A BATTERY PRIMER

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Can there be any sound more disheartening than the faint click-click-click of your
starter solenoid engaging the starting circuit, when there just isn’t enough snort left in the battery to finish the job?

Likely not, but cold weather is here, and we’ll soon be hearing a lot more of that annoying sound in the months to come.

If you’re sitting there listening to the clicks, this may not be your immediate concern, but you should know that a dead battery may actually indicate an altogether different problem. Robert Coates of DJR Service and Truck Repair in
Chilliwack, B.C., says a battery can last almost indefinitely if everything goes well in its service life, but he admits that rarely happens.

“Batteries typically ‘die’ because they’ve been too deeply cycled, too many times,” Coates says. “That means they’ve been drawn down too far by hard cranking, then not built back up again sufficiently.”

As well, a battery can suffer a slow death due to ‘sulphation’, a build-up on the lead plates suspended in the electrolyte, which reduces its ability to produce a charge. Sometimes the plates break, causing a short across the cell, which draws down the rest of the cells within the battery. And eventually the rest of the batteries within a system.

When batteries are connected together, the current flows somewhat like water to equalize the potential from each battery. So if one battery in a four-battery system is only producing eight volts, current will flow from the others to equalize the output, which may equal only 10 volts in total.

But back to our original predicament. Cold temperatures slow down the chemical process within the battery, so if you’ve already got a problem, the cold will only make it worse. Even if you’ve got a fully charged battery in good condition, the bitter cold will cause a battery to lose up to 25% of its charge.

Boost or Bath?
Instinct may tell you it’s time to call for a boost. Good solution, but unless you know somebody, a boost is gonna cost you. If you’re doing it yourself, here’s the proper way to boost-start a truck. Remember that even dead batteries produce a potentially explosive mixture of hydrogen and oxygen gas during charging or
discharging. It’s imperative that you minimize the possibility of a spark near the battery.

1. Attach the positive leads of the booster cables to the positive terminals of the bad battery, using the terminal post that goes directly to the starter, usually the terminal closest to the starter. Then hook the other end of the cable to the positive terminal of the good battery.

2. Attach the negative cable to a point on the dead truck’s frame close to the starter, or to the starter itself if that’s possible. Finally, attach the other end of the negative cable to the frame of the vehicle with the good batteries. Crank the starter.

By hooking up in this manner, you supply current directly to the starter when you turn the key, rather than first charging up the depleted batteries.

If a boost is out of the question, here’s a solution that’ll work, but it may take a few hours. Remove the batteries from the truck and warm them up in a tub of hot
water. Be careful when disconnecting the cables from the terminal posts as the frozen battery cases may crack as a result of forcing the nut.

Don’t allow the water in the tub to cover the top of the battery as this may cause water to enter the battery, or the electrolyte to leak out. You’ll have to refill the tub several times as the batteries will be like 50-lb ice cubes. Keep the water warm and it’ll speed up the process. When the battery cases are warm to the touch, reinstall them, and fire that sucker up. If the wife gives you a hard time about the ring you left in the tub, remind her how much money you just saved. She’ll get over it.

Then there’s always the pull-start method. If you’ve got enough air in the reservoirs to release the brakes, you can roll or pull the truck, with the clutch disengaged and the transmission in fourth or fifth gear. To turn the engine over, just engage the clutch. It probably won’t start right away, so avoid using the brakes and depleting that valuable air supply. A pickup truck will do if there’s no trailer involved, but a pickup will also pull a tractor out from under a trailer if you crank hard enough on the landing gear. But don’t hook your chain to the pickup’s bumper or rear axle.

Engaging the clutch will likely tear it off, so pick a solid spot on the frame.

Borrowing Air
If you’ve got no air, but a friend with a tractor is standing by, you can refill your air reservoirs by connecting an air line to your wet air tank, the first tank in line from the air dryer, with a gladhand fitting and a shut-off valve. Connect the gladhand to your friend’s service/supply line, the red one, and have him press the red button on the dash, This will supply 120-psi air to your air tanks so that you can release your brakes.

It’s a very good idea to install an air line, as I’ve just described, the day you get the truck home from the showroom. Mount the gladhand fitting permanently on the
frame somewhere that’s easily accessible. You’ll never know when you may need it.

If you suspect your batteries are weak, park the truck on an incline whenever possible, so if you have to, you can roll-start the truck without the aid of a pull.

Keep it Warm
If you plan to park the truck for a day or two in severe cold, you might consider using a battery charger set to slow charge to keep a trickle of current flowing into the batteries. This will keep them warm as well as maintaining the charge.

Keeping the engine warm with a block heater will make it easier to start, but even a warm engine won’t turn over if the batteries aren’t up to the job.

Most auto parts stores sell battery warmers. They’re essentially heating pads, which wrap around the battery. I’ve used them successfully on my car battery, and I’m sure they’d work on a truck, but you’d probably need about half a dozen of them before they’d do any good. It depends how desperate you are, I guess.

It’s always a good idea to have the batteries checked, by somebody who knows what they’re doing, as you head into the season of peak demand. If the check reveals an underachiever, Coates suggests a thorough examination of the charging system, beginning with the alternator. But more often than not, he says the problem lies in the cables and the connections.

Another good survival plan for winter is to run a set of batteries with a high Cold Cranking Amp (CCA) rating – that’s 900 or more, and as high as 1250, but you’ll
pay for the security. These batteries deliver a stronger punch for a longer time in cold weather. But a word of caution is necessary here: being able to crank for
longer may increase the possibility of frying the starter. Just because you can, don’t ever crank the engine for more than 30 seconds without allowing the starter to cool for at least two minutes between attempts.

Remember, don’t just replace a dead battery, because a bad one is probably only the symptom of a bigger problem.

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Jim Park was a CDL driver and owner-operator from 1978 until 1998, when he began his second career as a trucking journalist. During that career transition, he hosted an overnight radio show on a Hamilton, Ontario radio station and later went on to anchor the trucking news in SiriusXM's Road Dog Trucking channel. Jim is a regular contributor to Today's Trucking and Trucknews.com, and produces Focus On and On the Spot test drive videos.


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