reduce smoke BMW In 2-stroke crankcase scavenged engines
In 2-stroke crankcase scavenged engines, the interior of the crankcase, and therefore the crankshaft, connecting rod and bottom of the pistons are sprayed by the 2-stroke oil in the air-fuel-oil mixture which is then burned along with the fuel. The valve train may be contained in a compartment flooded with lubricant so that no oil pump is required.
In a splash lubrication system no oil pump is used. Instead the crankshaft dips into the oil in the sump and due to its high speed, it splashes the crankshaft, connecting rods and bottom of the pistons. The connecting rod big end caps may have an attached scoop to enhance this effect. The valve train may also be sealed in a flooded compartment, or open to the crankshaft in a way that it receives splashed oil and allows it to drain back to the sump. Splash lubrication is common for small 4-stroke engines.
In a forced (also called pressurized) lubrication system, lubrication is accomplished in a closed loop which carries motor oil to the surfaces serviced by the system and then returns the oil to a reservoir. The auxiliary equipment of an engine is typically not serviced by this loop; for instance, an alternator may use ball bearings sealed with its lubricant. The reservoir for the oil is usually the sump, and when this is the case, it is called a wet sump system. When there is a different oil reservoir the crankcase still catches it, but it is continuously drained by a dedicated pump; this is called a dry sump system.
Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
Most truck and automotive diesel engines
Diesel cycle
Main article: Diesel cycle
P-v Diagram for the Ideal Diesel cycle. The cycle follows the numbers 1?4 in clockwise direction.
Most truck and automotive diesel engines use a cycle reminiscent of a four-stroke cycle, but with a compression heating ignition system, rather than needing a separate ignition system. This variation is called the diesel cycle. In the diesel cycle, diesel fuel is injected directly into the cylinder so that combustion occurs at constant pressure, as the piston moves.
Otto cycle: Otto cycle is the typical cycle for most of the cars internal combustion engines, that work using gasoline as a fuel. Otto cycle is exactly the same one that was described for the four-stroke engine. It consists of the same four major steps: Intake, compression, ignition and exhaust.
PV diagram for Otto cycle On the PV-diagram, 1?2: Intake: suction stroke 2?3: Isentropic Compression stroke 3?4: Heat addition stroke 4?5: Exhaust stroke (Isentropic expansion) 5?2: Heat rejection The distance between points 1?2 is the stroke of the engine. By dividing V2/V1, we get: r, where r is called the compression ratio of the engine.
Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
Please note that when you buy a foreign car!
Acquisition of foreign used cars from Germany or France is very popular. When buying a car from abroad we have to be careful if the seller does not deceive us, because there is no shortage of vehicles which, for example, have accidents and are sold as accident-free. Then the car can really be in bad shape, although aesthetically looks good and inconvenience are covered. This creates a really big risk and it is worth to choose the service of your friends in this regard. Imports of cars from abroad is often a way to earn a certain amount of money, so a lot of people lead such activities. So let's go to a friend or a person with a command when you plan to buy this car.