HDABOB's Tech Notes:

Do you ever wonder how the charging system works?

Let me explain it to you...

The components of the charging system consist of:



Voltage regulator

Charge light



The BATTERY is the electrical storage device that allows the starter to start the engine. If the battery is low, the engine cannot start. Batteries usually last about four to five years. Modern batteries do not require maintenance. The battery terminals, however, do require periodic cleaning.

The ALTERNATOR is the device attached to the engine, driven by a belt from the main pulley at roughly one half engine RPM. Most alternators have a VOLTAGE REGULATOR built into the main assembly. This voltage regulator converts the 110 Volts AC and about 70 amps to 14 Volts DC, maintaining the same 70 amps. This power is then stored in the battery for future use. The alternator doesn't require periodic maintenance except for occasional belt replacement or tightening.

If the voltage output of the alternator is below 12 volts DC, the CHARGE LIGHT on the dash comes on. When this light is on, the battery supplies power only. Since the battery is of limited duration, all nonessential functions must be discontinued. The battery will only last several minutes if anything more than the engine is running.

 When it becomes necessary to jump-start a dead battery, the source of the power drain from the dead battery should first be checked. Then check to see if the battery acid is frozen or low. If frozen, the battery could explode if attached to another battery. If battery acid is low, the battery could be damaged by heat buildup inside the battery.

Make sure vehicles are not touching. Jumper cables should be hooked up to the good battery first, making sure the other end of the cables are not touching. Then the positive (red) terminal should be attached to the positive terminal of the dead battery. Then the negative (black) terminal should be attached to the engine or as close to the starter as possible, not on the dead battery. The car with the good battery should be started first and allowed to run for about two minutes, then, the car with the dead battery can now be started. Disconnect the positive cable from the dead battery first, then the negative. Then both cables on the good battery. Allow the car with the dead battery to run for at least half an hour to charge it back up. Longer running is better to fully charge the battery.

 HEADLIGHTS and running light are made to be durable and bright. The headlights usually consist of a sealed beam inside a lens assembly. Newer car headlights are made with replaceable bulbs that are very bright and are designed to be easily replaced without replacing the lens of the light. To replace a bulb in a headlight… locate and remove the bulb by turning the locking ring and removing the old bulb and replacing a new one in its place. Care must be taken not to touch the glass part of the bulb, because the oils from the hands will cause the bulb to burn hotter, burning out sooner. If the glass is touched, the bulb must be cleaned off with alcohol to remove all the residue.


...and that's the way the charging system works!!

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HDABOB's Mobile Service 12/16/2004