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Q9. Describe in detail the causes and conditions that; A. Create an explosive atmosphere in a crankcase; B. Initiate a primary explosion. C.  Propagate a secondary explosion; State how hazardous conditions can be avoided.

Q1. With reference to torsional vibrations in a main propulsion installation based on medium speed engines, gearbox and controllable pitch propeller: Explain how the vibrations may be caused; State the possible effects and damage that could result; Discuss the methods employed to minimise the potential problems associate with torsional vibration; Describe how the natural vibration frequency of the system could be modified.

Q8. Describe the method of setting the safety valves of an exhaust gas boiler at sea. A. State the limits in terms of percentage above maximum design working pressure for setting safety valves. B. State the formality necessary when Chief engineer sets the safety valves

Q2. Explain EACH of the following; A. Effect of worn out main bearings on the condition of the crankshaft and propeller shaft system

B. The reliance on frictional grip in conventional built up crankshaft. C. The reasons for providing large fillets to oil holes in crankpins and journals

Q8. During the past 4 months since you have joined the ship as second engineer a number of main engine exhaust valves have suffered cracking and corrosion at the seating faces. Write a report to the superintendent covering the following points;

A. An explanation detailing how the problem became evident.

B. Your action upon recognising the extent and seriousness of the problem

C. Your reasoned views regarding the positive causes of the problem

D. Your recommendations to avoid future incidents.

Q4. Sketch and describe a common rail fuel system as fitted to a diesel engine. How is delivery of the fuel controlled?

Q6. A. Sketch and describe a flywheel that would be fitted to a large marine diesel engine; B. Show in the sketches how it is fitted and secured; C. What is the purpose of the flywheel? Recently some engine makers have considerably reduced the size of the flywheel. Explain how this can be done.

Q5. Sketch and describe an “out of phase” diagram for a large 2-stroke slow speed cycle engine. Describe in detail the part of the cycle showing the diagram. Using the diagram explain the effects of burning liable and low grade fuels (when fuel injection timing is not altered). Explain how good ignition and combustion can be obtained when using low grade fuel.