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Published: January 2013

Making Sure Batteries Don't Go Boom

When the owner of this battery turned the key on his 27-foot Wellcraft after a pleasant couple of hours ashore, he thought someone had sabotaged his boat (Claim #1214339). "I heard the starter click and then, 'Kaboom!'" he told Seaworthy. The sulfuric acid that spewed out was largely contained within the engine compartment, but the owner destroyed his clothes cleaning it up. The deep-cycle battery was only a few months old, and it had been installed and topped up by the boatyard. BoatUS referred the owner to the manufacturer, who refunded the purchase price. The owner wanted to make sure others were aware of what can happen if a battery explodes.

Photo of an exploded battery

Battery explosions like this involve two things: hydrogen gas and a spark. Hydrogen is the lightest of the elements, so it will disperse quickly if it is released into a ventilated space. In this case, the battery had been installed with plenty of ventilation as the American Boat and Yacht Council (ABYC) recommends. It was located in a spacious engine compartment with two air vents right above it. The couple of hours between turning off the engine and starting it again should have dissipated any hydrogen gas. The alternative is that hydrogen gas built up inside the battery case and an internal spark caused the explosion. This could happen if the electrolyte levels got so low that the plates were no longer covered, or if the vent was clogged, allowing hydrogen to build up.

The battery had been kept on a shore charger when the boat was in the slip, and the owner had not thought it necessary to check the electrolyte because the battery was almost new. According to marine author Nigel Calder, "If the battery has not been topped up since the first installation, and if it had been overcharged repeatedly since then (maybe plugged into shore power with a charger that was malfunctioning or had too high a float setting), it may have been substantially boiled dry." Trojan, a manufacturer of deep-cycle batteries for golf carts, recommends topping up a new battery monthly until you get a good idea of how "thirsty" it is.

So make sure your deep-cycle batteries are in a well-ventilated space, check the electrolyte levels regularly, charge it using a marine charger with a regulator, keep grease and other contaminants away from the vents, and watch out for bulges in the battery case, which indicate a buildup of hydrogen gas. If you prefer a lower-maintenance solution, the next time you need to replace your batteries, you might want to switch to AGM or gel technology, as this owner did. But don't assume you don't have to do anything -- even those batteries are not maintenance free.

Wet Sand And Aluminum Don't Mix

Photo of sand in bilge

The owner of this 2002 23-foot Pacific Boat, an aluminum center-console skiff, couldn't figure out why holes kept developing along the keelson on the bottom of the boat. After fixing several with epoxy, he put in a claim with BoatUS (#1213765). He was the third owner of the vessel, and he told the surveyor he towed it to Baja, Mexico, and launched it from the beach.

The surveyor found a large amount of wet, sulfurous-smelling sand in the after reaches of the bilge that led to poultice corrosion. This relatively common type of corrosion occurs when wood, dirt, or fluff (any material that can hold and wick moisture) comes in contact with the aluminum surface. If this detritus stays dry, the situation is relatively benign. However, when the material becomes wet, the aluminum surface beneath the material is starved of oxygen and it cannot build up the layer of oxidation necessary to protect the aluminum from corroding.

Sand accumulated in the hollow keelson along with any water that came into the boat, and the water/sand mixture sat there because there was no way to access the area to clean it and no bilge pump to remove the water. Since BoatUS policies do not cover wear, tear, and corrosion, his claim was denied. If you have an aluminum boat, make sure to keep the bilge clean and dry in order to avoid this problem. If access is difficult, figure out a way to improve it.

Alcohol And Boating

Seaworthy has discussed the issue of alcohol and boats many times, but an incident in New york and a conviction in California highlight the increasingly serious view law enforcement and the courts are taking of boating under the influence (BUI).

In September 2012, a driver in a deadly boat crash in New York state was indicted for vehicular homicide -- a charge usually reserved for the worst cases of intoxication and recklessness on highways. Prosecutors say 27-year-old Brian Andreski was under the influence of alcohol and cocaine on June 23 when his 25-foot speed boat slammed into a fishing vessel in Long Island's Great South Bay, killing a fisherman heading for a shark-catching tournament. A grand jury indicted Andreski on the charge of aggravated vehicular homicide, a felony previously used only in motor vehicle crashes on land. If Andreski is convicted, he could face up to 25 years in prison. The tragedy spurred legislators to call for tougher laws for BUI in New York and resulted in BUI crackdowns by Long Island police last summer which are likely to continue next summer.

In October 2012, a judge handed down the first murder conviction in a BUI case in California and, as far as we are aware, in the nation. The defendant, 25-year-old Justin Ennis, cried openly in the courtroom as a judge sentenced him. In August of 2010, Sal Rodriguez and an adult friend were out in Rodriguez's boat celebrating a child's birthday. Rodriguez, a soon-to-be father, had stopped to pick up one of the children and an inner tube when he saw Ennis racing toward him in a powerboat. Rodriguez tried to start his boat and move out of the way, but he was too late. "Mr. Ennis spent the day drinking, and one hour after the collision, he was [at] a 0.12 blood alcohol," Deputy District Attorney David Wolf said. "In addition, he had marijuana in his system." Ennis was sentenced to 15 years to life in prison for second-degree murder.

Beware Bad Fuel

Captain Stanley Bull Dog Thal of BoatUS Pro Captains Delivery Service wrote us with some advice for anyone heading offshore with a diesel engine. He pointed out that diesels are notorious for being finicky about algae and water, and that taking an older boat that has been sitting at a dock for years into open ocean waves and swell will stir up the tank and can easily result in clogged filters. "More so than any time in the past, we are discovering accumulations of bad fuel on delivery vessels," perhaps because so many boats have been left on the hard or in their slips due to the bad economy.

Photo of a centrifugal filter manufactured by Racor

To avoid fuel problems, install a centrifugal filter, such as those manufactured by Racor, between the diesel tank and the engine in an easily accessible place. These are considered primary fuel filters while the small filter on the fuel pump is a secondary filter. Many serious offshore boats are equipped with two Racors just to be sure. Thal adds, "Stock up before you go offshore with no less than three complete sets of primary and secondary fuel filters for the engine, and don't forget three sets for the generator." Another suggestion: Have your fuel polished before heading offshore if your boat has been sitting for a season or more. Many companies have mobile polishing units they can bring to your marina. That could save you a lot of unnecessary frustration at the worst possible time.End of story marker

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