Question 35 AEL01 - Assistant Engineer - Limited

The Correct Answer is B **Explanation for why option B ("slow-speed engine fuel pump") is correct:** The component illustrated is a typical high-pressure reciprocating fuel pump utilized on large, slow-speed marine diesel engines (such as crosshead engines). Its primary function is to draw fuel oil from the booster system, increase its pressure drastically (often to 1,000 to 1,500 bar), and deliver a precisely metered quantity of fuel to the engine injectors at the correct timing for combustion. Key identifying features include the large housing, the main plunger mechanism, the delivery valve assembly, and the control rack or actuator used to adjust the fuel quantity (load control). **Explanation for why each of the other options is incorrect:** * **A) slow-speed engine cylinder liner lubricator:** This component is much smaller, designed to meter small, timed quantities of lubrication oil to the cylinder walls. It does not handle the bulk flow and ultra-high pressure required for fuel injection. * **C) centrifugal flyweight governor:** A governor uses rotating flyweights to detect engine speed variations and actuate control linkages to regulate fuel quantity. It is a control device, not a high-pressure, reciprocating pump mechanism like the one shown. * **D) injector cooling system pump:** This pump is typically a centrifugal or gear pump used to circulate coolant (water or dedicated oil) through the injector cooling jackets. It operates at relatively low pressure and does not possess the large, robust plunger and high-pressure delivery valve features characteristic of the main fuel pump.