Variable Valve Timing Actuator: Adjustments

Variable Valve timing unit, checking and adjusting

Special Tools:
999 5451
999 5452

Note: This procedure must be carried out with precision as any deviation could generate a fault symptom.

Installing the crankshaft adjustment tool





- Remove the mounting screws for the starter motor. Pull out starter motor and place it to one side. Remove blind cover plug from the hole for the adjustment tool. Turn the crankshaft clockwise slightly. Install tool 999 5451. Ensure that the tool bottoms out against the cylinder block.

Aligning the crankshaft

- Turn the crankshaft counter-clockwise until it stops against the adjustment tool. Check that the marking on the the crankshaft timing gear pulley corresponds to the marking on the oil pump.

Installing the variable valve timing unit on the camshaft

Note: Oil the center screw before installation





- Push on the variable valve timing unit/gear pulley on the camshaft. Install the center (1) which secures the variable valve timing unit to the camshaft. Tighten slightly.

- Slacken off, but do not remove the screws (2) which secure the timing gear pulley to the variable valve timing unit. Turn the timing gear pulley until the screws at the oval holes are in the center position. Tighten the screws (2) slightly.

- Turn the variable valve timing unit clockwise to its limit position so that the unit is in its end position. Position the upper timing cover.





- 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.

Installing the timing belt





Note: Variable valve timing units do not have return springs and are easily thrown out of position when the camshaft belt is installed. Check that the markings align.

Install the timing belt in the following order:

• Idler pulley
• Intake cam
• Exhaust cam
• Water pump
• Tension pulley

Tensioning of Timing belt





- This adjustment is to be made with a cold engine. A suitable temperature is approximately 20°C/68°F. At a higher temperature, for example with a warm engine or warmer ambient temperature, the needle is further to the right. The illustration above shows the position of the indicator when aligning the timing belt tensioner at approximately 20°C/68°F.

Note: There are two different tensioners depending on model year.

- Fix the belt tensioner center screw in position and turn the belt tensioner eccentric clockwise until the tensioner indicator passes the marked position and reaches the end position. Then turn the eccentric back so the indicator reaches the marked position illustrated. Tighten the center screw.

- Check that the indicator is in the correct position.

Tightening





- Slacken off the 3 screws for the timing gear pulley slightly (applies to both timing gear pulleys). Install the center plug in the variable valve timing unit. Hold the center plug at 25Nm at the same time as tightening the 3 screws on the camshaft timing gear pulley. Tighten the 3 screws on the timing gear pulley for the intake camshaft. This is to ensure that the variable valve timing (VVT) unit is in its end position when the timing gear pulley is tightened.

Final Check





Remove:
999 5452 from the rear of the camshafts
999 5451 Install new plugs with new sealing washers. Tighten.

- Checking the markings and belt position. Position the upper timing cover. Turn the crankshaft 2 rotations. Check that the markings on the crankshaft and timing gear pulleys correspond. Re-install the upper timing cover.