Removing and Installing/Replacing Inlet Camshaft

11 31 025 Removing and installing/replacing intake camshaft (N12)

Special tools required:





Necessary preliminary work:
^ Remove cylinder head cover.
^ Remove adjusting unit for intake camshaft.
^ Remove intermediate lever.
^ Remove exhaust camshaft.





Important!
The screws of the bearing bracket must not be opened.
Releasing the bearing bracket will result in damage to the cylinder head.





Bearing cap (1) marked 5 is a thrust bearing.

Release screws of bearing caps (1 to 5).

Set all bearing caps down in special tool 11 4 481 in a neat and orderly fashion.

Remove camshaft (6).

Installation note:
Clean all bearing positions and lubricate with oil.

Check plain rectangular compression rings for damage.





Metal plain rectangular compression ring:

Important!
Plain rectangular compression rings (1) can easily break.

Only replace plain rectangular compression rings (1) when they are broken.

The plain rectangular compression rings have catches at the joint.

Press plain rectangular compression rings (1) apart upwards and downwards and removed towards front.

Make sure plain rectangular compression rings (1) can move freely.

Installation note:
When intake camshafts are inserted, no joint must point to a separating joint.





Plastic plain rectangular compression ring:
Insert plastic plain rectangular compression ring (1) into groove of intake camshaft (2) (see arrow).

Lightly oil plastic plain rectangular compression ring (1) and rotate in direction of arrow until plastic plain rectangular compression ring (1) is positioned on the intake camshaft.





Check plastic plain rectangular compression ring (1 and 2) for freedom of movement.





Important!
Both camshafts have different identifications.

Mixing up the two camshafts will result in engine damage.

EX Exhaust camshaft.

IN Intake camshaft





Insert camshaft (E) so that IN marking points upwards.

Position intake camshaft (E) so that cams point upwards at an angle.

Attach special tool 11 9 551 to mounting flats.

Make sure plain rectangular compression rings cable can move freely.

Installation note:
Joint of plain rectangular compression rings must not point to a separating joint (risk of breakage!).





All bearing caps are identified from 5 to 10.

Observe pairing numbers (1).





Tighten bearing caps from inside outwards.

Tightening torque: 11 12 7AZ.





Adjust valve timing.

Assemble engine.