R&R of Camshafts

ATTENTION!
Camshafts could be pre-damaged or broken when removal/installation were performed incorrectly without a fixture. In addition, valves could be bent through contact with the piston crowns when mounting the cylinder head on the crankcase.

Be sure to adhere to installation instructions, use proper special tool and follow sequence.







Prepare special tool 11 3 260 for 4-cylinder engine.







Remove spark plugs.
Position special tool 11 3 260 and screw into spark plug threads.

Tightening torque = 23 Nm







Apply pressure on bearing covers by turning the eccentric shaft.

Release bearing cover.

Installation:
Tightening torque:
M6 screw = 10 Nm
M7 screw = 15 Nm
M8 screw = 20 Nm






Loosen eccentric shaft and remove special tool 11 3 260.

Remove bearing covers and place to one side in order fashion. Remove camshaft.







Installation:
The camshafts are marked with "A" for exhaust and "E" for intake.







Installation:
Install camshafts in such a way that the cam peaks for intake and exhaust valves in cylinder No.1 face each other.







Installation:
The bearing covers are marked with A 1 ... A 5 for the exhaust side and with E 1 ... E 5 for the intake side, readable from the intake side.







Remove complete bearing strips with bucket tappets if necessary.

Brace bucket tappets with special tool 11 3 250.

Lift out complete bearing strip with bucket tappet.



NOTE: Worn bucket tappets may only be reused in the same tappet bore.







Installation:
Note centering sleeves on mounting bolts for bearings and 5.







NOTE: If the cylinder head is replaced because of a mechanical defect (cracks, distortion), the contact surfaces of the bearing strips on the old cylinder head must be checked for distortion with a straightedge.
Max. gap: 0.05 mm.

Also replace the bearing strips if this specification is exceeded.







Installation:
Bearing strips are marked with "A" for the exhaust side or "E" for the intake side.







Installation:
Check bearing points on bucket tappets for signs of wear (scoring).







Installation:
The bucket tappets expand without loading by the camshaft and require some time following installation to compress again. For this reason, fast assembly could cause 'closed" valves to still be open and have contact with the pistons.

Note general instructions for working on the valve train refer to General Information on Valve Timing Work.