Will An Alternator Work Spinning Backward?

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The alternator is a very important component of a car’s engine makeup and one must be sure that every precautionary measure is in place to avoid its damage; but should you be concerned if your alternator begins to spin backward? Will an alternator work spinning backward?

Yes, your alternator will work perfectly if it spins in the opposite direction. The rectifier bridge in the engine directs the current in the right direction depending on the cycle thereby changing it to direct current (DC) in the process. Regardless of which way the alternator is spinning, it will still produce alternating current (AC), so you need not worry.

Now that you know an alternator spinning in reverse motion cannot damage it, it’s equally important to note what can damage an alternator:

Table Of Contents

What can damage an alternator?

Before I go into the finer details, you should know that there are two types of alternator damage which are; electrical and mechanical faults.

Electrical faults

The electrical faults in an alternator can range from defects in the diode bridge and winding ruptures which can affect the smooth workings of an alternator in your vehicle.

Mechanical faults

The mechanical faults alternators are known to mostly consist of failures in the bearings and fasteners which can have a damaging effect on an alternator if it’s not noticed quickly.

Having known that, below are the common reasons an alternator can go bad.

The alternator in question is too old

This should be one of the foremost things that come to mind when you feel your alternator is bad, especially if you have used it for a while. The regular life expectancy of a good alternator ought to be somewhere in the range of 5 and 8 years. In case it has been that long and you have electrical challenges from time to time, then, it is most likely that your alternator may essentially be bad; and if your car mechanic suggests you get a new one, don’t hesitate. 

In case you feel it’s your battery that is to blame, the common life expectancy of a battery is somewhere in the range of 2 and 5 years. Climates that are typically hot will deplete the battery power faster, so it very well might be 2 years for you in these cases. However, the temperature shouldn’t influence the alternator in any way at all.

Computer malfunction

Modern vehicles are designed with computer installations in them like the ECU. These installations are what oversee essentially every part of the vehicle, including the alternator.

Assuming there were to be an issue or error with the computer being installed, it could prevent the alternator from charging appropriately regardless of whether it’s a pretty good alternator or not.

Chances are there’d be different issues that would emerge from the computer installations as well. The best thing to do in this case would be to visit a car mechanic for proper diagnosis – you would be well-advised not to take matters into your own hands.

Issues with the wiring

There are bunches of wires in the vehicle which convey power to the alternator. Assuming one of these wires were to become harmed or spoilt, then, at that point, it could make the alternator fall flat at its particular work and the battery not get charged.

Assuming you don’t see any of the different issues discussed in this article being available in your vehicle, then, at that point, check the wiring of the alternator since that might be the justification for your alternator not working as it should – you might need the help of an expert for this exercise.

Spoilt fuse

A spoilt or burnt fuse can be another reason why you’re alternator might malfunction and refuse to charge your battery. Fuses can get destroyed during a power surge, and as a result, the alternator might lose its ability to charge a battery.

Before you rush to the repairer’s shop, try doing some troubleshooting on your own – simply pull out the user manual of your vehicle and locate where the fuse of the alternator might be.

After locating the fuse, test to see if the alternator fuse is blown and replace if it is – your alternator should be fine afterward.

Damaged belt

Alternators utilize the mechanical force of a belt and pulley to create the electrical energy for the vehicle. The issue is that the alternator belt and pulleys are not very sturdy, which implies they can break if certain factors come to play such as wear and tear. 

Pulleys will commonly keep going for quite a while before they ultimately get worn out due to how long they have been used.

Some belts are thin and will ultimately begin to break after a while. Assuming that both of these things were to occur, there would be no mechanical energy being produced for the alternator to convert to electrical energy which can become a problem for the alternator itself.

How do I know my alternator is going bad?

There are several indicators you can use to tell if your alternator is going bad, however, I will be pointing out the most common and easiest signs.

Alternator warning lights

One of the first places you are likely to notice issues with your alternator would be the warning sign on your dashboard, but this is mostly available in newer models.

New vehicles made in the last 7-8 years have a devoted alternator cautioning run light to flag an alternator issue. A few vehicles utilize their check engine light or battery light, however, others might show “ALT” or “GEN,” suggesting the alternator or generator needs fixing. 

Battery-check light interfaces with the computer frameworks inside your vehicle to screen the alternator’s maximum output. Assuming the alternator maximum output transcends or falls below the expected limit, you’ll begin encountering issues with your electrical framework, and the light will turn on. 

A sound alternator ought to have a voltage result of somewhere in the range of 13V and 14.5V. As you utilize specific electrical parts, similar to the fog light, windshield wipers, and the radio, your alternator needs to work more enthusiastically to keep up with the important voltage. 

Assuming your alternator is acting up, the voltage will either be above or beneath the set level, thereby activating the caution light.

Overly dim or bright lights

Since the alternator controls your vehicle’s electrical framework, one of the principal indications of a faltering alternator is electrical disappointments. 

You may see glinting headlights, or the inside lights are diminishing or turning out to be too bright. Your tachometer, speedometer, radio, or dashboard lights may also suddenly stop working. These are indications of an issue with your vehicle’s electrical framework. 

There’s no accuracy to determine which one starts acting up though as it depends on several factors; such as the design of your vehicle and how good your alternator has been performing.

Numerous new cars have a prearranged program where the alternator sends power. Security is usually the watchword here, so while encountering electrical disappointments, your vehicle’s radio will probably go before other items begin to malfunction.(Read Also:Will A Bad Alternator Diode Drain The battery?)

Weird noises

Vehicles make lots of noise, some of which are totally ordinary while others can show a fault. However, a sound associated with a bad alternator is a growling sound as you would have with a dog being agitated. 

Related to the crankshaft, a drive belt or serpentine belt makes the alternator function. Normally, the alternator pulley turns around a few times quicker than the driving rod pulley to deliver the power important at lower speeds.

Assuming the alternator pulley isn’t lined up with the drive belt as it should be, or the alternator orientation is damaging little by little, it by and large makes a growling sound, meaning you might have an alternator issue. 

Avoid leaving a terrible alternator on for such a long time as it can cause severe damage to your car’s engine.

Assuming that this occurs, you’ll presumably begin hearing shaking noises from inside your motor brought about by damaged engine bearings.

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Does it matter which way an alternator spins?

Not at all! Regardless of where you place an alternator in front of your engine, it is bound to rotate the same. 

Can you spin an alternator by hand?

This depends on what you mean. If you mean an unplugged automotive alternator that isn’t plugged and has no belt connecting it to the engine, then you can go right ahead.

Why would an alternator seize?

The seizing of alternators is dependent on several factors such as accumulated debris and the constant climatic change – hot and cold weather. One of such common failures is the bearing failure which can cause the rotor not to spin as it should, thereby causing it to seize.

Can I use a car alternator as a generator?

Yes, you can’ but there are certain things that need to be in place. For starters, you would need a constant source of rotational power – if you can’t get this, then you might as well forget about the entire procedure.

You would need a horsepower rotary drive that can make it turn about 1000-2000 revolutions per minute (RPM)

Will An Alternator Work Spinning Backward – Conclusion

Will an alternator work spinning backward? Since we now know it can, I would employ you not to panic if yours seems to spin backward. Kindly drop your comments and suggestions in the comment section. Cheers…

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