reduce smoke Vauxhall There are cast in ducts from the crankcase
Historical design
Dugald Clerk developed the first two cycle engine in 1879. It used a separate cylinder which functioned as a pump in order to transfer the fuel mixture to the cylinder.6
In 1899 John Day simplified Clerk's design into the type of 2 cycle engine that is very widely used today.13 Day cycle engines are crankcase scavenged and port timed. The crankcase and the part of the cylinder below the exhaust port is used as a pump. The operation of the Day cycle engine begins when the crankshaft is turned so that the piston moves from BDC upward (toward the head) creating a vacuum in the crankcase/cylinder area. The carburetor then feeds the fuel mixture into the crankcase through a reed valve or a rotary disk valve (driven by the engine). There are cast in ducts from the crankcase to the port in the cylinder to provide for intake and another from the exhausst port to the exhaust pipe. The height of the port in relationship to the length of the cylinder is called the "port timing."
On the first upstroke of the engine there would be no fuel inducted into the cylinder as the crankcase was empty. On the downstroke the piston now compresses the fuel mix, which has lubricated the piston in the cylinder and the bearings due to the fuel mix having oil added to it. As the piston moves downward is first uncovers the exhaust, but on the first stroke there is no burnt fuel to exhaust. As the piston moves downward further, it uncovers the intake port which has a duct that runs to the crankcase. Since the fuel mix in the crankcase is under pressure the mix moves through the duct and into the cylinder.
Because there is no obstruction in the cylinder of the fuel to move directly out of the exhaust port prior to the piston rising far enough to close the port, early engines used a high domed piston to slow down the flow of fuel. Later the fuel was "resonated" back into the cylinder using an expansion chamber design. When the piston rose close to TDC a spark ignites the fuel. As the piston is driven downward with power it first uncovers the exhaust port where the burned fuel is expelled under high pressure and then the intake port where the process has been completed and will keep repeating.
Later engines used a type of porting devised by the Deutz company to improve performance. It was called the Schnurle Reverse Flow system. DKW licensed this design for all their motorcycles. Their DKW RT 125 was one of the first motor vehicles to achieve over 100 mpg as a result.14
Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
Automotive fraud network
Ads for the automotive industry are one of the most viewed by Internet users announcements relating to the exchange or purchase. The information contained in the notices contained in the virtual network often refer to many years of cars imported from abroad or after the accident. Of course, in most cases virtual proposal is only the form of information, and more content about our cars we need to look at the personal meeting. However, this does not discourage all sorts of scammers is the use of such trafficking on the Internet. Thus, by choosing Internet announcement on the interesting vehicles you need to be undoubtedly very vigilant for any kind of fraud.
Unruly car paint
One of the most common problems, which has to face many a owner of such a vehicle such as a car or a motorcycle, a scratch on the car paint. We can scratch the car in just a few moments, without using even this sharp tool. Many scratches formed, for example, the inability of parking or reversing. Unfortunately, many of them are also the result of actions of hooligans, we leave the car, for example, in the wrong neighborhood. How to deal with such a problem? Of course, in many cases it is necessary to visit the factory paint. In smaller straches it may be useful to also use, for example, with a special pen that allows at least a little to mask the resulting defects.