2009 Mercedes C300 Belt Diagram (2024)

FAQs

Where is the serpentine belt diagram? ›

Some vehicles have the serpentine belt diagram located on a decal somewhere in the engine compartment. But if your car does not have a decal, you can easily look up the diagram in a repair manual or repair database. Another option is to take a photo of the old belt before removal.

Labor costs are estimated between $94 and $118 while parts are priced between $29 and $42. This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed. For a more accurate estimate based on your location, use our Fair Price Estimator below.

Where can I find a belt routing diagram for my engine? A: Commonly a belt routing diagram sticker is on the underside of the hood or in the engine compartment.

Serpentine belts usually last about 50,000 miles or five years, or in some cases, even up to 100,000 miles. Your belt should be inspected at 50,000 miles, as this is often when you start to see the belt material breaking down.

Serpentine belt replacement is easy because today's automatic drive belt tensioners eliminate the need to loosen bolts or pry components into position for retensioning. Just rotate the tensioner, remove the old belt and install a new one.

Plus, replacement is relatively easy, and if you're wondering how long does serpentine belt service take, it's less than an hour for most vehicles.

A timing belt has horizontal “teeth” designed to fit the cogwheels of the crankshaft and camshaft. A serpentine belt has V-shaped grooves that run vertically along the belt. Drivers often need to replace these belts around the same time.

A serpentine drive belt can make all kinds of odd noises. It can squeak, squeal, chirp and clunk, imitating a bad engine-driven accessory or engine bearing. These noises can fool even the most experienced mechanic and lead to an expensive misdiagnosis.

You can find the correct size of serpentine belt for your car in the owner's manual or by using an online belt sizing tool. If you are unsure about the size of the serpentine belt you need, it is best to consult a mechanic or an auto parts store.

How do I find my serpentine belt number? ›

This industry standard number, frequently denoted as the “PK” number, is printed next to the manufacturer's part number on almost every serpentine belt produced, and can be seen in the examples below. WHAT IS A “PK” NUMBER? A “PK” number is a worldwide standard metric belt measurement printed on most serpentine belts.

The serpentine replacement interval is about every 60,000 – 100,000 miles. Because of their rubber material, serpentine belts will crack, peel, and wear down over time.

Bad Serpentine Belts Cause Vehicle Performance Issues

If your serpentine belt is failing, you may notice performance issues with your vehicle. The vehicle may frequently overheat. Your air conditioning or power steering may fail to work or not work properly.

60,000 to 100,000 miles is typically the most you can get out of a belt, while an alternator may last 150,000 or more miles without complaint. If you've never replaced your serpentine belt, you should definitely do so when servicing the alternator.

Whether you go to the mechanic or do it yourself, replacing a serpentine belt costs $58 to $126. The price of a serpentine belt starts at around $25 and goes up to $75 at most. It typically takes about an hour to replace the serpentine belt, and if you know some car repair basics, you could change the belt yourself.

Depending on the engine in your vehicle, the serpentine belt may be located at the front of the engine bay, or it may be along one side. There may be engine covers in the way, so be prepared to remove them if need be.

The serpentine belt, driven by the crankshaft pulley, is connected to the engine. From there, it wraps around multiple other pulleys that power different components in the engine, such as the alternator, air conditioning compressor, power steering pump, and water pump.

What Does a Serpentine Belt Do? As we mentioned early, a serpentine belt delivers power to your alternator, power steering pump, and air conditioning compressor. In some cases, it also supplies power to your water pump. It's a long, winding rubber band of sorts that is attached to your crank pulley.