Common gear failures

Most voyaging sailors agree that electronics are the most fail-prone system on board – particularly interfaced electronics of unproven manufacture. Include among them chart displays combined with GPS and single-screen apparent/true wind/boat speed/ depthfinders. In some cases problems occur because of poor design and components, in others because the units were wired on the boat with wrong fuses of excessive rating. In order to tolerate electronic and navigational blow-outs, boats venturing away from it all should add single-function units, especially a dedicated GPS and a depth sounder. A set of paper charts for the voyage must be aboard.

Communication equipment should have the back-up of a handheld VHF and an all-frequencies receiver that can monitor weather forecasts on its own power. A back-up for wind instruments is acrylic yarn on the shrouds.

Next on the frequent failure scale are automatic bilge pumps. A pump will not kick on when its bilge sensor dies from wiring corrosion or when gunk from the bilge gums up its moving parts. Testing the sensor by hand at regular intervals will prevent a nasty surprise in an emergency. A sensor stuck in the “on” position causes endless cycling, eventually destroying the motor. Or, heat in the wiring of a continuously running pump will melt the insulation and short out the works, which can happen if the pump is protected with the wrong fuse (a frequent mistake) rated to fail at higher-than-recommended amperage. A proper back-up for any electrical bilge pump is a large-diaphragm pump made of bronze or very tough plastic. Aluminum pumps can develop poultice corrosion under flapper valves, disabling these models when you need them most.

The list of failures related to electrical systems runs on like a bad soap opera. Gel batteries tend to die suddenly and sooner than you expect. These batteries hate being overcharged, and boat-owners, in order to protect them, invest small fortunes in “intelligent” chargers that will coddle the gels. The trouble comes when the charger is deceived by failing circuits, loose connections, or bad cells in the battery. Overcooked, the gels die suddenly and permanently. Long-ranging yachts will do wisely to rely on lead/acid batteries charged via adjustable external regulators. The boat owner’s eye on the ammeter and voltmeter is the best means to healthy batteries.

Engine care

Auxiliary engines these days work ever-longer hours. When not propelling the boat they must turn refrigeration compressors and keep up a steady DC flow to electron-hungry devices like inverters and computerized electronic equipment. Clogged fuel filters will stop an engine dead. Even though you can pre-filter the fuel on its way to the tank you should also have a set of large filters between the tank and the injector pump. Place these for easy access so changing the filter elements is no hardship. A diesel engine will also refuse to run when air gets into the fuel system – a consequence of the fiddling with filters. Learn to purge the system and, best of all, install a small pump (away from the awkward priming pump on the engine), hand or electric, connected to a manifold with valves that allow applying small pressure in sequence – from filter housings to the injectors. Use this extra pump to pressurize and detect fuel system leaks in unexpected places such as hairline cracks in a filter housing.

Raw-water impellers on engines have limited life. An easy-to-service strainer inboard of the seawater seacock extends their performance. In addition, arrange good access to the raw-water pump cover so you can examine the rubber impeller blades regularly. Waiting until the engine overheats usually means that some of the impeller blades have already broken off – you will have to fish the pieces from the heat exchanger tubes and passages of the cooling system.

Running a modern ocean voyaging yacht takes work and attention, which, due to the increasing complexity of mechanical and electrical systems, tends to focus on the engine room. Because of this the rig and sails usually receive less attention. However, your boat’s rig needs regular attention too. A blow-up of the rig can have dire consequences.

Unlaminated Dacron sails commonly fall apart from long exposure to sunlight – UV radiation weakens the cloth and the stitching. Carry a good amount of adhesive-backed sailcloth to do temporary repairs at sea. The sail must be dry and cleaned (with alcohol or acetone) before applying the repair material. In desperation, some people used duct tape on both sides of a tear, and it holds for a while. However, you can detect imminent sailcloth failures before you leave dock. The first sign? Your white sail becomes yellowish along the foot. Make a crease there and try to tear the cloth by hand – if it rips, have the affected panels replaced and order a new sail. Too many voyaging sails disintegrate too soon due to the use of incorrect cloth. Insist on having your sails made of tightly woven cloth such as Marblehead, made by Bainbridge, and you can expect at least 10 years of service. Specify UV-protected brown thread. Order double stitching and wide overlaps of the panels so that, through the middle of the sail’s life, you can add a line of new stitching between the original stitches. Have the stitching coated with protective compounds like Duroseam. These measures will raise the cost by up to 50% but your sails should go on for 18 years instead of 18 months. Even in a quality sail the stitching remains vulnerable to chafe – caused by swinging lazy jacks and the flapping bunt of sail after reefing. On long trips keep the lazy jacks out of the way and use reefs points.

Rig failures

Aluminum masts today come with built-in internal channels for the mainsail slides – a source of frequent problems when using cylindrical plastic slugs. The plastic shrinks and wears out, and in a squall the whole sail suddenly blows out of the mast track. You should always have a full set of spare slugs or flat slides aboard. Both slugs and slides should have rounded corners to prevent jamming in the track. Aluminum masts finished with hard anodizing are much kinder on their slides, but painted masts will benefit from lubricants (Teflon or silicone) and frequent inspection. Webbing keeps the slides firmly attached to the sail until its stitching wears out – another detail to inspect. Since a yacht may lose its mainsail for a variety of reasons – UV damage, stitching failure, slides loss – carry aboard a trysail that, ideally, should have its own external track.

