11 31 094 Removing Hydraulic Chain Tensioner For Timing Chains on Left Side

11 31 094 Removing hydraulic chain tensioner for timing chains on left side (S63)

Special tools required:





Warning!
Chain tensioner is pre-tensioned.
Release lock pin only in installed state.
Risk of injury!

Important!
Risk of damage!





The engine must not be cranked when the chain tensioner is removed.
The timing chain may jump.





Necessary preliminary tasks:
^ Remove timing case cover at top left





Crank engine back at central bolt (1) against direction of engine rotation by approx. 90°.

Important!
The timing chain on the chain tensioner becomes the tight end on cranking back.





Do not crank engine without chain tensioner or special tool 11 9 900.

Piston (1) of chain tensioner must be pressed in against oil pressure in housing (see arrow).





If the chain tensioner piston is retracted over its full length, a 3.5 mm drill bit or a suitable lock pin must be positioned.





Release screws (1).

Tightening torque 11 31 5AZ.

Remove chain tensioner (2).

Important!
Risk of injury!





Chain tensioner is under high preload force.

Chain tensioner arrangement:
^ Piston
^ Expansion element
^ Compression spring
^ Housing





Installation:
Replace all gaskets and sealing rings.

Assemble engine.