Question 63Motor Plants - 1st Asst/Chief

The correct answer is D) The air starting valve is opened by cam action. The air starting valve labeled "III" in the illustration is typically part of the engine's starting system. When the engine is being started, the air starting valve is opened by cam action, allowing compressed air to flow into the engine's cylinders and facilitate the starting process. This is the normal operation of the air starting valve during engine startup. The other answer choices are incorrect because: A) The air starting valve is not held open by air pressure when starting, but rather by cam action. B) The air starting valve is closed when starting air is secured, not opened. C) The air starting valve does not open and close constantly during normal engine running, but rather is opened only during the starting process.