A SNR 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. VECTRA A (J89)
2. VECTRA A Hatchback (J89)
3. ASTRA F Hatchback (T92)
4. ASTRA F (T92)
5. OPTIMA F (T92)
6. ASTRA F Estate (T92)
7. COMBO Box Body/MPV (71_)
8. ASTRA Mk III (F) Hatchback (T92)
9. ASTRA Mk III (F) Estate (T92)
10. CAVALIER Mk III Saloon (J89)
11. CORSA B (S93)
12. VITA B (S93)
13. CORSA Mk I (B) (S93)
14. COMBO Mk I (B) (S93)
15. CAVALIER Mk III Hatchback (J89)
16. ASTRA Mk III (F) Saloon (T92)
17. CORSAVAN Mk I (B) Hatchback Van (S93)
18. CORSA B Hatchback Van (S93)
19. 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.