Updated: Feb 15, 2022
In marine applications, engines and systems show some differences from land vehicles. We can roughly list them as follows:
1 - The engine generally used in sailing boats is diesel engine. These engines, which work with the principle of internal combustion, have much lower rpm and higher torque than the gasoline ones. Gasoline engines are not preferred because of the potential danger of gasoline and steam in closed interior spaces in sailing boats. Gasoline engines are generally used in outboard engines or some motor yachts.
2 - Engines in marine use are generally equipped with seawater cooling systems. The place of air in the cooling system on land, sea water; The ventilator has been replaced by an impeller and the radiator by a cooler.
3 - The power transmitted to the wheels on land is transferred to the propeller at sea. A shaft rotating on an axis moves in some sleeve or bearing. In S-drive systems, there is no shaft. The shaft coming out of the engine is transmitted to the propeller by means of a gear group. The rubber mounts that connect the engine with the hull and are not affected by vibration are called engine mounts.
4 - In general, the engine room in sailboats is quite small. For this reason, relatively small machines are used in terms of size compared to land vehicles. Similarly, especially in sailboats, since speed and lightness are parallel, many motor blocks are produced much lighter than their counterparts on land.
5 - As in all other motor vehicles, it charges the batteries over the alternator as the engine runs. However, especially sailing boats use larger battery packs to meet the ongoing electricity consumption. Often a separate engine group is formed to start the engine and a service group is formed and separated from each other to meet daily use.
6 - How much the boat engines are worn out is evaluated by looking at the usage time instead of the kilometer clock as in land vehicles. Likewise, engine size is spoken over horsepower (HP) instead of engine volume as in car engines.
Despite all these differences, whether it is land application or marine, the working principle of diesel engines is generally the same.