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. CX II
2. CX I Break (MA)
3. CX � Break (MA)
4. CX II Break
5. CX Mk II Break
6. C25 Bus (280_, 290_)
7. J5 Bus (280P)
8. J5 Platform/Chassis (280L)
9. J5 Bus (290P)
10. J5 Platform/Chassis (290L)
11. J5 Van (290L)
12. DUCATO Van (280_)
13. CX I (MA)
14. CX � (MA)
15. C25 Van (280_, 290_)
16. C25 Platform/Chassis (280_, 290_)
17. J5 Van (280L)
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.