The camshaft drive belt is tensioned by an automatic tensioner and cannot be adjusted.
The tension of the balance shaft drive belt "B" is subject to adjustment on the vehicle (see below).
To decide whether to replace the belt, it is necessary to inspect it for defects.
Possible defects of timing belts
Hard, non-elastic, hardened rubber on the back of the belt. No mark is left on the surface when pressed with a fingernail.
Cracks at the base of the teeth and cord delamination.
Cracks on the back of the belt.
Tears or cuts on the side of the belt.
Heavy side wear and rounded edge.
Severe wear or missing teeth.
Adjusting the tension of the toothed belt "B" of the balance shaft drive
1. Remove the top protective cover.
2. Turn the crankshaft clockwise and align the timing marks of the pulleys as shown in the figure.
Caution: Do not turn the crankshaft counterclockwise as this will result in incorrect belt tension results.
3. Remove the protective caps (1) from the technological holes of the bottom cover.
4. Loosen the tensioner mounting screws (flange screw - 1 turn, and Allen screw - 1-2 turns). This will cause the tensioner to move and tighten the belt.
After this, tighten the Allen screw first, and then the flange screw.
Tightening torques:
- allen screw - 20±4 Nm;
- flange screw - 23±3 Nm.
5. Replace the protective caps and the upper protective cover (see Fig. M21.019).