Two boats of the same length and age are most often told apart by their equipment. Stabilisers, a generator, air conditioning and bow and stern thrusters directly affect life aboard and handling. Each is also a system that needs maintenance. So in a listing the questions are what type each item is and what state it is in, as well as whether it is fitted.
Stabilisers and gyro stabilisers
Stabilisers reduce the boat's roll and make it more comfortable both under way and at anchor. There are two main types. In fin systems, fins extending from under the hull work against the roll. Their main effect is under way: it grows with speed and comes in without delay. Some versions also work when the boat is stopped. A gyro stabiliser relies on a heavy flywheel spinning fast inside the boat. It is effective at anchor and at low speed, usually draws its power from the generator and has to spin for a while before it reaches full effect.
On the pre-owned market, stabilisers are sought after. The points to check are the type, the service history and whether they were run on the sea trial. On a fin system, the fins and the places where they pass through the hull are seen with the boat ashore. On a gyro stabiliser, the service records show whether the maintenance laid down by the manufacturer was done on time.
The generator
When the boat is not on shore power, the generator feeds the air conditioning, the galley, the hot water and the stabilisers. Its capacity has to cover the boat's total load. Some boats have two, and if one fails the other goes on meeting the basic needs.
A generator is an engine in its own right. Its running hours, service records, cooling and exhaust are examined just like those of the main engines. The condition of its sound shield decides how quiet the nights at anchor are.
Some boats have a battery bank and an inverter in addition to the generator. At anchor overnight or on short stops, this feeds the lighting, the fridge and small appliances without the generator running. The age of the batteries and the charging arrangement show how useful the system really is.
Air conditioning
Marine air conditioning is mostly cooled by sea water. The sea-water pump, the strainers and the pipework need regular maintenance. In many systems each cabin has its own control, and some also heat, which makes the boat easier to use out of season. The air conditioning's demand has to be considered together with the generator. At a viewing, the unit in every cabin is run separately.
Bow and stern thrusters
Bow and stern thrusters push the boat sideways and make it easier to come alongside and to turn in a tight space. Bow thrusters are common. Used with a stern thruster, the boat can be moved bodily sideways. Electric ones are generally built for short bursts, and hydraulic ones can run for longer. On pod-drive boats, the joystick does a similar job.
Thrusters are judged by running them on the sea trial, and their tunnels and blades by looking at them with the boat ashore. On electric ones the batteries and the charging arrangement are checked too.
What to check in the listing and at the viewing
- Whether the listing states the type and capacity of each item
- The running hours of the generator and the stabilisers
- The dates of the last services, and the invoices
- Whether each system was run separately at the viewing and on the sea trial
- Whether the generator can carry the air conditioning and the stabilisers at the same time
- Whether there is an installation and service record for equipment added later
In the survey report, equipment is examined under the systems heading, and that is where it enters the overall assessment of the boat.
A boat with a long equipment list is valuable only if everything on the list works.
