Replacing Tensioning Rail

Reference Image for procedure.





NOTE:
In order to achieve better guidance of the timing chain, the plastic support has lateral guide bars (arrows).
The plastic support is also fixed differently; in this way the support is prevented from slipping off the tensioner blade

TENSIONING RAIL REPLACEMENT
- Remove Cylinder Head Cover.
- Remove Oil Pan.
- Remove Timing Case Cover





- Mark timing chain and crankshaft gear relative to each other.





- Mark timing chain and camshaft timing gear relative to each other.





- Remove timing chain tensioner.





- Unbolt oil pressure pump (if equipped) with lines connected (arrows) and put to one side.





- Unbolt camshaft timing gear (9a),
^ Tightening torque 80 Nm (59 ft lbs).
- Note color markings on camshaft timing gear and crankshaft gear.

NOTE: On vehicles with oil pressure pump remove driving disc sleeve (70).





- Swing tensioner blade (22) for single roller chain inwards and remove from bearing pin (26).





- On engines with double roller chain, pull out bearing pin (26) of the tensioner blade with the impact extractor 116 589 20 33 00 and extension 116 589 03 34 00.
^ To do this cut an M6 thread approx. 10 mm deep on the bearing pin.
- Remove tensioner blade.
- Check plastic support for wear, replace if necessary.





- Insert new tensioner blade and drive home bearing pin up to stop.
- Install chain tensioner.





- Turn crankshaft and check adjusting marking at TDC position of engine.
- The installation proceeds in the reverse sequence of removal.
- Run engine, check for leaks.