The alternator is the heart of the electrical charging system in a Volkswagen. The alternator makes use of the rotation of the motor to create electricity, which it then sends off to the battery and to the electrical system. When the alternator fails, so will the battery and the electrical system. In this case, the project vehicle is a 2005 Volkswagen Beetle, but the process of removing an alternator is similar for other Volkswagen vehicles, as well.
Open the bonnet to access the engine compartment. Take off the negative post from the battery with a wrench, then take off the positive post. Unbolt the undercover from the engine, using the 3/8-inch ratchet and socket. Remove all connections from the alternator with a wrench.
Loosen the alternator bolts from the engine block. Push the alternator towards the centre of the engine. Pull the belt off the alternator pulley, then remove the alternator bolts completely and take the alternator out of the engine bay.
Set the replacement alternator in the engine mounts, and install the bolts, but do not tighten them yet. Place the belt around the replacement alternator's pulley, then pull the belt away from the engine while tightening down the alternator bolts. Reconnect the electrical connections on the alternator.
Reinstall the engine undercover, using the 3/8-inch ratchet and socket, then reconnect the terminals on the battery, starting with the positive one.