5 SYMPTOMS OF BAD ALTERNATOR BEARINGS -

This article will show you some of the most common and obvious symptoms of bad alternator bearings.

The alternator is a device that provides your car with electric power and recharges the battery while the engine is running.

One of the crucial parts of the alternator is the bearings. They enable the rotor and pulley of the alternator to spin freely and with minimal friction.

When the two bearings are faulty, mostly due to material fatigue and lack of lubrication, the alternator eventually stops working, and you’re left without electric power, meaning the car is undrivable.

Hopefully, this article will show you how to spot the symptoms of bad alternator bearings on time and help you solve the problem.

Besides this website, you can also watch videos on our YouTube channel, where we have many car-related videos that may help with maintenance, driving, etc.

SYMPTOMS OF BAD ALTERNATOR BEARINGS

1. THUMPING AND GRINDING SOUND FROM THE ENGINE BAY

The first symptom of a bad alternator bearing you’ll notice is the characteristic sound.

First, it will be a barely noticeable thumping sound, which over time gets louder and turns into a grinding and in the final phase of the problem, a crunching sound.

2. THE SERPENTINE BELT SCREACHES AND SQUEALS

Bad alternator bearings cause resistance in the rotation of the pulley and rotor.

This means that the serpentine belt has much more load on it than usual.

The load causes the belt to slip or even start to fray over time, which leads to the serpentine belt making first a chirping, then squealing, and finally a loud screeching sound.

For more information about serpentine belt problems, click here.

3. THE BATTERY WARNING LIGHT APPEARS

You might also get a battery warning light appear on the dashboard.

When the bearings are bad, they might get some play. This play throws the rotor off balance and causes it to scrape the stator and other inner parts of the alternator.

If these inner parts are damaged, the alternator will partially or completely stop producing electricity and recharging the battery.

Click here to get more information about the most common alternator problems.

4. THE SERPENTINE BELT SNAPS

Now we come to the more dramatic symptoms of bad alternator bearings.

One of which is that the serpentine belt suddenly snaps.

We’ve mentioned that bad bearings will put a lot of load on the belt. Because of this, it gets damaged and may suddenly snap, usually while driving.

You’ll easily notice these symptoms when the belt snaps.

The battery warning light will instantly appear. At the same time, other systems may stop working, like the power steering or the AC, for instance, since they are also driven by the serpentine belt.

5. THE ALTERNTOR PULLEY AND ROTOR GET STUCK

Finally, when the bearings completely collapse and the inner parts of the bearing are crushed, the rotor and pulley will get stuck and stop spinning.

First, you’ll hear a loud screeching sound from the serpentine belt, then it may snap, and at the same time, you’ll see the battery warning light appear on the dashboard.

If you were to take off the serpentine belt and try to rotate the pulley, it would most likely be completely stuck or have little play.

This happens, in most cases, if the bearing problem is disregarded and the car is driven for a longer period of time with the grinding noise previously appearing.

CONCLUSION

The best time to inspect and solve a problem with bad alternator bearings is when you hear the distinctive thumping sound while the engine is running.

Besides this, the chirping from the serpentine belt is also an early warning.

The last call is when you hear the grinding. When you hear the grinding, it’s best not to drive the car.

This will help avoid causing further damage to the alternator or, even worse, the car’s electric and electronic systems.

To diagnose a problem with the alternator bearings, if you know how and you can reach it, take off the serpentine belt. Then spin all the pulleys it drives.

The pulley from which you hear a whistling or grinding sound; that’s where the problem is.