A DAYCO brand Tensioner Pulley, timing belt is a part of the timing belt drive, which serves to bypass the belt in a certain place or several places and is a freely rotating pulley of small diameter.

The composition of the roller is small: it is the roller mount, the internal rolling bearing with a protective oil seal, and the working body of the roller itself, which is in contact with the belt.

1. VISA
2. BX (XB-_)
3. BX Break (XB-_)
4. C25 Bus (280_, 290_)
5. C15 Van (VD_)
6. ZX (N2)
7. 205 II (20A/C)
8. 205 Mk II (20A/C)
9. 205 I (741A/C)
10. 205 � (741A/C)
11. 305 II (581M)
12. 305 Mk II (581M)
13. 305 II Break (581E)
14. 305 Mk II Break (581E)
15. 309 I (10C, 10A)
16. 309 � (10C, 10A)
17. 309 II (3C, 3A)
18. 309 Mk II (3C, 3A)
19. 405 I (15B)
20. 405 I Saloon (15B)
21. See more in applications

The principles of the timing belt tensioner work

Excessive tension leads to intensive wear of the timing parts - pulley bearings (water pump, generator, tensioner, etc.), the belt itself, and others. In addition, a tight belt stretches faster and shortens its service life. Too little preload is fraught with more serious problems - slipping of the belt along the toothed pulleys of the camshafts, which leads to a violation of the valve timing and deterioration of the entire engine.

Therefore, a tensioning device is introduced into the timing drive in the form of rollers of one design or another, which, during engine operation, maintain an optimal belt tension.