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

WARNING: This page is about a different variant/trim than selected.

Special tools required:

11 4 481
11 9 551

Necessary preliminary tasks:

Remove cylinder head cover.
Remove adjusting unit for inlet camshaft. See Removing and installing/replacing inlet and exhaust adjustment units .
Remove intermediate lever .
Remove exhaust camshaft .

IMPORTANT: The screws of the bearing bridge must not be opened.
Releasing the bearing bridge will result in damage to the cylinder head.

Fig 1: Screws Of Bearing Bridge Must Not Be Opened; Releasing Bearing Bridge Will Result In Damage To Cylinder Head

Courtesy of BMW OF NORTH AMERICA, INC.

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 tidy and orderly fashion.

Remove camshaft (6).

Installation:

Clean all bearing points and lubricate with oil.

Check plain compression rings for damage.

Fig 2: Identifying Screws Of Bearing Caps And Camshaft

Courtesy of BMW OF NORTH AMERICA, INC.

Metal rectangular compression ring:

IMPORTANT: Plain rectangular compression rings (1) can easily break.

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

The compression rings have catches at the joint.

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

Fig 3: Replacing Compression Rings

Courtesy of BMW OF NORTH AMERICA, INC.

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

Installation note:

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

Plastic rectangular compression ring:

Installation note:

The plastic plain rectangular compression ring is maintenance free and does not have to be replaced.

Insert plastic rectangular compression ring (1) into groove of intake camshaft (2) (see arrow in illustration).

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

Fig 4: Inserting Plastic Rectangular Compression Ring Into Intake Camshaft Groove

Courtesy of BMW OF NORTH AMERICA, INC.

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

Fig 5: Identifying Plastic Rectangular Compression Rings

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Both camshafts have different identifications.
Mixing up the two camshafts will result in engine damage.
EX Exhaust camshaft.
IN Inlet camshaft.

Fig 6: Identifying Camshaft Identification (IN And EX)