Is your alternator faulty, and do you want to replace it? Don’t worry; this article explains how to replace a faulty alternator.
An alternator is an electrical device that is used to convert the mechanical power of the engine into electrical power in the form of AC (alternating current). It has a rectifier that is used to transform the output AC into DC. The output DC is used to charge the battery of the vehicle.
The primary purpose of the alternator is to charge the vehicle battery. When the battery is properly charged, it is used to run different electrical systems of the vehicle, such as the starter and headlights.
The alternator is usually installed at the engine front and is driven by the engine crankshaft.
How Does an Alternator Work?
The working of the car alternator is very simple and easy to understand. The alternator has two windings, i.e., a rotor and a stator. The rotor rotates inside the winding while the stator remains stationary outside the winding. As the voltage regulator delivers voltage to the rotor winding, it starts rotating in a magnet.
The car engine shaft connects to the pulley via a drive belt. The pulley further connects to the alternator. As the engine shaft rotates, it turns the pulley, which further turns the shaft of the alternator.
When the shaft or rotor of the alternator turns, it produces alternating current (AC). The rectifier further converts AC into DC and transfers resulted DC to the battery. The battery further uses this DC to run the starter power.
Components of an Alternator
The alternator has the following components:
- Regulator
- Rectifier
- Rotor
- Slip Rings
- Slip Ring End Bearing
- Stator
- Drive End Bearing
- Pulley
1) Regulator
A voltage regulator uses to control the current flow from the alternator to the battery. It also handles the charging process of the battery. This part performs a different function according to the nature of the application.
2) Rotor
The rotor is one of the most important parts of the alternator. It contains multiple blades. It rotates and turns the pulleys and driving belt system. The rotor works like a rotating electromagnet.
3) Rectifier
When the engine turns the alternator, it produces alternating current. However, a car battery needs a direct current (DC) to be charged. The rectifier converts the AC into DC and charges the battery.
4) Pulley
It connects to the drive belt system and rotor shaft. When the engine crankshaft rotates, the drive belt takes rotation by the engine and transfers it to the pulley.
The rotation of the pulley plays a big role in generating the electric current, which further uses to charge the battery.
5) Slip Ring End Bearing
These types of bearings are intended to rotate the rotor shaft.
6) Stator Motor
It is an iron ring around which multiple coils are wound. Some portion of the stator acts as the housing of the alternator. It generates an electric current when the magnetic field is generated.
Read More: Working and Parts of Starter
7) Drive End Bearing
The drive end bearing also assists in rotating the rotor shaft.
8) Slip Rings
The slip ring is a method of generating DC (direct current) and powering the rotor.
Read More: Bad Alternator Symptoms and Causes
How to replace an Alternator
The proper working of the alternator is very important to get the best performance by your vehicle. When the alternator goes bad, it creates different problems and reduces the engine power. When you observe that your alternator is bad, you need to replace it as soon as possible. Follow the below given general steps to replace an alternator:
- Park the vehicle: First of all, you need to park your vehicle in a safe and leveled place.
- Remove the negative terminal of the battery: Disconnect the negative terminal of the battery connected to the alternator. If you do not remove the battery terminal, you may get an electric shock while working on the alternator. Open your vehicle hood and find the battery. Disconnect the negative terminal of the battery by using the wrench.
- Locate the alternator: It’s time to search for the alternator. It is usually installed at the front of the engine, near the top. After locating the alternator, properly check the size of the mounting bolts that keep the alternator in its original position.
- Remove the alternator belt: A serpentine or V-belt is used to connect the engine to the alternator. Use a tensioner tool or a wrench to loosen the tension on the belt and remove it from the alternator pulley.
- Disconnect the electrical wires: As we discussed above, the alternator is used to supply electrical power to various vehicles’ electrical accessories by using multiple wires. Remove these wires so that you can easily remove the alternator.
- Remove the bolts: Multiple mounting bolts are used to hold the alternator in its original place. Use a socket wrench or a wrench to remove these bolts.
- Remove the faulty alternator: After removing the mounting bolts, you will be able to remove the alternator. Gently pull the alternator and remove it from the engine compartment.
- Inspect the alternator: Properly inspect the old alternator after removing it. If it is dirty, properly clean it. If it is badly damaged, you will need to replace it with a new one.
- Install the new alternator: Now, install the new alternator in its original place in the engine compartment. Properly tighten it in its position by using the mounting bolts.
- Reconnect the wiring: Again, connect the electrical wires back to their original place. Make sure that wires are properly connected to the new alternator.
- Put the alternator belt: Reinstall the alternator belt back on the pulley and properly secure it to the correct tension.
- Reconnect the negative terminal: Now, reconnect the negative terminal of the battery to the alternator.
- Test the alternator: Turn on the ignition switch and start your engine to check the performance of the new alternator. While the engine is running, check the output voltage of the alternator using a multimeter.
FAQ Section
What is the function of the alternator?
The main function of an alternator is to charge your car battery so that other electrical components in the car can be powered.
How do I know if my alternator is bad?
- Engine misfiring
- Dead battery
- Dim lights
- Whining noise
- Burning rubber or wires smell
- Stalling
- Malfunctioning or slow accessories
- Warning light
Is replacing an alternator a big job?
Replacing the alternator is a simple task that requires just basic tools and minimal mechanical experience. It is comparable in difficulty to changing the oil or replacing a serpentine belt, making it an ideal beginner maintenance task.
Can I drive with a bad alternator?
Although it is technically possible to continue driving with a faulty alternator but it is not recommended, particularly in the new cars that rely heavily on electricity. Since the alternator is a crucial component of the battery’s power system, prompt repair is necessary.
How far can my car go with a bad alternator?
In general, you should seek repair services quickly if you notice a problem with your alternator. You may be able to drive for around 20 to 32 minutes with a fully charged battery, but relying on a faulty alternator can lead to more significant issues in the long run.
Will a bad alternator drain a battery?
Yes, a faulty alternator may drain your car battery, although it is uncommon. This can happen if there is an issue with the alternator’s components or connections.
Why do alternators go bad quickly?
Because alternators contain moving parts that may become dirty and suffer from wear and tear over time, particularly when exposed to extreme temperatures. Bearing failure is one of the most common issues that can cause an alternator to malfunction.
How does a bad alternator sound?
If you notice a grinding noise in your vehicle, this may be a sign of a faulty alternator. The grinding sound often results from a worn-out bearing within the alternator.