The electrical system is different depending on the type of engine in the boat. For example, there are the internal combustion engine, and then a diesel engine.
Combustion engine
1) battery
2) starter motor
3) coil
4) ignition system
5) spark plug
6) cylinder for mixing air and gasoline
7) piston
8) piston rings
9) alternator
10) crankshaft
Diesel engine
1) battery
2) starter motor
3) diesel fuel injection pump
4) air cylinder
5) piston
6) injector
7) piston rings
8) alternator
9) crankshaft
Notes on operation – internal combustion engine
In outboard engines, the starter motor makes the engine start.
The starter motor is connected to the electrical system.
The coil transforms current from low to high voltage to light the spark plugs. Otherwise, a boat engine, as a function, is similar to a car engine.
Notes on operation – diesel engine
The electrical system of a diesel engine is easier than the previous one and therefore less prone to failure. Here the injection pump is connected to the crankshaft by belt and distributes incoming fuel from the fuel pump to the injectors (one for each cylinder).
In older diesel systems, even if the battery is disconnected, the engine continues to run.
Cooling
The cooling system is used to prevent overheating of any type of engine. The cooling element may be water or a specific product that is circulated under vacuum by means of a pump.
The overheated engine can seize and be damaged, even irreparably. The coolant or water circuit can be:
- A closed or indirect circuit: here first the circuit passes from the jacket, el compartment surrounding the combustion chamber. Then it proceeds into a special heat exchanger;
In other cases, the circuit may be open or direct.
In outboard engines the impeller pump is housed in the foot of the engine on the drive shaft. In outboard engines, on the other hand, the cooling water outlet jet is clearly visible. Water pumped from the outside directly cools the outside of the cylinders and thus the combustion chamber.
If we consider an open circuit, it is most important to monitor the constant leakage of water flecks from the exhaust duct. In inboard and inboard-outboard engines, the exhaust duct can be located in the live work to reduce noise emission.
Therefore, you should periodically inspect the intake that may build up from algae or plastic fragments.
In outboard engines, it should especially be checked that the intake grille remains submerged to avoid damage to the impeller.