Car Repairs: How to replace an Alternator

Car repairs can be a breeze with the right repair manuals. Change your alternator today

Learning How to Install an Alternator with Quick Car Repairs


When the alternator needs replacing, the signs are very noticeable. Fortunately, this is one of those quick car repairs that can be done on a whim. According to the repair manual that explains the ins and outs of alternators, the car will start up, but it will not run far before it shuts down, and the cut off happens almost instantaneously when you turn on the headlights or even the radio. Most people think that replacing the alternator is a job reserved for the professionals only, but this is one of those car repairs that can easily be done by the average Joe and the process is very straightforward. By using an auto repair manual sold online, or a repair manual that can be purchased by the dealer, you can feel confident about fixing your car yourself and know that it was done correctly.

Removing the Old Alternator

The first step of installing a new alternator is removing the first one, which requires the engine to be turned off and cool to the touch. Use car repair manual to identify the location of the alternator and the mounting brackets that are holding it in place. These brackets must be removed first and foremost, and the repair manual will provide instructions on how to do that. Once the brackets are removed, the next task is to disconnect the negative terminal that runs from the battery. The negative terminal is black, and disconnecting it will prevent you from shorting out wires and damaging the electrical currents that run throughout the vehicle.

Next, loosen the two bolts that hold the alternator in place on either side, but do not remove them. Loosen the slack of the V-belt that runs across the alternator’s pulley by rotating the alternator in the same direction that the belt runs. Before you completely remove the alternator, you must refer to your repair manual to determine if the electrical wires that are held in wire retainers or nuts and bolts so that you can remove them.

It is important that when you take the wires out, you create markings of some sort so that you know exactly which wires go where when you install the replacement alternator according to the car repair manual. Now you can completely remove the loosened bolt in order to remove the alternator, and then place those bolts into the identical housing of the replacement alternator so that it is ready to be installed according to the instructions found in the repair manual.

Installing the New Alternator

While positioning the replacement alternator so that the bolts are aligned with the holes of the engine brackets, which make it easy to feed the bolts through the holes, and finally place the washers and nuts to the back of the bolts. Next, align the V-belt so that is correctly in place on the engine pulleys, then put the belt on the alternator pulley. Position the alternator the way it will be reattached to the car. Set the tension of the V-belt by rotating the alternator in place until the V-belt is properly aligned, having no visible slack, then hand-tighten the bolts into the brackets.

Finally, adjust the jaws with a pair of vice grips and ensure they are tight in the slotted bracket. Use the vice grips, positioned on the slotted bracket, to hold the alternator in the proper position against the V-belt.  This will allow you to adjust the tension of the belt until it is just right. Then you must pull the alternator an extra ½ inch, making the belt tension even tighter. That is when you readjust the vice grips to hold this specific position of the alternator, then completely tighten all the bolts to secure the alternator in place. Once you remove the vice grips you have now successfully completed one of many quick car repairs.

Test the Alternator to Make Sure It Operates Correctly

The only thing left to do is to test the engine by starting the car. Make sure that you do not hear any squeaking noises and that the ignition warning light is not illuminated after the car has been started. If you do hear squeaking, that means the belt is too loose and needs to be tightened. Just be careful not to over-tension the belt, as the repair manual will instruct you, or you can cause significant engine problems. Fast car repairs are easy, cost effective, and can be done by most with basic skill levels. If you can read and follow directions, then you can perform quick car repairs.