Skip the auto shop - Our mechanics make house calls

Q: How Do Drive and Serpentine Belts Work?

asked by on

How do drive and serpentine belts work?

A: Accessory drive belts are used to transfer ...

Accessory drive belts are used to transfer rotational motion from the crankshaft to the other accessories on the engine. The driven accessories include the generator, power steering pump, air conditioning compressor, secondary air pump, and the water pump. There are two types of accessory drive belts: V-belts and serpentine belts.

V-belts were used all the way up to the 1990s when they were replaced by serpentine belts. V-belts are shaped like a "V", which is how they got their name. These belts rotate on two or three pulleys to operate their respective accessories. Many older vehicles used multiple V-belts to operate all of the engine accessories. All of the V-belt pulleys rotated in the same direction.

Serpentine belts are so named because they follow a back and forth direction similar to the movement of serpents, or snakes. This is made possible by the fact that serpentine belt pulleys can rotate in either direction. As a result, there is usually only a single serpentine belt to drive all of the accessories on an engine. Serpentine belts use both the ribbed side of the belt and the smooth backside of the belt to operate the pulleys.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Is it just my power steering belt that needs to be fixed, or is it a bigger issue?

When a drive belt breaks, it is necessary to determine the cause. It is not uncommon for a belt to wear out due to age, but sometimes the belt will fail due to another issue. You will need to inspect...

Q: Belt came off

The most common cause of the belt coming off is the belt tensioner or idle pulley. They should be inspected before a new belt is installed. I recommend you seek a mechanic like the certified ones from YourMechanic to come...

Q: Temperature goes into the red zone during slow driving or idling

Hi there. If this occurred right after the work was performed then it is possible that there is air still stuck in the cooling system, but from what you are explaining with the AC, it sounds more like a cooling...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...