Safety Warnings And Alerts

From BoatUS Marine Insurance

AIS Woes

The automatic identification system (AIS) is a great tool used for avoiding ships, but relying on a third-party AIS website or app to see ship traffic isn't the same thing. A true AIS system transmits a vessel's position and speed (along with other identifying information) to other AIS systems within VHF range. Class B AIS systems, designed for recreational boaters (who can also use Class A), will show other vessels, including big ships, on a screen so you can take action to avoid them.

Big ship near a small boatPhoto: BoatUS Marine Insurance

However, the websites and apps that collect that information and show it on a laptop, tablet, or phone aren't always accurate and don't always show every AIS-equipped vessel. Depending on one, or assuming it's as accurate as a shipboard AIS, is a mistake. At best, the websites and apps are supplements to sound navigation and shouldn't be relied on.

Lithium-Ion Batteries And Automotive Chargers

Lithium-ion batteries are slowly making their way into recreational boats. Li-ion batteries, as they are known, can weigh 75 percent less than conventional lead-acid batteries and can be charged very quickly — but not by using a standard automotive charger or even a standard marine-battery charger. Li-ion batteries are very sensitive to charging, and with the wrong charger, they can go into a thermal runaway: a meltdown and fire.

Most Li-ion battery manufacturers sell or require very specific chargers that must be used with their products; failure to do so can easily cause a fire. Before you even consider installing a Li-ion battery, be certain that you've got a manufacturer-approved charging system.

What's Under Your Stuffing-Box Hose?

Hoses, like anything else on a boat, have a limited life span. Failing to replace worn hoses usually leads to a leak and, possibly, a sunk boat. While most hoses are pretty easy to check by looking at and squeezing them, stuffing-box hoses are a bit harder to judge, and most people can't tell you how old theirs are. But it's not just the hose that needs inspection.

These pictures show what's under a perfectly fine looking stuffing-box hose. The second picture shows that the shaft log was being eaten away by corrosion and likely didn't have much time left before it failed and caused a real leak. The rule-of-thumb life span for stuffing-box hoses is 10 years. If yours is older, it's time to replace it and see what's underneath.

Gasoline Gaffs

Gasoline leaks are not something to take lightly. Even a small dribble generates enough fumes to cause an explosion, which is why we're constantly reminding you to inspect your fuel system regularly (a thorough examination every spring and a quick look a few times a season).

This picture conveys both good news and bad news. The good news is that after discovering a leak in his fuel tank, this owner replaced all the hoses. The bad news is that rather than removing and resealing a leaky fuel full flange (probably the reason for the leak in the first place), the owner simply spread some black sealant around it. The sealant turned into black goo after gasoline attacked it and still allowed gas to seep around it. The fix requires removing the flange and rebedding.

One more thing: While replacing the hoses was a good idea, the owner used Type A2 hoses, but Type A1 hoses are far sturdier and will give the owner more time to fight a fire or abandon ship because they burn slower.

Shore-Power Fails

If you were walking down the dock and saw this shore-power pedestal, you might just shake your head and keep going. But the right thing to do is alert the marina that something's not right.

In this case, someone didn't have a proper shore-power cord, so he or she simply cut the ends off an extension cord and jammed the bare wires into the receptacle, before "tidying up" the job with some tape. Worse, the culprit completely ignored the ground wire, which is designed to protect people from electrocution — something all too likely to happen with this "installation." If you see some creative shore-power setups, notify marina management right away.

More Wiring Fails

Not long ago, a study of the BoatUS Marine Insurance claim files revealed that wiring faults are responsible for most boat fires. This example, complete with electrical tape and wire-nut connections, is ripe for a major fault, which is likely to start a fire. Even if it doesn't, imagine trying to troubleshoot an intermittent electrical fault with this as your guide. 

— Published: February/March 2017

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