Despite doing so much, most of us forget the serpentine belt even exists — let alone that its tension matters. But it does. A lot. Too tight and it'll grind bearings to dust. Too loose and you're ...

Over-tensioning shortens not only the life of V-belts but also that of the sheaves, electric motor, and driven equipment bearings. In extreme cases, it can even bend or break a motor shaft.

The tensioner's bent double-arm design uses two chain wheels or a combination of belt pulleys/flat rollers to compensate for slack in three different areas when a belt or chain is elongated due to ...