Note: If the valve timing is not adjusted, the valve actuator and the crank mechanism do not work in harmony. An incorrectly adjusted valve timing mechanism causes a drop in effective engine power, and in extreme cases can lead to engine failure as a result of a piston hitting a valve that has not yet closed. Adjustment of the gas distribution mechanism for each type of engine is performed differently.
Replacing the toothed belt on five- and six-cylinder engines is only possible with the help of special tools.
On a five-cylinder engine, to remove the toothed belt, you must remove and then reinstall the vibration damper on the crankshaft. This operation is carried out using a special extension 2079 for the torque wrench and counterhold 2084. These tools are not needed when replacing only the cylinder head. 11When replacing the head, the toothed belt in its lower part remains on the crankshaft gear.
As for the six-cylinder engine, in order to adjust the timing mechanism after replacing the toothed belt and dismantling the cylinder head, it is necessary to accurately, using special tools, set the camshaft and crankshaft to TDC.
These difficulties are not peculiar to a four-cylinder engine. No special tools are needed when working on the toothed belt.
Four cylinder engine
1. Set the piston of cylinder No. 1 to the TDC position.
2. Remove the V-belt or ribbed belt.
3. Remove the belt pulley from the crankshaft by unscrewing the mounting bolts with an internal hexagon (not center bolt).
4. Remove the toothed belt guard.
5. Loosen the toothed belt tension and remove it.
6. Install a new toothed belt. If the crankshaft and camshafts have not shifted, then we can assume that the valve drive setting is not knocked down. We recommend to play it safe and check it again.
7. Rotate the toothed belt gear on the camshaft until the mark under the arrow on gear 1 matches the mark on the rear toothed belt guard 2 (see illustration).
If you need to turn the camshaft, then this can be done provided that none of the pistons is at TDC. Otherwise, damage to the valves or pistons will occur.
8. Lay the toothed belt on the gears of the crankshaft and intermediate shaft.
9. Attach the V-belt pulley to the crankshaft with one bolt. At the same time, observe the correct installation of the pulley, which depends on the engine version. In some cases, the belt pulley must lock onto the thrust pin. In other versions, the holes for the pulley mounting bolts are located asymmetrically and therefore the installation of the pulley will be performed correctly if all the holes on the pulley match the holes on the crankshaft.
10. Rotate the crankshaft until the notch on the V-belt pulley is facing up.
11. Align the notch on the countershaft gear with the notch on the V-belt pulley (see arrows in illustration).
12. Apply toothed belt. At the same time, do not allow the position of the gears and pulleys to shift.
13. Tighten the toothed belt.
14. Remove the ignition distributor cover and make sure that the distributor slider faces the notch on the distributor housing. If this is not the case, then remove the distributor mounting bolt.
15. Rotate the distributor until the slider is opposite the notch. If necessary, remove the slider and install it again against the notch.
16. Install the ignition distributor in place and secure with a bolt.
17. Turn the engine two times and check the adjustment.
Remove the V-belt pulley from the crankshaft once again before installing the lower part of the toothed belt guard.
18. Install the belt pulley in place and make sure it is properly seated.
19. Tighten the belt pulley bolts to 20 Nm.
20. Adjust the ignition timing.
Five-cylinder engine
If the timing belt is only removed from the camshaft gear to replace the cylinder head, no special tool is needed.
21. Set the piston of cylinder No. 1 to the TDC position.
22. Remove the V-belt.
23. Remove the toothed belt guard.
24. Loosen the toothed belt tension and remove it.
25. Install counter support 2084 on the crankshaft pulley (with vibration damper) and unscrew the central bolt using extension 2079.
26. Remove the pulley, gear and toothed belt.
27. Mark the direction of rotation of the toothed belt to install it correctly. Always fit the old toothed belt in the correct direction of rotation.
28. Lay a gear belt on the removed gear wheel of a cranked shaft.
29. Install the toothed belt gear with the belt on the crankshaft. Make sure the toothed belt is not pinched anywhere.
30. Install counter support 2084 on the crankshaft pulley (with vibration damper) and tighten the central bolt with extension 2079 to 350 Nm.
31. Make sure that the camshaft and crankshaft are at TDC. If not, rotate the camshaft until the notch mark on the back of the timing belt gear aligns with the top edge of the cylinder head cover. This position can be observed through the viewing hole (see arrow in illustration).
32. Set the crankshaft position mark at TDC, located on the flywheel, opposite the mark in the viewing window on the crankcase. You can also use the TDC reference marks on the V-belt pulley on the crankshaft. The numbers 1 and 2 mark the reference marks with the toothed belt guard installed, the numbers 3 and 4 indicate TDC with the guard removed (see illustrations).
33. Place a toothed belt on the gears of the camshaft and water pump, as well as on the tension roller. Do not change the position of the camshaft and crankshaft.
34. Tighten the toothed belt.
35. Perform two full revolutions of the engine and check the adjustment.
36. Check up position of the distributor of ignition, having fulfilled all actions specified for the four-cylinder engine.
37. Adjust the ignition timing.
Six-cylinder engine
Special tools are required to replace the toothed belt.
38. Remove the ribbed belt together with the tension mechanism.
39. Remove the toothed belt guards on both sides.
40. Set the piston of cylinder No. 1 to the TDC position. The reference marks on the belt pulley and the toothed belt guard must match, and the larger holes on the stop plates of the gears of both camshafts will not face the center of the engine.
41. Remove the ignition timing sensor from the cylinder block, and instead screw in a special tool 3242, called the crankshaft stop. This tool, when screwed in, must go into the corresponding hole on the crankshaft. Tighten the fixture without much force (see illustration).
42. Remove the ribbed belt pulley and the lower part of the toothed belt guard from the crankshaft.
43. Designate a direction of rotation of a gear belt for the subsequent installation. Do not change the direction of rotation of the toothed belt during its subsequent installation.
44. Attach special tool 3243 to the distributor wadding stop plates. This device is called the camshaft stop when it is installed at TDC (see illustration).
45. Loosen the timing belt gear bolts on the camshafts by unscrewing them about three turns.
46. Remove the camshaft stop 3243.
47. Remove the toothed belt gears from the cone of both camshafts. Use a cam puller for this.
48. Insert the cams into the gear holes and rest them against the gear hub. In this case, the pinion bolt remains loosened by about three turns (see illustration).
From this moment, adjustment work is carried out. If the toothed belt is to be replaced, this must be done now.
49. Apply a toothed belt.
50. Attach special tool 3243 to the camshaft locking plates and make sure the tool is installed correctly. The toothed belt gears on the cones of both camshafts must be seated so that they can be turned, but the gears must not be allowed to swing from side to side. The mounting bolt must be tightened by hand.
51. Tighten the toothed belt.
52. Tighten the toothed belt gear bolts on the camshafts with a torque of 70 Nm.
53. Remove the special tools.
54. Reinstall all previously removed parts.
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