If you’re not sure what a serpentine belt is or why it’s so important, you’re not alone. Many drivers aren’t aware of the role this essential component plays in their engine. Here’s what you should know about serpentine belts, including what they do, maintenance tips, and signs your serpentine belt may need to be replaced.
What is a Serpentine Belt?
The serpentine belt (also known as the fan belt or accessory belt) is a long rubber belt that runs along your car’s engine. Its primary purpose is to power critical components like the alternator, power steering pump, air conditioning system, and in some vehicles, the water pump. The serpentine belt does this by utilizing pulleys and a belt tensioner to transfer power from the engine crankshaft to the various components.
As the crankshaft rotates, it drives the serpentine belt, which in turn rotates other pulleys to power the accessories. Additionally, the idler pulley plays a crucial role in maintaining proper belt tension by creating a sufficient wrap angle, which prevents slippage on the other pulleys. The belt tensioner, also known as the automatic tensioner, ensures optimal tension for the serpentine belt’s performance.
It’s important to note that the serpentine belt should not be confused with the timing belt. The serpentine belt is an external drive belt responsible for powering accessories, while the timing belt is located inside the engine and synchronizes the camshaft and crankshaft.
Serpentine Belt Maintenance
Regular maintenance is crucial for the longevity of your serpentine belt. It’s recommended to have it inspected periodically to ensure the belt is in good condition and isn’t showing signs of wear or damage. Your owner’s manual will have specific recommendations on inspection intervals for your model.
Most experts and manufacturers recommend replacing the serpentine belt around 90,000 miles, regardless of its condition. Taking a proactive approach reduces the chance of a belt failure, which can be dangerous if it happens while driving and can potentially cause severe engine damage. Again, check your owner’s manual for specific replacement recommendations for your vehicle, or ask your service advisor.
If the serpentine belt breaks while you’re driving, several critical systems in your car may be affected, including:
- Power steering
- Water pump
- Air conditioning
Your engine’s computer may also put your vehicle into “limp mode” to protect your engine from damage.
Can You Drive Your Car With a Broken Serpentine Belt?
Although it might be tempting to drive with a broken serpentine belt, especially if your vehicle starts, it’s always best to have the belt replaced as soon as possible. Knowingly driving with a broken or damaged belt poses unnecessary risks to your vehicle and your personal safety. In addition, vital accessories, like the alternator, won’t work—which means the battery won’t recharge. You may be able to drive for 20 to 90 minutes, but you risk being stranded with a dead battery. If it drives the water pump, serious engine damage will occur quickly.
Signs of a Worn or Bad Serpentine Belt
Serpentine belt issues commonly are usually due to one (or a combination) of the following factors:
- Prolonged exposure to heat and friction
- A faulty belt tensioner
- Pulley misalignment
- Defective bearings in the tensioner, idler pulley, or accessories driven by the serpentine belt
If the serpentine belt is misaligned, this can also cause it to experience uneven wear and increase the risk of it failing prematurely. In cases where the tensioner or pulleys are worn or damaged, the serpentine belt may be too loose, which can potentially cause it to be dislodged instead of breaking. Insufficient tension can also impact how the accessories function, such as the power steering pump or alternator.
Recognizing the signs of a worn serpentine belt is important because it allows you to address the issue before it leads to a complete belt failure and potential damage to your vehicle’s components. If you notice any of the following signs, schedule an inspection as soon as possible:
- Squeaking, squealing, or chirping sounds from under the hood
- The check engine light or battery light is on
- Your air conditioning or power steering is malfunctioning
- High engine temperature or overheating
- A burnt rubber odor
If you feel comfortable, you can also perform visual inspections of your serpentine belt at home while the engine is off. Locate the engine, and you’ll see a long belt snaking through various gears along the side. Look for cracks, splits, frays, glazing on the sides, or separating layers. If you see any oil or coolant saturation on the belt, that’s also a clear sign that it should be replaced.
For All Your Maintenance Needs, Turn to Accurate Automotive Attention
Whether you need an inspection or a serpentine belt replacement, Accurate Automotive Attention has you covered! As Yuma’s only AAA-Approved Auto Repair and service company, we’ve been providing high-quality auto care since 1969. With a commitment to friendly and reliable service, we’ve been named Yuma’s Best Auto Repair Shop for 20 years running. Our ASE-certified technicians service a wide range of makes and models, including domestic, Asian, and European vehicles. Contact us today or request an appointment online.
Want more great advice on saving money on car repairs? Order Russell McCloud’s book Knowledge is Power by clicking here.