How to properly maintain your classic’s battery

You’ve been waiting for this drive all week. You turn the key and instead of a V-8’s roar, the only sound your car makes is click-click-click-click. Venturing into your garage for an early morning drive only to hear the sickening whine of a dying starter motor puts an anticlimactic end to any driving adventure before it begins. Maintaining your lead-acid battery is not vintage motoring’s most exciting aspect. Unfortunately, though, it is necessary for classic cars that might sit dormant for long periods of time between excursions. Weeks and months of downtime can result in battery discharge. The good news is that maintaining a battery is easy and inexpensive.

The wet cell lead-acid battery hasn’t changed all that much since its introduction in the 1800s and neither has the maintenance of adding distilled water, cleaning up corrosion and charging. Lead plates inside the battery react with electrolyte or battery acid to store and discharge electricity. Sulfuric acid vapor and hydrogen gas can exit the battery vents as a byproduct of charging. Resulting battery terminal and post corrosion can interrupt incoming and outgoing current flow. Cleaning up the terminals and posts can help keep corrosion at bay. Corrosion, time, cold temperatures, mystery shorts or a recalcitrant map light can discharge a battery between drives.

Modern lead-acid automotive batteries offer more cranking power, longer life and less maintenance – thanks to sealed cases – than traditional batteries. But even Absorbed Glass Mat (AGM) and Gel batteries, both of which stabilize the electrolyte and eliminate adding water, still require periodic post and terminal cleanup. Classic car purists often stick with the traditional-appearing, basic black lead-acid battery for aesthetic reasons. Spending time and money on a period-correct restoration and bolting in a Day-Glo pink topped Extreme 2000 battery under the hood just isn’t right. Original-appearance or restoration-specific AGM and Gel batteries are available, but chances are great that a wet cell lead-acid battery provides your classic car’s spark.

Assuming your car’s charging system is in working order, avoiding a dead battery in the dawn before cars and coffee or at sunset after a long and winding drive is simple. Maintain and clean the battery terminals and posts. Add distilled water to the cells as needed. Charge the battery using a 2-10 amp charger after a load or voltage test. If your classic car or motorcycle sits under cover or in the garage for extended time periods, nothing beats the slow or trickle charger – a determined device that not only keeps the battery charged but also helps prevent battery-killing sulfation. Exercise through charging and occasional rest is a good cycle. With proper care and maintenance your lead-acid battery can provide years of faithful service.

Posts and terminals clean up with this inexpensive tool. One side of the tool cleans up terminals, the other side…

The other side of the tool is made for cleaning battery posts for improved contact.

Dielectric grease helps prevent new corrosion, repel water, and improves contact.

Low electrolyte levels can wreck havoc. Add distilled water to the cells. Do not overfill.

A battery load tester checks voltage and simulates a heavy current draw.

The automatic battery charger brings the battery back to a full charge quickly.

Slow or trickle chargers maintain battery charge and can prevent battery-killing sulfation.

A 1-lb. baking soda to 1-gal water solution neutralizes acids and helps prevent corrosion.

The slow or trickle charger is ideal for use if the car sits for long periods between drives.