Overhaul

Cylinder head, camshafts, overview





1 - 50 Nm plus an additional 180 degrees

2 - Camshaft sprocket

3 - Seal

^ Replacing.

4 - Cylinder head

5 - Valve guide

^ Checking

6 - Valve stem seal

7 - Valve spring

8 - Top valve spring retainer

9 - Valve keepers

10 - Hydraulic valve play balancing element

^ Do not interchange
^ Lubricate contact surface

11 - Fitted key

^ Check for secure seat

12 - Exhaust camshaft

^ Check radial clearance using Plastigage (roller cam follower removed) wear limit: 0.1 mm
^ Run-out: max. 0.035 mm

13 - Bearing bracket

^ With integrated camshaft bearings
^ Clean sealing surface, reworking is not permitted.
^ Remove old sealant residue.

14 - 8 Nm plus an additional 90 degrees

^ Replace

15 - Camshaft adjuster

16 - 20 Nm plus an additional 45 degrees

^ Replace

17 - Intake camshaft

^ Check radial clearance using Plastigage (roller cam follower removed) wear limit: 0.1 mm
^ Run-out: max. 0.035 mm

18 - Chain tensioner

^ Remove Camshaft adjuster
^ Before removing, secure with Locking Pin T10115

19 - Drive chain

^ Check for wear

20 - 10 Nm

21 - 10 Nm
22 - Phase sensor

23 - Exhaust valve

^ Do not rework, only lapping is permitted
^ Valve dimensions
^ Check valve guides

24 - Intake valve

^ Do not rework, only lapping is permitted
^ Valve dimensions
^ Check valve guides

25 - Sealing cap

^ Replace
^ Removing: When guide frame is installed: Pierce through one side of cover with an awl and pry it out
^ Installing: Without sealant press in with thrust piece 3334 1 to 2 mm deep





Valve dimensions

Note:
^ Intake and exhaust valves must not be refaced by grinding. Only lapping is permitted.