Final answer:
A flathead engine has both the intake and exhaust valves in the block, which is different from modern overhead valve designs. It operates using a four-stroke cycle consisting of the intake, compression, power, and exhaust strokes.
Step-by-step explanation:
The type of engine where both the intake and exhaust valves are located in the block is known as a flathead engine or side valve engine. In a flathead engine, the valves are placed in the engine block next to the piston, rather than in the cylinder head, as found in modern overhead valve and overhead cam engines. The description of the internal combustion engine process, particularly the four-stroke cycle, provides insight into how an engine operates. This includes the intake stroke, compression stroke, power stroke, and exhaust stroke, all contributing to the conversion of fuel into mechanical energy. Specifically, the exhaust stroke expels the hot gases to make way for a new air-fuel mixture to start the next cycle.