Broken car - some solutions

Dodane: 23-08-2016 13:07
Broken car - some solutions oil for Great Wall

The top dead center

4-stroke engines
Main article: 4-stroke engine
Diagram showing the operation of a 4-stroke SI engine. Labels:
1 ? Induction
2 ? Compression
3 ? Power
4 ? Exhaust

The top dead center (TDC) of a piston is the position where it is nearest to the valves; bottom dead center (BDC) is the opposite position where it is furthest from them. A stroke is the movement of a piston from TDC to BDC or vice versa together with the associated process. While an engine is in operation the crankshaft rotates continuously at a nearly constant speed. In a 4-stroke ICE each piston experiences 2 strokes per crankshaft revolution in the following order. Starting the description at TDC, these are:78


In a splash lubrication system

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.


Winnings in contests - why they are often associated with the automotive industry?

We can easily notice that the cars or motorcycles are very often one of the main prizes in various competitions or sweepstakes. Why is it like that ? Well, these machines are often very valuable and can significantly make life easier for the winner. So valuable prize is designed to encourage more participants to take part in the common play or boot from the competition. It is a very proven grip, which for years makes competitions with prizes automotive enjoyed considerable popularity. Admittedly, win a car or a motorcycle or any other vehicle is also associated with considerable charges, which obliges us right relating to competitions; not discouraged, however, many taking part in all kinds of lotteries.