When does the intake event begin on a two-stroke diesel engine?

When does the intake event begin on a two-stroke diesel engine?

• A. At top dead center
• B. During compression
• C. After exhaust
• D. When the piston uncovers the intake ports

Answer: (D)

In a two-stroke diesel, there isn’t a separate intake stroke. The intake of fresh air starts the moment the piston uncovers the intake ports in the cylinder wall, allowing scavenging air to rush in and push out the exhaust. This downward motion opens the intake path, so air can fill the cylinder before compression and combustion. If the ports are still sealed (such as at or near top dead center), air cannot enter, so intake doesn’t begin. So, the intake event begins when the piston uncovers the intake ports.

In a two-stroke diesel, there isn’t a separate intake stroke. The intake of fresh air starts the moment the piston uncovers the intake ports in the cylinder wall, allowing scavenging air to rush in and push out the exhaust. This downward motion opens the intake path, so air can fill the cylinder before compression and combustion. If the ports are still sealed (such as at or near top dead center), air cannot enter, so intake doesn’t begin. So, the intake event begins when the piston uncovers the intake ports.