Replacing Car Alternator

Replacing a car alternator is something most people can do without too much aggravation. I know, famous last words.

A car alternator is the device that converts the energy produced by an engine into usable electric current. This current is used for different purposes depending on the make and model of your. Common purposes include charging the battery, headlights, radio and so on. The alternator is really a two part component. The first is a belt that connects it to the end of the crankshaft on the engine. This belt spins when the engine is on. The spinning motion turns magnets in the alternator, which creates the electrical current.

The first step to replacing a car alternator is to get a pen and paper. Most cars now have a host of electronic components. Many of these will go completely dead when the battery and alternator are disconnected during the replacement process. As a result, you need to write down any anti-theft codes, setting and what have you. Trust me, I’ve failed to do this and ended up with problem where my key code was rejected by an ignition security system. Not fun.

The next step requires you to disconnect the battery cables. The alternator is an electrical component. Electricity always needs to be respected. Always! Disconnect the battery and then identify the alternator. Now you should see electrical cables running out of the alternator. Disconnect the ground and then the hot cable. Secure them out of the way.

Now it gets fairly easy. You need to remove the serpentine belt first. There is usually an adjustment mechanism where the belt connects to the alternator. You can usually loosen a bolt and slide the alternator towards the engine. The belt then goes slack and you can remove it. Make sure to give the belt a close inspection. It may be part or the entire problem.

The next step in replacing the car alternator is to simply remove it. This is done by removing the bolts holding it. Depending on your car, there may be two or three of these. They are big and hardy, so you should be able to see them. Just pop them off and the alternator should lift out of the cradle it sits in.

At this point, you can take the alternator to a parts store and have it tested. Doing so will let you verify the alternator is actually the problem. Assuming it is, you can also be sure the replacement alternator is a match. Now just head home and repeat the process in the opposite order and you will have replaced a car alternator.

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