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Q1. As Chief Engineer Officer, write a report to the engineering superintendent regarding failure of a four-stroke main engine to complete a slow turning procedure and the discovery of water around a cylinder head gasket after the failed slow turning attempt. The report must outline possible causes of the problem and the steps taken to identify the exact cause. The report must also explain the measures taken to rectify the defect(s) and the steps taken to prevent similar future incidents. (16)

Q2. With reference to main engine crankcase explosions:

a. Explain the cycle of events leading to a secondary crankcase explosion; (6)

b. As Chief Engineer, explain how an engine system should be managed in order to minimise the risk of a crankcase explosion and the effects of a crankcase explosion should one occur. (10)

Q3. (a) Explain why a diesel engine cylinder is supplied with excess air. (4)

(b) Explain why fuel droplet size produced during injection has to be within narrow limits in order to enable good cylinder combustion to be achieved. (4)

(c) Explain how the desired fuel droplet size is produced by fuel injectors. (4)

(d) State why fuel injection timing has to be within narrow limits to enable economic engine operation without bearing overload. (4)

Q3. With reference to a Closed Loop engine exhaust gas SOX scrubber system:

a. Describe, with the aid of a sketch, such a system; (8)

b. State, with reasons, the fluid which is used for SOX scrubbing in this system; (4)

c. State how the effectiveness of the scrubbing fluid is maintained and how the sludge is removed and disposed of. (4)

Q5. (a) Describe with the aid of sketches, the procedure for lifting a cylinder cover from a slow speed crosshead engine, explaining how the lifting gear is attached to the cover. (6)

(b) State the risks that may be associated with lifting a cylinder cover using the procedure described in part (a). (4)

(c) Describe the arrangements which must be in place to ensure that all lifting equipment has a current test certificate and is fit for operation. (6)

Q6. With reference to medium speed auxiliary diesel engines:

(a) explain why twin air inlet and exhaust valves are often fitted to each cylinder head; (6)

(b) explain why, in some cases, valve rotation is employed. (4)

Q6. With reference to two stroke, slow speed engines:

Explain what is meant by the term thermal stress and how this can cause cracking of the crown surfaces; (4)

Sketch a cross section of a piston, labelling the MAIN components and indicating coolant flow; (8)

State a cause of EACH of the following defects:

(i) Burning of the crown upper surfaces; (2)         (ii) Carbon deposits in the cooling spaces. (2)

Q5. (a) Describe, with the aid of a sketch, the arrangement of the gas and liquid fuel systems at the cylinder of a dual fuel 4-stroke engine, stating the input and output signals at the controller. (12)

(b) Describe the arrangement of the gas fuel piping system used for a 4-stroke dual fuel engine, stating the safety features incorporated. (4)

Q8. Write a report to the engineering superintendent regarding the failure at sea of a crosshead main engine bottom end bearing. The report must explain how the defect was detected, the immediate action taken to prevent further engine damage, the subsequent action taken to ensure that the vessel was able to continue on passage to the next port, probable cause of the bearing failure and other checks made on the engine. (16)

Q4. With reference to medium speed diesel engine cylinder liners:

a. Explain the cause and effects of polishing and glazing; (6)

b. Explain the action of an anti-polishing ring during the operation of the engine; (5)

c. Describe how effective cylinder lubrication is achieved. (5)