Losing a mast at sea surely hits 10 on the disaster scale. A mast stepped through the deck usually breaks at one of the spreader roots, leaving a good length of spar up there. If the boat carries a fixed-length, strong spinnaker pole, the crew, given a calm sea, should be able to extend the broken mast and fashion some kind of jury rig. Two spinnaker poles give you even greater flexibility.

Breaking a piece of standing rigging is the usual cause for dismasting, especially for a deck-stepped mast. However, a moderately tall, heavy-walled mast stepped through the deck will not fall over immediately after a single piece of wire gives out. An alert crew has a short time to change tacks in order to take the load off the weakened side. Exception is a super-high mast that in rough water will whip about so much that the first broken wire just begins a chain reaction. As usual, careful preparation is the best way to prevent dismasting. Here are the rigging elements to consider.

Standing rigging wire. The standard 302/304 stainless wire with swaged terminals has short life, especially in waters with high salinity. After the first two years of service, inspect the swages for hairline cracks and meathooks near swages. For voyaging, specify at least 316 stainless wire (more corrosion-resistant grades are also available) terminated by swageless fittings made of 316 alloy.

Turnbuckles. Stainless steel turnbuckles tend to crevice corrode in the threads hidden within the turnbuckle body and under the locking nuts. Specify open-body, forged-bronze turnbuckles and install cotter pins after the final tuning of the rig.

Toggles. Toggles between chainplates and turnbuckles ease the wrenching forces on the shrouds swinging on the lee side of the mast. Order forged load-rated toggles. Regularly inspect toggles under the furling gear on the headstay – they experience heavy side loading.

Spreaders. Isolate stainless steel spreader brackets from an aluminum mast – otherwise hidden corrosion will weaken the area. Normally spreaders should point slightly upwards, bisecting the angle of the shrouds they support so that the shroud, when loaded, does not tend to break the spreader against its fitting. Shroud wire should be firmly connected to the spreader tips with fittings or with stainless seizing wire.

Mast tangs. Tangs that consist of two thin stainless straps easily develop cracks – the perfect alignment of both parts on the clevis pin is vital.

Mast step. A neglected aluminum mast step stepped on a stainless base will corrode – and it will do so fast when seawater drips on it. Given time, the mast step will crumble, leading to suddenly slack rigging.

Breaking a boom may cause a serious rip in the mainsail and may get a crew hurt. The most common cause is a gooseneck fitting that does not allow the boom to pivot on its axis following the pull of the mainsheet. Most off-the-shelf goosenecks can only move sideways or up and down – any other movement imposes a wrenching load on them.

Plastic-coated lifelines that suddenly break are my pet gripe after going overboard once in an autumn Baltic gale and, years later, taking an unexpected dive into the Caribbean. The white plastic coating effectively hid corroded stainless wire inside. The widely used 302/304 stainless wire will rust through when starved for oxygen. For my own boat’s lifelines I use 316 alloy, 7 by 7, 3/16 inch wire, slipped it into an outdoor grade PVC water tubing and nicopressed at the ends – good for half a century or so.

Steering problems

Lately I have come across several cases of rudder and steering problems. On one boat new steering wires slipped off the quadrant – they should have been re-tightened after the initial load stretched them. Other boats had poorly installed pulleys leading the wire off the quadrant – a misalignment, possibly combined with the hull flexing in seaway, caused the wire to strand on the metal edges and part. On another yacht the wire stranded on the chain sprocket inside the binnacle – the installers forgot to test the job at dockside. All these failures were next to impossible to fix in rough sea conditions, and the boats’ owners resorted to emergency steering, which for some was hell to operate and was never tried beforehand.

The loss of a rudder a few hundred miles out will really challenge the crew. One crew saw theirs disappear after leaving Cape Town, South Africa, due to a Tobin bronze rudder stock corroding through. They made a textbook-perfect contraption out of a spinnaker pole and floorboards. Even though long-keeled and well-mannered, Crosstown Traffic, their 35-footer, put such a strain on the jury rudder that it fell to pieces. In the end they sailed to Namibia steering solely by sail trim. Going to windward without the rudder should not present much problem for a well-balanced boat with a reefed mainsail. Off-wind sailing will require a staysail trimmed on the centerline to keep the bow from rounding up – you need to experiment to find the right rig for the conditions.

Spade rudders are notorious for falling off, especially on older production boats. Builders used the cheapest materials for the assembly, which was hidden within layers of foam and covered with fiberglass. Even the best-made balanced spade rudders remain vulnerable because of the huge unsupported area. Their performance goes out of whack in rough conditions when the sea gets aerated near the surface. Adding end plates and a skeg ahead of the leading edge will improve effectiveness and strength of a spade rudder.

Autopilots come in all breeds, but a unit effective in semi-sheltered waters often fails on long ocean voyages. But short-handed yachts must have some way of self-steering. If a voyager doesn’t carry a windvane self-steerer, then a mechanical autopilot becomes a vital piece of equipment. Should it fail, a crew (typically a voyaging couple), exhausted by prolonged hand-steering in rough conditions may call for assistance or abandon ship. To avoid this, choose a proven model designed for a commercial fishing vessel twice the size of your yacht and provide plenty of electrical power to run it.

Or you may want to back up the complex with the simple. Corri and Willem Stein on the Dutch yacht Terra Nova have designed a successful set-up for a small autopilot. When the wind fails to blow and operate their Aries self-steerer, they can hook their autopilot onto the windvane base. Given the extra mechanical advantage, the autopilot can then steer their heavy-displacement Joshua ketch with little effort. As always, creative thought leads the way.

By Ocean Navigator