Q: Serpentine Belt Keeps Breaking

The serpentine belt is driven by the crankshaft pulley and, in turn, that belt drives a variety of pulleys and accessories, such as the power steering pump, alternator, a/c compressor and so forth. The belt rides along one or more idler pulleys and a "tensioner" as well. All of these devices (the pulleys, the accessories) are referred to as "rotating elements" and, as such, each relies on grease filled ball bearings to roll smoothly with resistance. Eventually, though, the grease gets cooked by engine heat and the balls in the bearings can get worn as well. When that happens the pulleys (or the accessories) start to turn very roughly and can even stop turning or seize. At that point, the belt can break. Basically, all of the "rotating elements" that the serpentine belt rides on have to be carefully inspected for free motion. Any that are sticking or make noise have to be replaced prior to trying a new belt. Inasmuch as all the rotating elements will have to be inspected the best thing to do is schedule an inspection/replacement and the responding certified mechanic will simply carefully go over what you got and let you know of the cost to repair. The cost will depend on how many of the pulleys will have to be replaced. An additional cause of belt breakage is if one or more of the pulleys is not in a single "plane" and, of course, the mechanic will check for that problem as well.