**Right side of engine is the intake side, the left is the exhaust side**
1: Intake stroke. Vacuum created within cylinder pulls fuel mix into the combustion chamber.
2: Compression Stroke. Fuel mix is compressed by piston moving upward creating more potential energy within a smaller mix of fuel.
3: Power Stroke. Spark plug sparks causing the fuel mix to ignite forcing the piston downward.
4: Exhaust Stroke. Piston returns to the top of the engine pushing the exhaust gases out of the exhaust valve.
Things to note:
a. camshafts at the top of the engine, staying in time with the crankshaft, push the valves down on the appropriate stroke to allow transfer of gases.
b. 2 main parts of an engine are shown here: “Block”, bottom of the engine that houses the “rotating assembly” i.e. the piston, rod, and crankshaft. and the “Head”, top of the engine housing the valves, spark plug, and camshafts. The division can be seen at the bottom tips of the valves. (the thick horizontal line)