A OPTIMAL 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. STARLET (_P7_)
2. STARLET (_P8_)
3. COROLLA Liftback (_E8_)
4. COROLLA (_E8_)
5. COROLLA Saloon (_E8_)
6. COROLLA Liftback (_E9_)
7. COROLLA (_E9_)
8. COROLLA Saloon (_E9_)
9. COROLLA Compact (_E9_)
10. COROLLA Station Wagon (_E9_)
11. COROLLA FX Compact (E8B)
12. COROLLA Compact (_E10_)
13. COROLLA SECCA Compact (_E10_, AE102)
14. COROLLA Liftback (_E10_)
15. COROLLA (_E10_)
16. COROLLA Saloon (_E10_)
17. COROLLA Estate (_E10_)
18. 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.