The reason why you float in water when laying down with your back to it is because of buoyancy. This is the same principle by which boats large and small are able to float through water and cover vast distances no matter how heavy they are.
Archimedes is the inventor of this principle and it's mainly because of him that we were able to travel 70% of earth's surface since it's how much it's made of water. Thanks to their hull, boats are able to be pushed away by some of the largest engines on the planet no matter how much steel went into making the vessel. Others are much smaller and don't necessarily have the engine in the hull.
Parts of a Marine Fuel System
Fuel Lines
A system of only a handful of important components that work together with the engine is the fuel system. What connects all these components together are the fuel lines which are not exactly the same as those found in your vehicle or motorcycle. Proper marine fuel lines are made to withstand the rigours of the sea which can easily make them wear out before any major service happens.
Tank
The fuel comes from the fuel tank and it's where it's stored until your engine needs some of it. The fuel system of a boat is similar to that in your vehicle when it comes to transporting that fuel to the engine but before it gets to it, it needs to go through some quality control.
Filter
The quality control in this case is a fuel filter. The filter rids the fuel of any particles that can cause damage or misfiring and thus keeps the engine in good shape. That's why it's important to replace it on time as otherwise you run the risk of clogging it or even worse shortening the lifespan of the engine.
Pump
What helps move the fuel from the tank to the engine is the fuel pump. Today's pumps are mainly electric but they can also be mechanical which makes them a more reliable solution but not as efficient.
Injector/ Carburettor
The earliest marine engines made use of carburettors to supply the fuel to the combustion chambers which today is a dated technology as the majority rely on injectors. Fuel injectors are more efficient than carburettors and also smaller. Keep in mind that fuel injectors are more expensive when it comes to repairs.
Sizing Fuel Lines
Diameter
You can't just get any type of marine fuel lines and expect them to work with your boat's fuel system. The size or diameter of the fuel lines you go for depends on the engine's displacement too. Larger displacement engines require larger diameter lines as more fuel needs to be supplied due to the larger capacity combustion chambers. This is especially the case if your boat makes use of a carburettor. You can start as low as 6 mm and go as large as 15 mm but make sure to refer to the manufacturer's recommended fuel line sizes for this.
Pressure
The pressure in fuel lines for boats is as important as the amount of fuel they transfer. The higher the pressure in a boat fuel line the quicker the fuel is able to pass through but that shouldn't be a determining factor when it comes to improving efficiency. Although it does affect this aspect, it can also be a bad thing when it comes to temperature changes. Smaller diameter fuel lines for boats can definitely increase pressure but they won't necessarily make for as efficient of a fuel delivery.
Power
This is where you need to take into account the power of the engine. The more HP it produces the quicker the fuel delivery needs to be but at the same time the more fuel it needs at a more frequent rate. Sometimes lowering the pressure in the lines can lead to a more efficient system as long as the delivery itself is more frequent and not cut off. Changing the diameter of the lines can affect this but know that the pressure-to-flow rate is not going to deliver the same results for every engine.
Benefits of Rubber Fuel Lines
Corrosion
While flexible metal lines do exist they are not as versatile as rubber ones as the latter is not affected by corrosion. You just can't get rubber fuel lines for boats to corrode no matter what you try. While you may puncture them more easily they are still a more fitting solution, especially in tight spaces.
Flexible
One of the main advantages of rubber fuel lines is their alleged downside, their malleability. This is, in fact, what makes them superior to their rigid counterparts. The flexibility of rubber lines is something you don't get with any other material and that's what makes them ideal in almost any condition.
Durable
Being malleable doesn't mean being a temporary solution as rubber lines are quite durable. They can perish like any other type of boat fuel line but they are not as easy to give in to the rigors of the sea.
