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. MX-5 I (NA)
2. MX-5 � (NA)
3. MX-5 / ROADSTER I (NA)
4. MX-5 / MIATA I (NA)
5. MIATA I (NA)
6. 323 S V (BA)
7. 323 PROTEGE V Saloon (BA)
8. PROTEGE V (BA)
9. 323 S Mk V (BA)
10. FAMILIA V (BA)
11. 323 PROTEGE V (BA)
12. ETUDE V (BA)
13. 323 C V (BA)
14. 323 ASTINA V (BA)
15. 323 C Mk V (BA)
16. 323 F V (BA)
17. 323 F Mk V (BA)
18. FAMILIA / LANTIS V (BA)
19. LANTIS V (BA)
20. XEDOS 6 (CA)
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.