Little Compass RoseCaribbean Compass   April 2003


Bilge Alarms and Couplings

by Chris Doyle

As I returned to the dock in Deshaies today, a drama was in full swing. Les Pompiers were out in force, and alongside the dock a bareboat charter yacht was half sunk. The shaft had dropped out. The charterers had done a fine job to sail in and get help before this turned into a disaster. It served to remind me that for a boatowner, a sinking can ruin your whole day.
For a shaft to fall out is not an unusual event. Many yachts lose shafts, especially if the shaft is spinning all the time. Another common reason for a yacht to fill up with water (and sometimes sink) is that a hose comes off the exhaust, letting the sea directly into the boat. This happened to me once. I had just picked up some charterers and was powering up the lee coast of Grenada. I heard a funny noise, and looking in the engine compartment noticed with horror that the water was so high it was being splashed around by the fan belt. Not good. In this case I was lucky to catch the problem early. We stopped the engine, replaced the hose and pumped the bilge, all the while explaining to the guests that this was a perfectly normal type of running maintenance, something you do almost every day.

It is also not uncommon that hose clamps come off through-hulls, another recipe for disaster.
One of the reasons that boats sink, as opposed to having a wee problem, is that by the time the crew is aware something bad is happening, the boat is so full of water that it is hard to figure out where it's coming from. Often, with water rising over the tops of the bunks, all you can do is abandon ship. Especially if it is the middle of the night and blowing like hell.
Given this, it seems to me surprising, nay amazing, that yachts are not generally equipped with, or required by insurance companies to be equipped with, a bilge alarm. It is so simple - if you already have an electric bilge pump all you need is any electronic alarm wired up so it tells you when the bilge pump goes off. Complete kits are also on sale for about US$70. After the incident I mentioned above, I immediately fitted one on my last boat. It gave me good notice on several occasions when guests had left valves on the toilets in the "on" position.

With almost instant notice that water is coming in, it usually not too hard to pinpoint the problem and deal with it. Installing a bilge alarm should be high on everyone's list of "to do" jobs, way before getting the refrigeration back working and the radar back in action.
Another thought about shafts dropping out. For much of my life my boats had the standard coupling - a rather small fitting which is press-fitted onto the shaft and held in place with a small screw that goes through the coupling into a little dimple in the shaft. When everything is new it works fine. But if the boat is getting old and the parts worn, it is a disaster waiting to happen. To try and prevent this we used to bolt zincs or attach hose clamps on the inside of the shaft, in the dim hope that should the coupling come loose they would stop the shaft abandoning ship entirely. But this is nuts.
When I had to replace my coupling one time I was amazed to discover that for just a few more dollars I could buy a really substantial item, called a split coupling. It was about twice the length of the standard coupling, with a partial split so that it could be fitted easily, and then a bolt pulled it together so tightly there wasn't a chance it could fall off. I wondered why I had never heard about such a coupling before, and why anyone would produce a boat or send someone to sea with the standard model.

Safe sailing everyone!
By the way, communication gremlins ate part of my thoughts about tying to a mooring in February's Readers' Forum. The correct way to attach to a mooring is to put one line through the mooring and bring it back to the same cleat and side as it started on. Then you do the same on the other side with another line. Now you have a double bridle that, unlike a single rope bridle, will not quickly chafe through.

Sign up now and never miss an update from Caribbean Compass. We'll email you a copy of our monthy magazine, as well as other timely updates!


Copyright© 2023 Compass Publishing