How Long Should a Car Alternator Last?

The basic function of the alternator is to recharge the battery starter. It should last about 100,000 miles or so. But several factors will determine how long it lasts on a particular vehicle.

Influencing Factors

One factor is the amount of charging required by the vehicle. Some demand a full charge while others don’t. The battery itself is important. If it’s corroded, it’ll need constant recharging. The quality of the alternator is also a crucial factor. Usually the cheap ones don’t last very long.

The usage of high powered electronics must be considered too. The factory stereo won’t require as much power. Keep in mind that the function of the alternator involves powering the other electronics.

If your stereo is high powered, it’ll wear the device out.
A new car alternator should last a minimum of two years. Well maintained it can last up to 8 or 9 years. As stated, the miles you put in is another factor.

Other Functions

The alternator provides power for the electrical components. These include the heater, the wipers and the lighting. It allocates this power as the engine is going. What the device does is produce an alternating current (AC).

Using the rectifier, this is converted into direct current (DC). The alternator is sometimes referred to as rotating electrics. The term is also applied to dynamos.

How the Device is Driven

Usually it is belt driven and linked to the crankshaft pulley. In some vehicles it’s gear / shaft driven. It is usually in the engine bay and next to the engine block. Oftentimes it’s impossible to see. You’ll need to remove some components on top of it.

The numerous functions of the alternator mean it does a lot of work. There are other reasons it might break down. Besides the reasons mentioned earlier, the environment also plays a part. The driving cycle and climate are also factors. If the engine oil leaks, it can lead to a breakdown.

Adding More Components

If you add more components, you might need to replace the alternator. Vehicle manufacturers provide info on the alternator capacity. Adding more equipment requires an alternator with more amps. Depending on your vehicle, you can add another alternator or other battery charger.

Checking for Defects

Knowing the functions of the alternator is just part of the maintenance. Being aware of how to spot defects is the other vital component. The most obvious sign is the flashing battery warning light. Usually this is followed by loss of power. The vehicle won’t be able to start.

If this happens, check the engine. Ensure the drive belt is tensioned properly. Look for any oil or coolant leaks. Double check the connections. These need to be in place.

The heat shields must also be secured. Another method is to use a voltmeter. Run the engine at 2000 rpm. If the alternator is working the battery voltage will go up.

The many functions of the alternator make it a vital component. Properly maintained, it can last for many years without needing repair.