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. FIESTA IV (JA_, JB_)
2. FIESTA Mk IV (JA_, JB_)
3. 121 III (JASM, JBSM)
4. SOHO III (JASM, JBSM)
5. FIESTA Van (J5_, J3_)
6. COURIER Van (J5_, J3_)
7. PUMA (EC_)
8. FOCUS (DAW, DBW)
9. FOCUS Saloon (DFW)
10. FOCUS Turnier (DNW)
11. FOCUS Clipper (DNW)
12. FIESTA V (JH_, JD_)
13. IKON V (JH_, JD_)
14. FUSION (JU_)
15. 2 (DY)
16. DEMIO (DY)
17. FOCUS C-MAX (DM2)
18. FOCUS II (DA_, HCP, DP)
19. FOCUS II Turnier (DA_, FFS, DS)
20. FOCUS II Station Wagon (DA_, FFS, DS)
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.