How Belt Tensioners Work

The drive belt tensioner in your car is a small component that works in conjunction with the serpentine belt to ensure that everything in your engine works as it should. From time to time, the tensioner should be checked to ensure that it’s set correctly. Your mechanic can do this for you as part of your routine maintenance. On occasion, it may have to be replaced.

What does the belt tensioner do?

In your engine compartment, the serpentine belt winds around various components, including your alternator, power steering pump, water pump, air conditioning compressor, and more. The tensioner ensures that the belt delivers enough tension while you’re driving, so that the belt can move the various pulleys that drive the engine components.

The parts

The drive belt tension is made up of four main parts – the base, tensioner arm, spring and pulley. The base holds the other parts, and the spring keeps the belt pulled tight. The pulley is what facilitates movement of the belt. The tensioner arm is found on the bottom of the tensioner, and if you press on it, it will work against the spring, delivering enough slack so that you can adjust or remove the belt.

Adjusting the belt tensioner

Adjusting the drive belt tensioner is not something you should attempt to do yourself – leave this job up to a pro. The serpentine belt is absolutely vital to the function of your vehicle, and if you end up with a belt problem due to an improperly adjusted tensioner, the damage can be catastrophic.


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Recent Drive Belt Tensioner Replacement reviews

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Tinashe

13 years of experience
605 reviews
Tinashe
13 years of experience
Ford F-150 V8-5.0L - Drive Belt Tensioner - Clarkston, Georgia
Very friendly and very knowledgeable. Was on time and even early. He explained what he was doing every step of the way .
Mazda 6 - Drive Belt Tensioner - Decatur, Georgia
Great service! Extremely polite and informative. He is extremely reliable! He came in a day early just because he had a slot open! He showed me exactly was causing the problem in my car and how to properly fix it. I will definitely be keeping him as my mechanic!

Tony

40 years of experience
12 reviews
Tony
40 years of experience
Chrysler Pacifica V6-3.5L - Drive Belt Tensioner - Stockton, California
He was wonderful and went above and beyond he was fast and efficient as well and we want to thank him again for his professional job

Alec

15 years of experience
3 reviews
Alec
15 years of experience
Kia Optima L4-2.4L - Drive Belt Tensioner - Melville, New York
Alec was very knowledgeable and a did fantastic job. Would definitely use his services again in the future.

Luke

17 years of experience
150 reviews
Luke
17 years of experience
Ram 1500 V8-5.7L - Drive Belt Tensioner - Sandy, Texas
Fast, Easy, and Professional. Scheduled Luke again for maintenance and brake pads. Book him up, one of the best!

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