Jump-starting
a dead battery
By Tom Morr
TIPS & TRICKS
STANDARD-DUTY
BATTERY MAINTENANCE
FOLLOW THESE EXTRA maintenance
tips for standard-duty batteries.
• Make sure to wear safety glasses when
working near or with car batteries.
• Check the water level every couple of
months. It should be just touching the
bottom of the refill hole.
• Refill the battery, when needed, with
distilled water. Don’t use tap water, which
produces corrosion on the terminals.
• Don’t overfill the cells. Just to the bottom
of the refill hole is perfect. A
WHEN THEIR CAR BATTERY DIES, many people would rather call for
roadside assistance than lift their car’s hood. However, jump-starting a car
yourself can be more efficient than waiting for help. Here’s how to do it.
Step 1: Select the right cables
Cables are a prerequisite for jump-starting a vehicle. The thicker the
cable, the more electrical current can flow. Quality cables are available in
thicknesses ranging from 10- to 2-gauge (the smaller the number, the larger
the cable). Ten-gauge is usually sufficient for starting batteries in four-cylinder
vehicles in warm weather. As the size of the engine increases and temperature
decreases, fatter jumpers will do the job better.
Large motor homes or farm implements that need jumping in northern
Minnesota in January are best served with 4- or possibly even 2-gauge cables.
Thicker cables will also stay more flexible at colder temperatures.
A word of warning: If the cables get warm during use, it’s a sign of too
much resistance. Either the cables are too thin for the job or they’re possibly
frayed or have rusty clamps.
Cable storage is critical. During jump-starting, the cables’ jaws often
pick up battery acid from corroded terminals. This acid is highly corrosive,
so cables should always be cleaned and stored in a bag.
MAINTENANCE-FREE
BATTERIES
A MAINTENANCE-FREE BATTERY, similar in
design to a conventional automotive battery,
is really just a heavier-duty version of the
same arrangement. Many of the components
have thicker construction, and different, more
durable materials are typically used. For
example, the plate grids often contain
calcium, cadmium or strontium, to reduce
gassing (which causes water loss) and self-discharge. This design is called a lead-calcium
battery. The heavier-duty parts ensure that
fluid loss is kept to a minimum and that
components have a much longer life, making
it a closed system. A
Step 2: Prepare for the charge
First, inspect the dead battery. If it’s leaking excessively or the case is
visibly cracked, abort the jump-starting mission and replace the battery. A
damaged battery won’t hold a charge anyway. Besides, attempting to charge
a battery that has a split case can eject acid, and your eyes or your skin could
be seriously injured.
Inspect the battery terminals. Corroded studs and battery-cable ends will
impede the flow of electricity from the jumper cables into the battery, so clean
the posts and cable ends as well as possible. Remember to keep even dried
battery acid away from skin, eyes and lungs. Wearing eye and skin protection
is always advisable whenever dealing with batteries.
Park within jumper-cable distance of the dead car. Make sure that the cars
aren’t touching. Both vehicles should be put in “park” (automatics) or “neutral”
(manuals) with the parking brakes set and all accessories such as headlights,
dome lights and radios off. Turn both ignitions to the OFF position. Unplug any
cigarette-lighter accessories such as radar detectors and cell phones: Jump-starting can send a voltage spike through the vehicle’s electrical system and
burn out these gadgets.
Identify the batteries’ positive and negative posts. Then prepare the
jumper cables by uncoiling them and separating the positive and negative
clamps. Remember that red or orange is positive and black is negative.
