Cylinder Head Assembly: Service and Repair: Overview

Overview

Note: Always replace the cylinder head bolts.
When performing repairs, replace seals, gaskets, self-locking nuts and bolts which have a specified tightening angle.
The hose connectors and hoses of charge air system must be free of oil and grease before assembling.
When installing an exchange cylinder head with the camshafts installed, the contact surfaces between bucket tappet and cam running surface must be oiled after installation of the cylinder head.
The plastic protectors fitted to protect the open valves must only be removed immediately before installing the cylinder head.
When installing a new cylinder head or cylinder head gasket, drain off all the old coolant and re-fill with new coolant.
Cylinder heads which have cracks between the valve seats or between valve seat inserts and the spark plug thread can be used further without reducing service life, provided the cracks do not exceed a maximum of 0.3 mm in width, or when no more than the first 4 turns of the spark plug threads are cracked.

Part I - Cylinder head components






1. Cylinder head gasket
Replacing
Refer to, Removing cylinder head.
Installation position: Part No. to cylinder head
After replacing, fill with fresh coolant

2. Cylinder head
Check for distortion Refer to, Fig. 1
Reworking dimension Refer to, Fig. 2
After replacing, fill with fresh coolant

3. Oil deflector
Note installation position

4. Cylinder head bolt
Always replace
Note sequence when loosening
Note sequence when tightening

5. Cylinder head cover
Removing and installing

6. Ignition coil
7. Cap

8. Gasket
Replace if damaged or leaking

9. 10 Nm
First tighten inner nuts
Tighten outer nuts diagonally

10. Cylinder head cover gasket
Replace if damaged or leaking
Before installing gasket apply "AMV 174004 01. to sealing points Fig. 3 and Fig. 4

11. Gasket
Always replace

12. Combi valve for secondary air inlet
With screw connection

13. 10 Nm

14. Coolant flange
With coolant temperature sender

15. 10 Nm

16. O-ring
Always replace

Part II - Intake manifold components






1. Gasket
Note installation position
Always replace

2. 10 Nm
3. 10 Nm

4. O-ring
For injector
Always replace

5. Fuel rail
With injectors

6. Top coolant pipe
7. 10 Nm
8. 10 Nm

9. O-ring
For top coolant pipe
Always replace

10. 10 Nm
11. Intake manifold
12. 20 Nm

13. Support
For intake manifold

Fig. 1 Check cylinder head for distortion.






- Use knife edge, straightedge and feeler gauge to measure at several points.
Maximum permissible distortion: 0.1 mm

Fig. 2 Reworking dimension for cylinder head






Reworking the cylinder head (shaving) is only permitted down to minimum dimension -a-.
- Minimum dimension -a- = 139.20 mm

Fig. 3 Seal connections between double bearing cap and cylinder head






- Apply a small quantity of sealant AMV 174 004 01 to sides of joints arrows- on upper sealing surface of cylinder head.

Fig. 4 Seal connections between camshaft adjuster and cylinder head






- Apply a small quantity of sealant AMV 174 004 01 to sides of joints arrows- on upper sealing surface of cylinder head.