Cylinder Head, Removing and Installing

Cylinder head, removing and installing

Note:
^ Always replace cylinder head bolts when assembling.
^ Replace self-locking nuts.
^ Always replace bolts that are tightened to a specified angle.
^ Always replace sealing rings and gaskets when assembling.
^ When installing an exchange cylinder head with the camshafts fitted, the contact surfaces between valve lifter 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.





1 - Cylinder head

^ If replaced, replace coolant completely.
^ Checking for distortion Go to Fig. 1
^ Reworking limit Go to Fig. 2

2 - Oil deflector

^ Note installation position: above intake camshaft between No. 1 and No. 2 cylinders

3 - Cylinder head bolt

^ Replace

4 - Cylinder head cover gasket

^ Replace if damaged or leaking
^ Before installing gasket, apply sealant D 454 300 02 to sides of sealing surfaces:

^ Between double bearing cap and cylinder head Go to Fig. 3
^ Between hydraulic chain tensioner and cylinder head Go to Fig. 4

5 - Cylinder head cover

6 - Gasket

^ For ignition coil
^ Replace if damaged

7 - Ignition coil

^ Checking

8 - 10 Nm

9 - Filler cap

10 - Seal

^ Replace if damaged

11 - 10 Nm

12 - Intake manifold gasket

^ Replace

13 - Cylinder head gasket

^ Position: Part No. toward cylinder head
^ If replaced, replace coolant completely.





Fig. 1 Checking cylinder head for distortion

- Use knife-edge straightedge and feeler gauge to measure at several points.

Max. permissible distortion: 0.1 mm





Fig. 2 Cylinder head reworking limit

Reworking cylinder head (shaving) is only permitted down to minimum dimension -a-.

Minimum dimension -a- = 139.25 mm





Fig. 3 Sealing transition points between double bearing cap and cylinder head

- Carefully apply a thin coat of sealant D 454 300 02 to both edges of sealing surfaces between double bearing cap and cylinder head (arrows) using a small screwdriver.





Fig. 4 Sealing points for hydraulic chain tensioner / cylinder head

- Carefully apply a thin coat of sealant D 454 300 02 to both edges of sealing surfaces between hydraulic chain tensioner and cylinder head (arrows) using a small screwdriver.