Replacing an alternator can typically be achieved with some basic tools and a methodical approach to the job. The first step to take when replacing an alternator is to disconnect the battery in order to avoid any chance of an electrical short. Once that has been done, the alternator belt can then be removed along with any brackets that are in the way. Before installing a new unit, it is a good idea to line up the new pulley with the old one to ensure that it is correct. After replacing an alternator, it is also a good idea to ensure that the battery is fully charged and that all the connections are clean before starting the engine.
Some alternators are very difficult to reach and may require the removal of an engine mount or other complicated procedures. In some cases, various brackets or other components may need to be removed. Some alternators slip right out after a few bolts are removed, but many others are difficult to reach since they are located in cramped quarters. The actual procedure for replacing an alternator is quite simple, and as long as a few general tips are followed it can usually be done without too much difficulty.
The most important step to take before replacing an alternator is to disconnect the battery. If this is not done, the positive cable to the alternator may touch ground and short out. This could potentially damage the computer or even cause a fire. It is also a good idea to charge the battery up, test to ensure that it is in good shape, and clean all the connections. This is due to the fact that a bad battery can place extra stress on the new alternator.
It is often a good idea to examine the belt when replacing an alternator. Since the belt has to come off before the alternator can be removed, putting on a new belt at the same time involves no extra effort. If it is a serpentine belt, it is also a good idea to make note of the way it was wrapped around the pulleys. Serpentine belts can often go back on in two or more configurations, only one of which is correct.
When removing the bolts that hold the alternator in place, it is a good idea to make note of where each one came from. Each bolt may be a different length or thread pitch, so they need to go back into the same positions they came from. The pulley on the new alternator may also be different from the old one, so it is good to check that before reinstalling. An incorrect pulley can cause a v-belt to walk off or it may shred a serpentine belt. In many cases, the old pulley can be transferred over if necessary.
