Examination
1. Set the piston of the first cylinder to the position 45° before TDC.
2. Lock the camshafts through the holes in the first bearing caps using four rods (1) with a diameter of 6.5 mm.
Adjustment (position 45° before TDC)
1. Remove the upper sliding lever (2a).
2. Remove the timing chain tensioner.
3. Turn the camshafts in the direction of engine rotation, starting with the right exhaust camshaft (1). Start adjusting from the left exhaust camshaft (4), the loose part of the chain (arrows) near the tensioner should move by turning the camshafts (1), (2) and (3).
4. Set the left exhaust camshaft to the reference position using the key (3). Install the timing chain on the sprocket and lock the camshaft with the rod.
5. Set the left intake camshaft to the reference position using the key (3). Install the timing chain on the sprocket and lock the camshaft with the rod. The camshaft is in the "lag" position.
6. Set the right intake camshaft to the reference position using the key (3). Install the timing chain on the sprocket and lock the camshaft with the rod (1). The camshaft is in the "lag" position.
7. Set the right exhaust camshaft to the check position using the key (3). Install the timing chain on the sprocket and lock the camshaft with the rod (1).
(Text republished from the website: MercedesMAN.ru)
8. Further installation is carried out in the reverse order of removal.