartment Cover ] Service and Repair.

12 Bolt

• 2 Nm

13 Camshaft Adjustment Valve 1 (N205)

• Check using the vehicle diagnostic tester.

14 O-ring

• Replace if damaged.

• For the camshaft position sensor (item 16) no replacement part available.

15 Bolt

• 10 Nm

16 Camshaft Position Sensor (G40)

17 Transport Strap

18 Bolt

• 25 Nm

19 Cylinder Head Gasket

• Replace.

• After replacing, replace the entire amount of coolant.

20 Cylinder Head

• Removing and installing, refer to => [ Cylinder Head ] Cylinder Head.

• Checking the cylinder head for warpage. Refer to => [ Checking the Cylinder Head for Warpage ].

• It is not permitted to rework the sealing surface.

• With the adapter (coolant pipe connection) pressed in.

- If necessary, remove any coolant deposits using a copper wire brush or fine sandpaper (minimum 100 grit).

- If the adapter (pipe connection) is worn, replace it using liquid locking fluid (D 000 600 A2).

21 Cap

• Only on engines with the Secondary Air Injection (AIR) system.

• Engines with the AIR system, refer to => [ Secondary Air Injection System Overview ] Service and Repair.

22 Gasket

• Always replace.

23 Bolt

• 40 Nm + 180° (1/8) additional turn.

• Always replace.

• Follow the loosening and tightening sequence. Refer to => [ Cylinder Head ] Cylinder Head.

24 Wire Bracket

• For the heated oxygen sensor (G39).

Cylinder Head Cover Bolt Tightening Sequence





Checking the Cylinder Head for Warpage





- Check the cylinder head in several places for warpage using a straight edge and a feeler gauge.

• Maximum permissible warpage: 0.05 mm

If this value is exceeded, the cylinder head must be replaced. It is not permissible to rework the sealing surface.