Question 132Motor Plants - Assistant Engineer70% to pass
The opening of an exhaust valve on a modern, large, low-speed, main propulsion diesel engine, may be actuated by_______________.
AI Explanation
The correct answer is C) hydraulic "push rods".
In modern, large, low-speed main propulsion diesel engines, the opening of the exhaust valves is typically actuated by hydraulic "push rods" rather than direct action of the overhead camshaft, compressed air pressure, or direct action of the main piston moving down. Hydraulic "push rods" provide a more precise and reliable method of valve actuation compared to the other options, which may not be suitable for the demands of a large, low-speed diesel engine.
The other answer choices are incorrect because: A) direct action of the overhead camshaft is more common in smaller, high-speed diesel engines; B) compressed air pressure is typically used for engine starting, not valve actuation; and D) direct action of the main piston moving down would not provide the precise control required for proper valve timing and opening.
Related Questions
#130 There are two glands provided where the piston rod exits the cylinder shown in the illustration. The purpose of the top gland is to_______________. Illustration MO-0083 #131 The diesel engine shown in the illustration, the exhaust manifold is indicated by the letter_______________. Illustration MO-0003 #133 The exhaust ports shown in the illustration are identified with the letter '_______________'. Illustration MO-0003 #134 The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by _______________.#135 The insertion of shims between the foot of a marine type connecting rod and a bearing box would result in_______________.