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Q4. Discuss the validity of EACH of the following statements with respect to large slow speed diesel engines: A. Bearing clearances obtained by taking leads (or use of plastic inserts) are fundamentally more accurate than those obtained with the use of feelers;

B. Bearing wear down can be measured by taking deflections; C. A timing chain should be renewed when its slackness causes late fuel injection and exhaust valve operation; D. Timing chain slackness is solely due to stretch of the link plates.

Q7. A. Explain in detail how an in-water survey is carried out; B.  State the requirements to be fulfilled before an in-water survey is acceptable to the survey authority; C. Construct a list of the items in order of importance that the underwater survey authority should include.

Q5. With reference to main air turbochargers:

a) Give a reason why binding wire is frequently fitted near the top of the blades

b) Mention one fault that occasionally develops with binding wire in services,

c) Define the cause and identification under running conditions of turbine blade damage

d) State how (c) can be largely avoided.

Q4:  Comment on the reliability and maintenance requirements of two of the following;

(i) Pneumatic control equipment,

(ii) Electro-mechanical control equipment,

(iii) Electronic control equipment

(b) Discuss the routine attention required and the defects, which may occur in service.

Q6.(a) Suggest four reasons why the temperature of the oil in the steering gear system may  become excessive.

(b) With reference to steering gears explain how the ship may be steered in each of the following circumstances;

(i) destruction by fire of the primary supply cable;

(ii) destruction by fire of the telemotor lines;

(iii) bearing failure in the running pump;

Q1. A). Describe the procedure for opening a bottom end bearing for inspection making reference to the positioning of the crank and the safety precautions to be observed.

B). State how the bearing clearance may be checked and adjusted when necessary

C). State TWO defects, which may be encountered during inspection of the bottom end bearing and crankpin giving possible causes of EACH.

D). State TWO checks, which should be made before returning the engine to service following overhaul of the bottom end bearing.

Q7. An Auxiliary boiler is periodically unattended and equipped with alarms to cover low water level, high steam pressure, and air and flame failure.

A. State why and how fuel the burners are automatically cut off under alarm conditions of water level, steam pressure, air and flame failure.

B. Describe how and when each of the above alarms is tested without endangering the boiler.

Q8. a) Describe the inspection, which is required to be carried out in the dry-dock after the stern of a ship has heavily struck a dock wall. (8)

b) The propeller is found to be damaged, and it is decided to fit the spare propeller. Describe the process and mention the precautions to be taken to ensure correct assembly. (8)

Q9. a) State why onboard testing of fuel oil whilst taking bunkers can be advantageous. (4)

b) State how a representative fuel sample may be obtained during the bunkering operation. (4)

c) Explain how EACH of the following is formed during the combustion of fuel: - (4)

(i) Oxides of Nitrogen, NOx (ii) Carbon Monoxide, CO (iii) Oxides of Sulphur, SOx

d) State how the effects of sulphurous products of combustion on the engine system may be reduced.