Automotive Maintenance And Detailing


Automotive Maintenance And Detailing

What does car alternator do?.

What does car alternator do?. An alternator is an essential part of a vehicle’s electrical system. Alternator supplies electric current to batteries and in-vehicle electrical equipment such as headlights, horns, ignition coils, electric windows, windshield wipers, and much more.

An alternator is an alternator with a rectifier, which converts it to DC power and supplies it in the car.

All cars have a battery installed, but they are mainly responsible for delivering power to the starter motor to start the engine and provide momentary power to the car’s device while you turn off the engine. Therefore, if you run on battery power for a long time with the engine not running, the battery power will discharge completely. An alternator has a role to play in charging the current, always replenishing the battery.

The alternator installs on the engine and is driven by a serpentine belt. The resulting current runs directly to the battery and various devices. It is a generator with a lot of different amps depending on the car model. Small cars that don’t have a lot of electrical equipment will use a low current alternator, but larger cars may need a higher amp. Modern vehicles such as SUVs may require an alternator with up to 180 amps to be sufficient for the vehicle equipment.

What components does an alternator have?

An alternator is a car device that works like a standard generator. It has the following internal components.

  1. Rotor and stator

The rotor and stator are the main parts of the generator. When the rotor spins from the engine, it rotates through a magnetized stator, creating a magnetic field. This magnetic field will cause an alternating current.


A rectifier consists of a diode that converts and rectifies the direct current. The alternator’s direct current supplies to the battery and vehicle device for use. Before sending it out, it has to go through another necessary device, the voltage regulator.

  1. Voltage regulator

The voltage regulator has the function to regulate the current level sufficiently for use with the equipment in the car. Most cars use a minimum of 12.5 volts, but not more than 14.5 volts. The current that is sufficient to turn the starter motor must not lower than 12.5 Volts and have a high CCA (Cold Cranking Amp) value according to a specification of that battery or the car model. Otherwise, the car will not start.

  1. Ball Bearings

Both front and rear rotor axes are balls bearing for smooth rotor rotation. This bearing is durable in use, but it also has the potential to break.

  1. Pulley

The pulley is installed at the end of the outer rotor axis to allow the belt drive to keep it from turning. This pulley is available in both a normal and a freewheel type pulley. A freewheel pulley is a pulley designed to reduce vibration as it spins. It will be able to free spins forward several more revolutions as you turn off the engine. These pulleys tend to break after prolonged use.

A Voltage Regulator

What are the symptoms of a broken alternator?

  1. Battery warning light

You need to know how the car will react when the alternator breaks down to fix it before breaking down on the road. Most vehicles have a red battery warning light on the dashboard. There are two possible reasons for this icon showing, either the battery or alternator is broke.

Checking the battery is dead or not by jumping start from another car battery. If the battery is good, your engine will resume when the alternator is charging. You will be able to start the car again after driving for 1 or 2 hours and turn off the engine.

It can happen if you forget to switch off the electrical pieces of equipment in your car until the battery has completely discharged.

But you won’t be able to start the car again if the battery is dead because it can’t hold a charge.

If the alternator fails to charge the battery and you do not have enough power to start the car, your engine will stall after removing the jumper wires. That’s because there is no power in the system at all.

  1. Symptoms of flashing car devices

Modern cars use a lot of electrical equipment.   If they are not receiving power from batteries or alternators, they will stop working. Plus, what you can notice is that the headlights will flash as you try to start the vehicle.

  1. The device in the car malfunctions

In cars with electric steering or electric hydraulic pumps, the steering sensation becomes heavy when you turn. The electric tailgate may not work when you try to open or close it. The engine also stalls when you accelerate the engine. That is because the fuel pump, coil, spark plugs are not receiving electricity from the alternator.

  1. Abnormal sound at the alternator

You may hear a grinding sound at the alternator mounting position. Broken bearings will make a grinding sound. The broken rotor bearings cause the pulley to spin more slowly than usual due to friction. The current from the alternator is lower than it should be and will affect the electrical equipment.

Broken belts may also get stuck between the pulleys of the engine belt system. If you find that the alternator belt tear during the run, have the car repaired immediately, as the battery power will soon run out.

Check Engine Light

Replace or repair the alternator

Defective parts are usually built-in rectifiers such as a rectifier, voltage regulator, slip ring, freewheel pulley.

The mechanic can change the broken piece if you choose to repair them. You can save money in your pocket and still be able to use it for a long time. But you need to wait for the repair by a technician.

If you need a car because you drive it to work or send your child to school every day, then you should replace the alternator. It’s a quick and easy method, but you pay a lot for a new alternator. Another option is that you can change it with a rebuilt alternator. An alternator like this is a used, broken one, and a mechanic replaces the internal parts and cleans it to look like new, so the rebuilt alternator is reasonably cheaper than the new one.

The old car alternator can be rebuilt

Alternator service life and maintenance


The alternator is a highly durable automotive lighting device. You can drive 120,000 miles or 200,000 kilometers without worrying about breaking down. But it will eventually be damaged.

However, if you use it recklessly, it can damage your alternator prematurely. Cleaning the engine compartment without covering it with plastic wrap can result in water getting inside and damaging parts.

Slack or excessive tension in the drive belt can damage the rotor axis bearing.

You’ll need to open the bonnet, check the condition of your alternator belt frequently, and be careful with water entering it if you enjoy washing your car yourself and love cleaning the engine compartment.

Choosing the right alternator for your car

In case your alternator is damaged and needs a replacement, it is essential to keep in mind the correct amp size according to the car model. If you choose an alternator with a lower amperage than your car’s specifications, you may experience an inadequate power supply, and some devices may fail.

On the contrary, if you choose an alternator with a higher current than necessary for the car, You will waste a lot of money for a reason. You may opt for a higher-spec amp model if you install additional electrical equipment, such as an audio installation with a high wattage power amplifier, a spotlight booster, or other devices other than standard equipment. Installed at the factory

It is ideal to use an alternator as determined by the vehicle manufacturer as it will not cause any subsequent problems.

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