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Reversing Charges

Every spring, we see claims involving electrical fires and damage to sensitive electronics that are the direct result of owner error: The battery cables were reconnected backwards, with the negative wire connected to the positive post and visa versa. Sounds like something too basic to mess up, but rewiring the batteries can be particularly complex if you have to remember whether your batteries are wired in series or in parallel and which wire goes where. These claims are entirely preventable, and our goal is not to have any next spring. So if you're going to remove the boat's batteries this fall to trickle-charge them over the winter, take precautions now. Before you remove the battery cables, take a picture with your phone and send it to yourself or store it somewhere on the phone where you'll be able to find it again. Then, clearly mark which cable goes where. Write a + or — (and the number of the battery) on a piece of tape attached to the cable or use black and red electrical tape to distinguish them. A dab of red fingernail polish on the positive lug of the battery and black on the negative will also help you keep things straight.

A Pump That Won't Pump

We've said it before, but it bears repeating: Bilge-pump failures don't sink boats, leaks sink boats. In most cases, a bilge pump is designed to remove nuisance water from a boat, not a steady stream. If you leave your boat in the water this winter, a bilge pump might buy your boat some time if it begins leaking (especially if there is also a high-water alarm that might alert someone that there's a problem).

Photo of a bilge pump with stuck switch

But if your bilge pump can't function due to poor wiring connections, loose clamps or leaking hoses — or worse like this stuck switch — you might get a call this winter that starts something like: "We've got some bad news ... "

Blowing Off Steam

There doesn't seem to be much that can go wrong with a lowly water heater — after all, there are no moving parts. But water heater controls can fail, and when they do, it's possible that the heating elements won't turn off and the tank can build pressure. Too much pressure, and it can explode. That's why water heaters have over-pressure valves that "blow off steam" before the tank can rupture. In boat installations, sometimes the piping from the over-pressure valve leads to the bilge or somewhere else where escaping scalding hot water won't hurt anything. But there should never be a valve on the escape piping, as in the picture at right. What's even worse is that the valve is closed, effectively rendering the safety device inoperative.

Inspecting Drive Belts

Losing a drive belt can ruin a day on the water. A worn belt is subject to failure at any time, which can lead to losing your alternator or your power steering or to an overheated engine. When you're laying up your boat this season, check each belt. Look for cracks or obvious worn spots like the one in the picture above. If you see black dust near the belt, it probably means it's not wearing right and needs adjusting. A belt that is too loose will slip — and usually squeal to let you know. One that's too tight will wear too fast and may even damage the bearings on whatever it's turning. A properly tensioned belt should deflect about a half-inch per 12-inch span when pushed hard in the center. Keep a spare of each belt onboard, as well as the tools necessary to replace it it. It's usually not a hard job, and it can save you from being stranded. Some boats have a single, long serpentine belt that drives everything, but these tend to be a bit more complicated to change.

Securing Sails

Name one sailing area that doesn't sometimes have a lot of wind during the winter months. Not easy, because over the winter there are almost always thunderstorms, nor'easters, or just plain winter storms that can produce damaging winds. Sailors love wind, of course, but too much can be a bad thing, especially when the boat's fending for itself on the hard, on a mooring, or in its slip. Wind has a way of finding a little opening and making it bigger. A loose jib is just asking for storm winds to unfurl it, which will almost certainly damage the sail and possibly the rig. If the boat's in a slip, a loose jib can damage the boat next to you. Removing the furling jib should be a standard part of winterizing any sailboat. But if you decide not to take our advice, at least make certain that the furling sail is secure and can't come undone. Lock or tie the furler drum so it can't move, and truss up the sail with the sheets until it is well secured and can't get loose. While you're at it, take that mainsail home with you as well. This is a perfect time to see to all those little broken stitches and chafed areas so your sails will be ready to fly come spring.

— Published: October 2015

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