In order for an alternator to charge properly, an alternator must be grounded to the engine block. If an alternator has paint or clear coat on the mounting surfaces, it may not be grounded and will not charge. Many mounting brackets are also powder coated, clear coated, painted, or plated. The alternator will not ground properly without a ground wire from the alternator housing to the engine block. (This wire should match charge wire size).

A fully charged battery is at least 12.6V, not 12.0V. A weak/defective battery will cause premature failure. Never disconnect the battery with engine running! This causes voltage spikes that will damage the alternator.