Engine Type M 44.43/44
Check requirements: Belt tension o.k.
Visual check of TDC marks
1. Turn engine in sense of rotation until cylinder no. 1 is at firing TDC
TDC mark on flywheel (center notch) with engine fitted (double-mass flywheel).
Distributor rotor points up.
Camshaft position with cyl. 1 at firing TDC.
With the engine removed, transfer TDC flywheel mark with a color pen to the sensor ring gear.
Set TDC flywheel mark opposite crankcase mark.
Adjusting with dial gauges
2. Align dial gauge with shop-made extension (length 205 mm) to piston pin (cyl. 1). Preload 3 mm.
Align second dial gauge to hydraulic tappet of cyl. 1 inlet valve. The dial gauge must be set up perpendicular to the inlet valve. Preload: 3 mm.
3. Remove distributor rotor and fit camshaft gear with 3 auxiliary bolts (M 5 x 15) to prevent the camshaft gear and the camshaft, respectively, from turning when the central camshaft bolt is undone.
4. Undo central camshaft bolt, using a suitable retainer to keep the camshaft from turning. Rotate engine against the sense of rotation until the camshaft gear is against the stop within the woodruff key groove.
Checking and adjusting the camshaft setting
Printed in Germany - II, 1991
6. Remove oil line from camshaft adjuster. Connect flange (Special Tool 9529) to camshaft adjuster and pressurize (pressure flow approx. 3.0 bar). A consistent supply of compressed air is required since air can escape across a vent hole.
7. Turn engine in sense of rotation until maximum piston stroke is reached.
8. Set dial gauge of hydraulic tappet of cyl. 1 inlet valve to zero.
9. The crankshaft is now rotated from the firing TDC (cyl. 1). Observe dial gauge of cyl. 1 inlet valve at the same time.
Rotate until a stroke of 0.39 ± 0.03 mm is reached.
Do not rotate crankshaft against the sense of rotation.
10. Undo central bolt and auxiliary bolts, making sure the setting of 0.39 ± 0.03 mm on the dial gauge does not change.
11. Continue to rotate the crankshaft slowly until maximum piston stroke on the dial gauge is reached. This crankshaft position corresponds to the cyl. 4 firing TDC setting of the camshafts.
12. Tighten auxiliary bolts and central bolt. Tightening torque of central bolt:
13. To verify the setting, rotate crankshaft by two more turns and check setting.
14. Remove Special Tool and auxiliary bolts and reinstall distributor rotor.
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