Removing and Installing/Replacing Right Inlet Camshaft

11 31 034 Removing and installing/replacing right inlet camshaft (N74)

Special tools required:

(cylinder bank 7 to 12)





Important!
Pistons at the top of cylinder 1 and 6 are a damage hazard when cylinder 1 is in firing TDC position!
For safety reasons, crank engine back at central bolt by approx. 30°.





Necessary preliminary tasks:
^ Remove left cylinder head cover.
^ Check timing.
^ Remove left inlet adjustment unit.





Release bolts of camshaft bearings in sequence (1 to 14) in 1/2 turns.

Set down all bearing caps in a tidy and orderly fashion on special tool 11 4 480.

Remove intake camshaft in upward direction.





Important!
Used rocker arms (1) may only be reused in the same position.

Note:
Rocker arms (1) are freely accessible after inlet camshaft has been removed.

Do "not" remove rocker arm (1) on intake side.





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

Press compression ring (1) on one side into groove, pull up on other side and remove catch.

Carefully pull plain rectangular compression ring (1) apart and remove towards front.

Ends of compression rings (1) point upwards.

Make sure compression rings (1) are engaged at ends.





Note:
Intake camshaft of cylinder bank 1 to 6 is marked with "E and 16.





Important!
Rocker arms (1) slip slightly when inlet camshaft is fitted.
Make sure rocker arms (1) are secured as illustrated on hydraulic valve clearance compensating elements and on valves.

Align all rocker arms (1) straight.

Installation:
Coat all bearing points with engine oil.

Insert intake camshaft (1) free of tension.





Installation:
Ends of compression rings point upwards or downwards.

Make sure plain rectangular compression rings are engaged at ends.





Important!
Do not mix up the bearing caps of cylinders 1 to 6 and 7 to 12.
All bearing caps are coded and must be installed in the same position.

All bearing caps are marked:

L = Cylinders 1 - 6.

R = Cylinders 7 - 12.

E = Intake side

A = Exhaust side

5 = Designation from 1 to 7





Check roller (1) of bucket tappet for ease of movement.





Installation:
Observe installation lugs of high-pressure carrier and bucket tappet.





Fit all bearing caps

Insert all bolts.

Tighten down bolts in sequence (14 to 1) in 1/2 turns.

Tightening torque: 11 31 1 AZ.





Preload intake camshaft with a open-end spanner (2) towards right.

Note:
Image of exhaust camshaft.





Block intake camshaft with special tool 11 9 893.





Install inlet adjustment units.

Adjust valve timing.

Assemble engine.