If your car battery will not hold a charge despite repeated use of jumper cables, a new battery may be needed. Failure to start or a reading below 12.4 on a voltmeter is a good indication that replacement is necessary. However, you don't need a mechanic to accomplish this task. It is merely a matter of cleaning the terminals, removing the battery and dropping in a new one.
The terminals on your battery can become dirty and corroded. You must remove the debris before installing a new battery. In some cases, a good cleaning may resolve your battery troubles, eliminating the need for replacement.
Make a solution out of baking soda and water to pour over the terminals to dissolve the corrosion. Approximately four teaspoons of baking soda in two cups of water will do the trick.
Pouring a baking soda-based cleaning solution on the battery terminals may not be enough to remove build-up. You might need to brush down the terminals to completely rid them of corrosion. Get a wire brush to thoroughly clean the battery tray, the terminal clamps and connections.
An adjustable wrench is the easiest tool to use for battery removal and installation.
Adjust the wrench to fit any security bar or strap that may be holding your battery down. Loosen the bolt and then adjust the wrench to fit the terminals. The terminal clamps may be tough to budge at first, but they will come off fairly easily once loose. Remove the terminals from the old battery and lift it out. Place the new battery in the slot and reconnect with the wrench, attaching the negative terminal first.
If your battery is the side-post variety, the bolts may be much more difficult to reach. In this instance you may need to go to an auto parts store and buy a side-post wrench.
Protective wear is important when dealing with a car battery. Because sparks and electrical current are possible, it is a good idea to wear goggles and gloves when completing this task.
