PRINCIPAL MOVING AND RELATED COMPONENTS

Many of the principal parts that are within the main structure of an engine are moving parts. These moving parts convert the thermal energy released by combustion in the cylinder to mechanical energy, which is then available for useful work at the crankshaft.

In this chapter we will discuss the moving and related parts that seal and compress gases in the cylinder and transmit the power developed in the cylinder to the crankshaft. Other parts that serve to develop and transmit power, such as timing gears and gear trains, are discussed in later chapters of this manual. After reading the information in this chapter, you should be able to recognize and describe the basic types, functions, and characteristics of valves, valve-actuating mechanisms, piston and rod assemblies, crankshafts, flywheels, and jacking gears.