Timing Chain Tensioner: Service and Repair

Removing and installing chain tensioner
Removing chain tensioner

Caution: Risk of damaging the timing drive mechanism!
^ Forces from the valve can cause the timing chain to jump over or to tilt.
^ Never twist the crankshaft against the direction of rotation.
^ Remove and install the chain tensioner only in overlapping TDC.
^ Never twist the crankshaft when the chain tensioner is removed.

^ Ignition is off, ignition key is removed.

Note:
^ All spark plugs (except for those on cylinder 3) must be removed to ensure that the relevant dead center can be found more easily.
^ The torque support bracket can remain in place.





1. Remove spark plugs (except those on cylinder 3).





2. Find overlapping TDC of cylinder 1. To do this, insert the ignition rod module of the first cylinder into the corresponding opening in the valve cover and press in firmly.





- Twist the crankshaft in the direction of motion until the ignition rod module comes out again with an audible plop. Then twist the crankshaft until the fixing bore on the crankshaft belt pulley is aligned with the bore in the timing case cover. The engine is now located in the ignition TDC of cylinder 1.





- Then twist the crankshaft through 360° in the direction of motion. The engine is now located in the overlapping TDC of cylinder 1.





3. Open cable clip -7- of the generator's electric cable and press the cable upwards.





4. Undo chain tensioner and unscrew it by hand.

Installing chain tensioner

Note: If the chain tensioner is removed, the aluminum sealing ring must be replaced.





1. Screw chain tensioner with new sealing ring down by hand and tighten.
Tightening torque: 60 Nm (44 ft. lbs.).





2. Clip in the electric cable of the generator again.
3. To check, turn crankshaft two turns in a clockwise direction.





4. Install spark plugs and covers.





Tightening torques

Refer to Timing Chain Guide; Service and Repair; Procedures.