Table of contents: Petrol engines ↓ Diesel engines ↓
Petrol engines
The toothed belt tension can only be adjusted on a cold engine. In workshops, the toothed belt tension is adjusted by tightening the tension roller. For this, use the Matra V 159 impact wrench.
1. Remove the timing belt cover.
Four-cylinder engines
2. Loosen the timing belt tension roller clamp bolt.
3. To tighten the toothed belt, rotate the tension roller counterclockwise with a wrench. Tighten the tension roller clamp bolt to a torque of 20 Nm.
When performing this operation without using an impact wrench, proceed as follows:
4. Insert a strong screwdriver into one of the holes in the camshaft gear and turn the gear slightly to the left to relieve the tension on the timing belt.
5. Loosen the timing belt tension roller clamp bolt.
6. Insert a small screwdriver into the slot of the eccentric screw and turn the screw in the direction shown by the arrow in the illustration until the timing belt tension is within the desired values. When performing this operation, the camshaft gear must be held from turning.
7. Tighten the tension roller clamp bolt and check the timing belt tension again.
Five-cylinder engine
8. Loosen the timing belt tensioner mounting bolts.
9. Rotate the tensioner hexagon with a torque wrench clockwise to 25 Nm to tighten the timing belt (see illustration).
10. Tighten the tensioner mounting bolts, holding the tensioner in this position, to a torque of 10 Nm.
Six-cylinder engine
11. Remove the V-belt and the V-belt tensioner mechanism.
12. Loosen the tension roller clamping bolt with an 8 mm Allen key (see illustration).
13. Rotate the tension roller with an 8 mm socket wrench to the right until the tension of the toothed pet. reaches the norm.
14. Tighten the tension roller clamping bolt with a second socket wrench to a torque of 45 Nm, holding the tension roller in this position.
Diesel engines
To adjust the tension of the toothed belt, workshops use an impact wrench, such as the Matra V 159, to rotate the adjusting eccentric. Such an impact wrench is available for sale.
15. Remove the upper part of the timing belt guard.
TD Engines
16. Measure the timing belt tension.
17. Loosen the tension roller clamp nut.
18. Insert the impact wrench into the holes of the tension roller eccentric.
19. Tighten the toothed belt by turning the eccentric.
20. Tighten the tension roller clamp nut.
21. Measure the tension of the toothed belt. To do this, press the belt with your hand at the location where the measuring device is installed so that the belt deflection is at the measurement location.
TDI engines
22. Loosen the tension roller clamp nut.
23. Insert the impact wrench into the holes of the tension roller eccentric.
24. Rotate the eccentric with the impact wrench to the right until the notch and the shoulder on the tension roller are opposite each other (see illustration 11.9).
25. Tighten the tension roller clamp nut.
26. Check the valve timing adjustment and the start of the injection pump. This requirement applies to both engine types.