Question 185Motor Plants - Assistant Engineer70% to pass
A six-cylinder, four-stroke cycle diesel engine is fitted with a rotary distributor type air starting system. The speed of the rotating distributor disc is_______________.
AI Explanation
The correct answer is A) one-half engine speed.
In a rotary distributor type air starting system for a six-cylinder, four-stroke cycle diesel engine, the speed of the rotating distributor disc is one-half the engine speed. This is because the distributor disc needs to rotate once for every two revolutions of the engine crankshaft to properly time the air start pulses to each cylinder.
The other options are incorrect because B) the same as engine speed would not provide the proper timing, C) twice engine speed would be too fast, and D) four times engine speed would be excessively fast and not aligned with the engine's four-stroke cycle.
Related Questions
#183 Which of the following statements is true concerning the air starting valve, labeled "III", as shown in the illustration? Illustration MO-0046 #184 The pilot valves in an air pilot starting system for a two-stroke cycle, direct reversing, main propulsion diesel engine are operated by either a ported distributor disc or a/an_______________.#186 Starting systems for large, direct reversing, main propulsion diesel engines are usually_______________.#187 In a direct cylinder admission air starting system, once the engine begins to fire, the air starting check valve illustrated, is closed by_______________. Illustration MO-0107 #188 When an air started, four-stroke cycle diesel engine is being cranked over, the starting air is admitted to each cylinder during the beginning of its_______________.