Boater Alerts And Warnings

From BoatUS Marine Insurance

What To Do About Halon

A lot of older boats still have halon fire extinguishers on board, and there's a lot of confusion surrounding these systems. Halon, short for halogenated hydrocarbon, is a liquefied compressed gas that is a very effective fire suppressant. It will put out almost any kind of fire and does so without damaging electronics.

It's a common misconception that halon is illegal. It's still legal to have a halon fire-suppression system on your boat, but because of Environmental Protection Agency regulations due to the damaging effect of halon on Earth's ozone layer, these systems haven't been produced in the United States since 1994.

By now, these legacy systems are getting pretty old, so what do you do if your boat still has a halon extinguisher on board? These systems, which are usually automatic engine-room extinguishers, should be inspected every year by a qualified fire-extinguisher technician. If you choose to do it yourself, look for hardware damage that could render the system unusable, and have your canister weighed. That's the only way to tell if it's still serviceable. Halon canisters are labeled to show their weight when full and the weight at which they must be replaced.

Even though it's not possible to buy new halon, there are companies that legally sell recycled halon and can refill yours, though it's expensive. These same companies will buy halon and usually sell newer-style halon-system replacements, such as Halotron. Search "halon" online to find companies that can do this.

Scupper Trouble

Many boatbuilders fit their boats with plastic cockpit scuppers and drains. Plastic is subject to degradation by the sun and may crack over time as a boat flexes. A cracked or broken fitting can allow rainwater to drain into the bilge, which can make the boat so low in the water that it backfloods through the fitting. The fitting pictured is only 5 years old, but already it has broken off inside the bilge. Inspect your cockpit drains this spring and periodically throughout the year. Sometimes they're hard to access, so a good mirror or even a small camera can make the job easier.

Impeller Fail

Cooling-water impellers should be replaced at least every other year. While these rubber impellers are pretty durable, any time your raw-water intake is close enough to the bottom to ingest mud or sand (like this one), they should be changed. Sand, as you might guess, is pretty tough on not just the impeller but also the housing; you might have to replace both if the pump was full of sediment and run for a while. The picture on the right shows the end result of waiting too long to replace an aged impeller. Note that many of these pieces had to be fished out of the heat exchanger after the boat overheated — not an easy job.

Look Up!

Trailer-sailors can be pretty hardcore and will put a boat into pretty much any sailable body of water. But boat ramps designed for fishing boats and runabouts may not be safe for sailboats. The owner of this boat had just put up the mast and was waiting patiently in line at the ramp. As he pulled forward, he heard a bang. The whole mast came down after catching on an overhead light pole.

Other more dangerous BoatUS Marine Insurance claims involved trailerable sailboats that struck low-hanging power lines, in some cases causing the boats to catch fire. Other instances of contact with power lines have resulted in electrocution.

If you're bringing your sailboat to a new place, stop and look around for low branches, light poles, and wires that may run across your path to the ramp. In some instances, electricity can even arc from power lines to a mast that is close enough, even when there's no direct contact.

Red-Hot Turbo

Diesel engine turbochargers operate at temperatures of up to 1,200 F. These are normal operating temperatures. Should one of these diesels overheat, as engines sometimes do, the temperature may rise even higher. The boat in the photo burned and sank after the turbocharger overheated, probably due to lack of lubrication. It's possible that the turbo's heat-shielding blanket was old or even oil-soaked, which may have then caught fire.

Thermal shields must be renewed periodically (Yanmar recommends every 250 hours on its engines) and leaks fixed promptly to avoid fires. Hoses that are leaking or otherwise suspect must also be replaced. All surfaces less than 18 inches above the turbos should be insulated. Hoses should be secured well away from the exhaust system. Use metal straps; plastic will melt. 

— Published: April/May 2017

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