As a potential buyer of a preloved boat, the importance of conducting a sea trial on your dream craft cannot be understated. It may be the most important aspect of your decision making.
A sea trial is a critical part of the buying process, and if professionally conducted it will provide substantial information on whether the purchase can go ahead or to “steer away” from the particular yacht. There is no other way to know if yacht engine is looked
It is not uncommon for sellers, and brokers to offer a vessel for sea trials with the presence of the Yacht’s main engine OEM representative on board to conduct what is known as an engine diagnostic test. But it must be borne in mind that results thus obtained are generally technically profound to decipher and usually, a set of operating parameters by way of numbers that does not paint a clear picture on the other important aspects of the particular vessels characteristics, in particular her turning circle, stopping distance & actual yacht handling.
This is where engagement of a professional and independent Yacht surveyors come to the fore. (theyachtsurveyors.com)
Besides the technical jargon that would generally emerge from the OEM diagnostic tools, aspects such as the structural elements of the hull, deck and overall construction, as well as highlight any faults within the boat's electronics and its operating systems. In addition to engines, and their cooling, an exhaust system, such as steering system, running gear and most of the installed equipment, can only be determined by the presence of an experienced engineer surveyor overseeing the sea trial process. A yacht skipper who is well versed with this, if also comes handy.
A sea trial is thus a perfect opportunity to feel
how the vessel operates at cruising speed, check for
vibrations, practice hard turns, and experience riding
in rough waters.
For new buyers, it is not always clear what they are looking for, and this is where Constellation Marine surveyors can step in and assist in highlighting various aspects that are considered worthy of the buyer’s attention.
In essence, we at Constellation Marine Services will enable testing of the boat in a way that you plan to use the boat.
The yacht surveyor’s engagement will commence much
before she hits the open waters, starting from preparations
– that enable us to come as close to replicating ideal
“real world scenarios” of a typical
day on the water, such as the weight of supplies, guests,
and possibly crew and much of others that can significantly
impact performance of the boat that is to be tested.
If the boat is preloved, it is imperative that the fitted electronics on board are pre-checked, not only for them being powered up, but also for their screen visibility. Their software versions fitted to navigation instruments and the general ergonomics of the control and maneuvering systems placed at the helm station/s
The yacht surveyor will then ensure, to the extent possible, that the boat is fully commissioned, and that all equipment applicable are on board, charged and operational.
Even prior to starting the engines, and if the design
permits, the yacht surveyor from Constellation Marine
Services will encourage operating the throttle and shift
controls to confirm smooth, easy operation and positive
mechanical detents, primarily associated with pneumatic
or hydraulic locks within the operating system.
Ideally, the trials will begin with cold engines, as cold starting may reveal conditions that may be unnoticed when the engines are already warmed up, such as starter issues and signs of faulty ignition and fuel supply systems.
Should the boat have multiple engines, it is prudent to start and operate each engine on idle separately, this provides a good indication on issues associated with each engine when running isolated.
During this time of idle running, the yacht surveyor
from Constellation Marine Services, will test the charging
systems, by applying a load on to the power supply units
by switching on lighting, blowers, refrigerators, air
conditioning units etc, to report if the alternator
is supplying enough current to satisfy the load requirement.
The yacht surveyor from Constellation Marine Services will then check the level of water or water mixture in the bottom bilges, and try and look for signs of oil, fuel or coolant leakages.
Heading out to open waters, it is prudent to have
a visual look at the exhaust emissions during slow speed
running, to determine its color which is indicative
of improper fuel ignition or lubricant leakages.
In order to evaluate the overall handling characteristics, we will put the engines through a range of RPM and speeds, in different conditions, such as head and following seas, beam seas, to observe that power delivery is smooth and predictable.
In general, it is expected that in seaway, the boat will track straight at cruising speeds, when both (if twin) engines set to the same RPM. Not doing so is an indication of steering misalignment and indication of excessive steering needed to be applied to maintain course.
At cruising speeds, the yacht surveyor from Constellation
Marine Services, will then retract the trim tabs to
observe any issues with the boats natural trim, and
then open each side trim tab individually, to observe
change in hull trim and heading. Ideally the response
should be gradual and largely predictable.
Approaching high speeds, we will observe the bow rise as the boat approaches its plane, and the associated visibility. At this time, we will also closely watch the main engine acceleration once the throttles are fully opened, if the main engines accelerate rapidly, it is an indication of propeller slip which will be required to be investigated.
We will then bring up the engines to its upper end (without exceeding the manufacturers limits) and temperature scan the heat exchangers, oil coolers, exhaust risers and manifolds for temperature anomalies. It is recommended that the engines be run at the upper limits for no more than 2 to 3 minutes.
At this time, we will quickly run to the interiors
to check for vibrations, open doors, cabinets and fixtures
to check for more than normal binding or looseness.
We understand all hulls flex when in seaway, but excessive
clearances between panels may be an indication of abnormal
We will then take a look on how comfortable the interiors were during the high speed trials, from a point of view of noise and smell, it is not uncommon for inboard engine exhaust leaks to percolate within the living spaces and this may lead to general unpleasantness if not detected and fixed.
The surveyor will then perform a steering test, ideally traffic permitting, by a hard-over turn to each side. Ideally, the boat should carve cleanly and powerfully through the turn without the engine struggling to maintain speed or the propeller losing its bite on the water.
Post completion of the sea trial, a complete visual inspection of the inboard engine room compartment will be made, once again to indicate visual signs of leaks, and generally a sample of the lubricating oil will be collected, once the engines are cooled down to a temperature for us to be possible to do so.
In conclusion, we as Constellation Marine Services, urge potential buyers to have sea trials conducted with the presence of experienced surveyors from Constellation marine, and not solely rely on the diagnostic reading from OEM representatives, as this will never provide a holistic condition of the boat during its use.