Causes for belt failure.
There are several reasons why a timing belt can break. One of them is wear; a belt that is neglected to be replaced will weaken to the stage where it no longer has the strength to fulfil the demands of the load. This is what we could call breaking point. Other common causes are bearing failures of idler and tensioner pulleys. The seizure of a pulley or any of the ancillaries driven by belt can lead to sudden belt breakage.