DieselShip's Online Content Library

Q1. Efficient smooth combustion depends upon some or all of the following: (16)

(a) A sufficiently high temperature to effect ignition

(b) A large delay period or ignition lag

(c) A minimum of after burning

(d) A large and rapid rate of pressure rise during the second stage of combustion

(e) Rapid heat losses to the walls Give the correct answer with adequate justification

Q2. (a) Write a letter to the company Technical Manager Stating with reasons, why the fuel bunkered in the last port is of very poor quality (10)

(b) Briefly describe the mitigatory measures that can be taken to reduce the impact of poor bunker quality (6)

Q3. (a) What are the different types of crankshaft used in marine diesel engines? (10)

(b) Discuss the various factors affecting the failure of crankshafts in marine diesel engine (6)

Q2. With reference to a 2- stroke slow speed main propulsion engine, sketch a line diagram showing the air starting system:

(a) State, with reasons, three safety features incorporated in an air starting system. (8)

(b) State with reason why an engine may fail to turnover on air (8)

Q5. Sketch and describe an independent two-stage air compressor. Draw a set of typical indicator diagrams and insert the various pressures and temperatures. Indicate the effect of a leaking HP suction valve and excessive HP clearance volume (16)

Q6.a) How does a modern 4-stroke medium speed marine diesel engine exhaust valve spindle rotate. (8)

b) What happens if the tappet clearance between the rocker arm tappet and the exhaust valve stem is too large. (8)

Q5. Sketch and describe a device employed for continuous monitoring of the viscosity of heavy fuel oil being supplied to a main engine (16)

Q8. (a) With the aid of a block diagram describe the operation of an electronic governor fitted to an auxiliary diesel engine (10)

(b) State the reasons for fitting a droop governor to a diesel generator (6)

Q9. Make a diagrammatic sketch of a jacket cooling water system as applied to a group of medium speed auxiliary diesel engine. Indicate the temperatures and pressures in the system. Describe in particular, the flow of water from entry to the engine, to the outlet from the engine and sketch the more important joints in the system (16)