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Guide to Replace a Car Alternator

Stephen Rampur
Vehicle charging systems have improved by leaps and bounds over the past few years. But if you own an old car which is in regular use, you might end up seeing the light on your dashboard indicating that the alternator has failed. Here's a guide to replace a car's alternator.
The charging system totally depends on the car's alternator. It's not only a crucial part of the car's electrical system which includes the radio, lights, and fan; but also keeps the battery charged. When cars were first built, small generators were used for their electrical systems.
Alternators are safer than generators and also provide more efficient power to the electrical systems. When the alternator goes bad, the vehicle fails. This is because the battery is used up totally.
When the battery light turns on, there may be a problem with the battery itself, but most of the time, a depleted alternator is the culprit. You can replace it yourself, or you can take the car to a garage.
Garages do stock alternators but it's better if you purchase it yourself. There are many websites for purchasing car parts where you can get quality alternators at low prices.
A faulty alternator has many indicators like dim headlights, starting problems or dead batteries. If there is a problem in the car's electrical system, the alternator is usually to blame.

Tools Needed

There are some hand tools that would be needed to replace a car's alternator like a large flat screwdriver with flat blades, combination and socket wrenches, and vise grips.

Replacing a Car's Alternator

An alternator acts as a charging system on a vehicle. Some alternators may have more amps or may be costlier than others, but all serve the same purpose. It can also be replaced without taking the car to the garage.
One needs to make up his mind on purchasing a new alternator from the car's dealership or purchasing a rebuilt unit from a car parts store, as there can be a substantial difference in the cost.
If a person who is not a professional mechanic tries to replace an alternator, he needs to ensure that he is able to access its bolts. It may sound easy, but it is not, especially in case of a car with front-wheel drive.
Many a time, people who replace the alternator on their own, end up removing other parts instead. It's better to refer to the belt configuration figure which is found under the car's hood or in the owner's manual. You would need this information while reinstalling the belt, be it a serpentine or a single alternator belt.
Make a note of how the alternator is connected to the engine with the help of crayons or markers. It would help you fit in the new alternator accurately, where it is to be installed. You need to concentrate mainly on the adjustment area which allows you to move or swivel the new alternator into the correct position. It also helps adjust the tension of the belt.
Most cars have tensioner pulleys which enable you to make the correct adjustments before tightening the alternator completely. The belt may be a bit hard to remove, in case of front-wheel drive cars because of its placement. Take time to notice wires that are connected to the alternator.
First unplug them all, and then try to remove the bolts which hold the alternator in place. Start with the adjustment bolt, and then with the second bolt. If there is a third bolt, remove it too. However, it's not common to find a third bolt. Once all wires are disconnected and bolts removed, the alternator is free from the engine.
The new alternator can be installed now. Start the installation with the bolt that doesn't allow adjustment. Do not make a mistake of tightening the bolts. Ensure that the alternator is free for necessary adjustments. Replace the belt and ensure that it goes around with the pulleys accurately.
Once the belt is in the correct place, tighten the alternator, and make all needed connections and adjustments by referring to the note that you made while removing the old alternator. You've successfully replaced the alternator.
This can be an easy job if you do the task after referring to a proper guide to replace a car alternator.