How do you know if your alternator pulley is bad?

If you ever hear growling or whining noises coming from under the hood, you could have alternator problems, which should be checked out by a professional ASAP. This growling or whining sound happens when the belt that turns the alternator's pulley becomes misaligned or rubs against the side of the pulley.

What happens if the alternator pulley is bad?

If the clutch or spring inside the pulley has failed, the pulley may fail to drive the alternator, or it may create vibrations and noise.

Can I drive with a bad alternator pulley?

So, how long can you drive with a bad idler pulley? The safety recommendation is not to drive the car at all and take it to a mechanic immediately. You should be concerned if the vehicle makes squeaking or rattling noises. The car can still run for months or break after a few days.

What causes alternator pulley to go bad?

Pulleys do go bad because the grease in the pulley bearing dries out, the ball bearings and bearing races get pitted and then the pulley becomes noisy. Sometimes, the pulley will actually seize. However, it will be EASILY evident if a pulley bearing is bad. So, all you need to do is have them PROVE the failure to you.

How much does it cost to replace an alternator pulley?

Labor costs are between 64 and $81 while parts are between $79 and $83. Taxes and fees are not included in the estimate.

How to: Test

How do you fix a pulley sound on a alternator?

Why is my alternator pulley squealing?

Worn Bearings

An alternator's bearings can become worn and create noises, including a squeal. An alternator with worn bearings will likely produce an insufficient charge to operate the engine and charge the battery. To test for worn bearings, remove the belt and turn the pulley by hand.

Can a bad idler pulley cause alternator problems?

Alternators are DRIVEN by the serpentine belt. All that happens when the belt disappears or pulleys seize is the alternator stops turning; there is NO possibility of damage to the alternator.

How do you test an alternator pulley?

Rev up the engine to approximately 2000-2500 revolutions per minute (rpm). Then shut it off and listen for a buzzing sound coming from the alternator. If you hear a short buzzing sound (1 to 5 seconds), the pulley's bearing may have worn out and the overrunning alternator pulley may require replacement.

Can I replace just the pulley on an alternator?

In many cases it is possible to remove and install the overrunning alternator pulley while the alternator is still on the engine. The plastic protective cap cannot be re-used after it has been removed from the pulley. A replacement cap is supplied with the new part.

Can you buy just the alternator pulley?

It is also recommended that you replace the alternator pulley anytime you install a new alternator. You'll have no problem finding a pulley at AutoZone since we carry the best alternator pulleys for cars and trucks. Check out our large inventory of pulleys and get your vehicle running smoothly in no time.

How much does it cost to replace a pulley?

Idler Pulley Replacement Cost

The cost to replace the idler pulley of your driver belt will usually be somewhere between $80 and $200. The cost for the new part should only be anywhere from $40 to $90, while the cost of the labor will be anywhere from $40 to $110.

How long does it take to replace a pulley?

If you are doing the job at home, give yourself about four hours to change all the parts. You will need the following tools and parts: Replacement idler pulley.

How many pulleys does a car have?

Modern vehicles usually have more than one belt and pulley. However, older vehicles have perhaps one. Modern manufacturers would rather replace your belts only once every 50 miles, or the belt will break, which will result in your engine going out of control.

Is an alternator worth replacing?

It's usually a better idea to replace the alternator entirely if it is malfunctioning. While new ones can be spendy, they are usually a better choice than remanufactured or rebuilt options. Those probably won't last as long as a new one since the mechanical parts have miles on them already.

Can a bad pulley cause loss of power?

Technically speaking, yes, an idler pulley will result in a slight power loss.

What is the alternator pulley?

The alternator pulley allows the V-shape or serpentine belt to spin the alternator and is driven by the engine's accessory drive system. Commonly made from stamped steel or cast aluminum, alternator pulleys are available in two types. One type is grooved for use with a V-type fan belt.

How do I know if my tensioner is bad?

One of the most common symptom of a bad or failing drive belt tensioner is noise from the belts or tensioner. If the tensioner is loose the belts may squeak or squeal, especially when the engine is first started.

What happens if idler pulley breaks?

Damaged bearing or pulley

A broken or seized pulley can quickly lead to a torn belt, or in less serious cases, the belt falling off of the engine. An engine without a belt can quickly run into issues such as overheating and stalling, as it's the drive belt that allows the engine accessories to function.