Variable valve timing unit, checking and adjusting
Special tools:
Since the illustrations in this service information are used for different model years and/or models, some variation may occur. However, the essential information in the illustrations is always correct.
This element must be carried out with precision as any deviation could generate a fault symptom.
Installing the crankshaft adjustment tool
Remove the starter motor mounting screws. Pull out the starter motor and put it aside.
Remove the blind cover plug for the adjustment tool hole. Turn the crankshaft clockwise slightly. Install the adjustment tool 9995451 . Ensure the adjustment tool bottoms against the engine block.
Aligning the crankshaft
Turn the crankshaft counterclockwise to its stop against the crankshaft adjustment tool. Check that the marking on the crankshaft timing gear pulley aligns with the marking on the oil pump.
Installing the camshaft variable valve timing unit
Oil the center screw before installation.
Press the variable valve timing unit/timing gear pulley onto the camshaft. Install the center screw (1) that holds the variable valve timing unit to the camshaft. Tighten slightly.
Loosen but do not remove the screws (2) holding the timing gear pulley to the variable valve timing unit. Turn the timing gear pulley so that the screws at the oval holes are in the center position and then tighten the screws (2) slightly.
Turn the variable valve timing unit clockwise to its stop so that the unit is in its end position. Install the upper timing cover.
Installing the camshaft belt
Undo the center screw and continue turning clockwise until the timing gear pulley marking aligns with the marking on the upper timing cover.
Tighten the center screw in the variable valve timing unit.
Tighten, see: Summary of tightening torques for specific components .
Tensioning the camshaft belt
The variable valve timing units do not have a return spring and are easily dislodged when installing the timing belt. Check that the markings match.
Install the belt in the following order:
- crankshaft
- idler pulley
- intake camshaft
- exhaust camshaft
- water pump
- tensioner pulley.
Tensioning the camshaft belt
This adjustment is done on a cold engine. A suitable temperature is approx. 20°C/68°F. At higher temperatures, for example when the engine is hot or in high ambient temperatures, the gauge needle is further to the right.
The position of the needle, when aligning the camshaft belt tensioner at different engine temperatures, is shown in the illustration.
Carefully turn the crankshaft clockwise until the timing belt is tensioned. The belt must be in tension between the intake camshaft pulley, the idler pulley and the crankshaft.
Hold the belt tensioner center screw secure. Turn the belt tensioner eccentric clockwise until the tensioner indicator passes the marked position.
Then turn the eccentric back so that the indicator reaches the marked position in the center of the window.
Hold the eccentric secure and tighten the center screw. Tighten to 25 Nm .
Check that the indicator is in the correct position.
Tightening
Undo the 3 timing gear pulley screws slightly. Install the center plug in the variable valve timing unit. Tighten following Summary of tightening torques for specific components .
Hold the center plug in place with 25 Nm while the 3 screws on the camshaft timing gear pulley are tightened. See Summary of tightening torques for specific components . This is to ensure that the variable valve timing unit is in its end position when the timing gear pulley is fastened.
Removing the camshaft adjustment tool
Remove the camshaft adjustment tool 9995452 and the crankshaft adjustment tool 9995451 .
Install the plug to the starter motor with a new washer and tighten. See Tightening torque .
Final check
Turn the engine 2 revolutions.
Then check that the belt tensioner indicator is in the center position. If not, it must be adjusted so that the indicator is in the correct position described in a previous work element.