For the belt tensioner, which maintains tension of the belt for the engine auxiliary devices, the section where the pulley bracket is secured by caulking does not have sufficient strength, and that section may break from reaction force of the belt, in which case the pulley bracket could come off from it. If this occurs, the pulley may separate from the belt, causing the water pump and the alternator to stop functioning, and in the worst case, the pulley and the bracket could fall off, which could impede other traffic.