Lesson 2/Learning Event 2
FIGURE 48. POWER STROKE.
Just before the piston reaches the end of its compression stroke, fuel is injected into the compressed hot air.
This fuel ignites, and the piston starts down on its second stroke, the power stroke. Just as in the four-stroke-
cycle diesel, the expanding gases push down on the piston with great force. All compression-ignition engines
have long power strokes due to the slow and steady burning of diesel fuel.