Checking Camshafts (Timing) - Engine Removed
Checking Camshafts (Timing) - Engine Removed
Tools
Item A - D:
Item A - B:
Checking Camshafts
The following preliminary work must be carried out:
- Remove engine.
- Remove rear muffler.
- Remove the oil container.
- Remove generator.
- Remove coolant guide housing.
1. Cylinder bank 1 - 3: Undo fuel collection pipe with injection valves and remove holder for turbochargers.
2. Cylinder bank 4 - 6: Undo holder for turbochargers and remove bypass flap control box on turbocharger.
3. Remove ignition coils. Remove electrical plug of the ignition coils, unscrew 2 cylinder screws (hexagon socket) M6 x 25 of each and pull ignition coils out of spark-plug recess.
4. Remove 6 spark plugs.
5. Remove oil extraction pump and closure cap. The oil extraction pump flange must be held with a wrench when the oil line on the pump is loosened. Subsequently unscrew the three fastening screws of the oil extraction pump and the three fastening screws of the closure cap, then lever off the two components.
6. Remove solenoid hydraulic valve for valve lift adjustment. To do so, remove plug, unscrew both hexagon-head bolts M6 x 25 and remove with the holder. Subsequently remove the valve.
7. Remove camshaft housing cover. Unscrew the 15 hexagon-head bolts M6 and remove the camshaft housing cover. If this is stuck, it can be loosened by gently tapping with a plastic hammer.
8. Fit auxiliary chain tensioner for both cylinder banks. Unscrew two hexagon-head bolts M6 on each chain tensioner cover and remove the covers with the chain tensioner. Subsequently screw on both auxiliary chain tensioners and then apply pretension using the hexagon-head bolt until the first ring on the piston just disappears from view.
9. Fit dial gauge. A dial gauge is affixed to the first cylinder on cylinder bank 1 - 3 using the universal dial gauge holder. Extend the probe of the dial gauge until it is certain that measurement on the piston crown is possible.
10. To set the timing, the respective cylinder side must be positioned to overlapping TDC. For this purpose, turn the engine at the belt pulley of the crankshaft (in operating direction) until the maximum defection (reversing point) is attained on the dial gauge. The cams of the 1st cylinder point towards each other -Figure 10.1-, the cams of the 4th cylinder point away from each other (each points towards cylinder head outer wall) -Figure 10.2-.
Figure 10.1: Overlapping TDC of cylinder 1
-1- Exhaust camshaft
-2- Inlet camshaft
Figure 10.2: Overlapping TDC of cylinder 4
-2- Inlet camshaft
-1- Exhaust camshaft
NOTE: Camshaft adjusting element must be positioned to the left-hand stop. Use special tool holding wrench No. 9653
11. Turn camshaft adjusting element of the inlet camshafts to its left stop. Use special tool holding wrench No. 9653 to turn the actuating element of the inlet camshaft counter-clockwise until it meets the stop.
NOTE: Tighten the screws for the adjustment device only slightly. It must be possible to move the frame easily by hand.
12. Fit adjustment devices. Use two screws to fasten the frame of both staking tools at the end of the cylinder bank (clutch side) on the sealing surface for the valve cover. Tighten screws by hand only.
13. Insert holding keys. Insert the holding keys No. 9661/1 into the frame according to their identification and then fasten them with two fastening screws to prevent them from dropping.
Adjustment device of cylinder bank 4 - 6
NOTE:
- If the timing setting is correct, it must be possible to insert the appropriate holding key No. 9661/1 into the slot of the camshaft without using much force.
- Set the timing if incorrect.
Correctly set camshafts
14. Turn the engine on the belt pulley of the crankshaft by 360 degree clockwise so that the second cylinder side can be checked. (Observe maximum defection of dial gauge indicator or TDC position).
NOTE: Camshaft adjusting element must be positioned to the left-hand stop! Use special tool holding wrench No. 9653
15. Position the holding keys No. 9661/1 of the corresponding cylinder bank. The holding keys must slide easily into the camshaft slot.
16. Remove the adjustment devices and the dial gauge.
17. Remove the auxiliary chain tensioner. To do this, relieve the auxiliary chain tensioner and loosen the two fastening screws.
18. Reinstall chain tensioner. Insert the chain tensioner into the chain housing in accordance with its identification, then fit the chain tensioner cover with a new seal. Tighten the hexagon - head bolts M6 to 10 Nm (7.5 ftlb.).
19. Install camshaft housing cover. Apply a silicone bead of a maximum 1.5 mm -Figure- (drying time of sealant approx. 5 mm). Put on the camshaft housing cover and tighten the 15 fastening screws from the inside with tightening torque.
Tightening torque of the hexagon-head bolt M6 (8.8) 10 Nm (7.5 ftlb.)
20. Install solenoid hydraulic valve for valve lift adjustment. Put on holder with both hexagon-head bolts M6 x 25 and tighten the screws with tightening torque.
Tightening torque of the hexagon-head bolt M6 (8.8) 10 Nm (7.5 ftlb.)
21. Fit the closure cap and the oil extraction pump with new 0-rings. Tighten the hexagon-head bolts: 3 M6 x 20 for the closure cap and 3 M6 x 35 for the oil extraction pump to tightening torque.
Tightening torque of the hexagon-head bolt M6 (8.8) 10 Nm (7.5 ftlb.)
22. Fit four new closure caps (green) for camshaft housing cover in dry state.
23. Install spark plugs.
Tightening torque of new spark plug 30 Nm (22 ftlb.); used spark plugs 25 Nm (19 ftlb.)
24. Install ignition coils. Insert ignition coils in spark-plug recess. Position 2 pan-head screws (hexagon socket) M6 x 25 and tighten with tightening torque. Connect cable plug.
Tightening torque of pan-head screw M6 10 Nm (7.5 ftlb.)
NOTE: Replace fastening nuts for holder of turbocharger
25. Cylinder bank 1 - 3: Install fuel collection pipe with injection valves and holder for turbochargers.
26. Cylinder bank 4 - 6: Fit holder for turbochargers and install bypass flap control box on turbocharger.
Tightening torque of fastening nut M8 25 Nm (19 ftlb.)
27. Install coolant guide housing.
28. Install generator.
29. Install the oil container.
NOTE: Replace fastening nuts for flange of turbocharger rear mufflers.
30. Install rear mufflers
Tightening torque of fastening nut M8 25 Nm (19 ftlb.)