Serpentine Belts Q&A

What's A Serpentine Belt? Why do I have one?
— -Sounds Like Mythology

Berning’s Auto Repair Answer:

Back in the day, each of your engine’s accessories, like the alternator and air conditioner, were powered by separate belts. A vehicle might have 5 or 6 belts. These days, vehicles often have a single belt to run all the accessories. The power steering and power brake pumps are driven by the serpentine belt in many vehicles. In some vehicles, the water pump is driven by the serpentine belt (in others it’s driven by the timing belt). The radiator cooling fan on some vehicles are also driven by the serpentine belt, while others have separate electric motors. It’s called the serpentine belt because it snakes around everything, efficiently connecting the accessories.

A pulley attached to the vehicle engine’s crank provides the power to turn the serpentine belt. The belt may provide the power for the power steering pump, which makes it easier to steer your vehicle. Next comes the alternator which generates electricity to run the vehicle’s electrical system and charge the battery. On to the air conditioning compressor. This helps make cold air to keep you comfortable all summer long, and many vehicles use the air conditioner to defrost the windshield because of the a/c’s ability to pull moisture out of the air.

On some vehicles the water pump or radiator fan or the power brakes are also run by the serpentine belt. Some even have two serpentine belts. No matter how your engine is arranged, you aren’t going far without a serpentine belt.

Finally, there is the belt tensioner. Its job is to apply pressure on the belt to keep it tight. Several years ago, manufacturers started making serpentine belts out of a new material. It’s much more durable, but it’s harder to tell when the belt needs to be replaced. The old style belts would crack and chunks would fall off so you could easily see when you needed a new one. On the new style belts, if the ribs wear too deep, it’s time to replace. Our service techs uses a simple gauge to tell when the belt is worn and you need a serpentine belt replacement. A worn belt stresses your vehicle engine’s expensive accessories and causes them to wear prematurely. Your vehicle manufacturer has a recommended interval for inspecting your belt and we can inspect it for damage or wear.

What are the warning signs that there’s a problem with the serpentine belt or the belt tensioner? You may hear a squealing sound from under the hood when accelerating. A loose belt might give you a slow, slapping sound.

If you suspect a serpentine belt problem, or if it’s just been a while since it was last checked, ask your friendly Berning’s Auto Repair service advisor to have it looked over.

So, change your serpentine belt and belt tensioner as recommended by your friendly Berning’s Auto Repair service advisor to extend the life of your accessories and to prevent future breakdowns.

Comments are closed.