A four stroke engine is an essential part of almost every automobile. A four stroke engine has many advantages. As an owner you should have a good understanding of the limitations of the engine that your vehicle has. In this article, we will discuss the limitations of a four stroke engine.
A four stroke engine has to undergo two full up and down revolutions consisting of four strokes between the top dead center (TDC) and bottom dead center (BDC) for a single power stroke. Whereas a two stroke engine can do this in a single revolution consisting of up and down strokes. Hence a four stroke engine generate less power than a two stroke engine. These are low RPM engines.
A four stroke engine consist of inlet and exhaust valves and lubricating oil chambers. All this makes the design of a four stroke engine complicated and intricate. This makes the troubleshooting and maintenance difficult. Comparatively, a two stroke engine has no valves and the lubricating oil is directly mixed with the fuel. This makes the design simple and easy to manufacture.
Large flywheel and bulky
Compared to a two stroke engine, a four stroke engine has a large flywheel and larger in size. Since power stroke is the third stroke in a complete set of two revolutions, a larger flywheel is required to store the energy and maintain a continuous operation of the engine. Hence, it is heavy and bulky and requires more floor area in the vehicle to accommodate itself.
Because of the bulky features, large size and intricately complex design of a four stroke engine, it is a little expensive at the beginning. The presence of inlet and exhaust valves, a heavy flywheel and a separate mechanism for lubricating oil etc. have to be accommodated in the engine. The manufacturing process becomes expensive for producing an engine with all these features. This makes four stroke engines expensive.
Although four stroke engines are facing all these limitations, the worth of the four stroke engines are not subdued. It carries immense benefits over two stroke engines. Four stroke engines have better torque even they produce less power. Little wear and tear results in long life. Complete fuel combustion leads to better thermal efficiency and fuel economy with cleaner and quieter operations. By virtue of all these attributes, four stroke engines are still surviving and most preferred for an automotive.