For that matter, when you start your vehicle with a cold engine is called a cold start since it creates exactly this problem that requires rich mixture to overcome. That said, you can easily understand that the colder the gasoline, the lower its vaporization rate will be. However, if you place it fast inside the bowl, it will quench the fire of the match.
You can do a simple experiment to see this working, take a small bowl filled gasoline and place a lighted match close to its vaporizing surface, it will fire up the vaporizing gas.
In order to have ignition you must have gasoline that vaporizes in a good rate. Before explaining this you should be aware that gasoline (liquid form) is not exactly flammable, its vapor is. I’m fairly sure that by know you should be wondering what’s with that “choke plate” at the very entrance of air in the carb’s body. Since the delivered mixture should not be the same for all engines, carb’s provide some simple screws (look at the given picture for speed and mixture screws) that can be used to adjust the fuel jet and butterfly valve to provide the best possible mixture. The more you push the accelerator, the more that valve opens delivering more air/fuel mixture to the engine. This is commonly connected through a line to the accelerator pedal or lever depending on the vehicle. Now, you can see a butterfly valve named throttle plate. What it happens is that it moves to an adjustable tiny hole that let’s it flow inside the main body of the carb. In the figure I gave it is not very clear what happens to the fuel after it enters the float bowl. Now that you hopefully have a better picture of the whole thing, let’s jump back to the carb’s operation. In this picture, apart from the carb you can also see the air filter/cleaner as well as its cover, a small pipe that is used to distribute the output mixture of carb to the two cylinders of the V-Twin engine (known as intake manifold) and all the gaskets, clamps, extra fuel lines and screws required to mount this kit. – If carb has air filter/cleaner, it passes through itīefore moving on, here is a real carb kit for V-Twin engines designed by S&S that will hopefully help you apply the above diagram information to a more realistic case.
On the other hand, the air has an even simpler path, which is: – At last, gas enters the float bowl of the carb – The fuel line drives the fuel to the fuel filter – The fuel pump inside the gas tank pumps gas when the starter begins Now, looking from right to left in the above figure we have the following two paths for each of the mixture’s elements… Its design is straightforward as you can see in the figure below. Although it is very rarely used in modern vehicles it was the most common type used until the early 90s in both cars and bikes. This is the “old school” type for getting the air/fuel mixture into the combustion chambers. Although, my posts focus mainly on gasoline engines, the below information applies to diesel ones too. That said, you should have some very basic knowledge of this type of engines to understand this blog post. Hello again fellows, in this post I will attempt to provide an overview of the most widely used techniques for fuel management systems in internal combustion engines.