DieselShip's Online Content Library

Q1. You have been appointed as Second Engineer to a new vessel that experiences severe aft end vibration. The problem is thought to emanate from the propeller. Describe the cause of vibration and suggest possible remedies including the selection of a new propeller with a different number of blades.

Q7. With reference to medium speed engine cylinder liners:

A. Explain the cause and effects of Polishing or glazing;

B. Describe, with the aid of sketches, an anti-polishing ring and how it is fitted in the liner;

C. Explain the action of anti-polishing ring during the operation of the engine.

Q3. Discuss critically the following alternative types of main propelling machinery for installation in a proposed new ship - A. 2 stroke single acting cross head type slow speed engine; B. 4 stroke single–acting with reverses / reduction gear.

Q7. With reference to the 4-stroke medium speed engines:

A. Define the cause and effect of thermal stressing in cylinder Heads, liners and pistons.

B. Explain why thermal stressing are aggravated with increase in cylinder bore.

C. Explain how stress concentration and its effects are relieved by maintenance and operational practices.

Q4. A. Briefly describe the causes and effects of bacterial attack of lubricating oil.

B. Bacterial activity has been detected in the lubricating oil of the main engine fitted in the ship aboard which you are serving as 2ndeng. Write a letter to the owner/operator of the ship indicating the action you intent to take and offer suggestion to the avoidance of future incidents.

Q8. (A) A set of indicator diagrams including draw cards has been taken for a main diesel engine, noted that compression curve is normal. Examine critically and give reasons for following observations.

i. The maximum pressure is lower;

ii. The maximum pressure is higher;

iii. The expansion curve is lower;

iv. The expansion curve is higher.

(B). Describe how the faults as mentioned above can be rectified

Q7. With reference to auxiliary diesel engines, suggest probable causes that would create EACH of the following conditions and state how they would be rectified: A. Knocking; B. Loss of power; C, Loss of lubricating oil pressure

Q3. With reference to large starting air receivers: A. Explain where corrosion is likely to occur and state why it occurs in these regions: B. State the how the incidence of corrosion in air receivers might be minimized; C. If serious corrosion is detected in a starting air receiver and that receiver must be used explain how you, as Second Engineer, would determine the maximum pressure to which the receiver should be subjected; D. State the further action a Chief engineer must take upon discovering such air receiver corrosion.

Q9. With reference to diesel engines fitted on board ships, discuss A. Sludge formation in lubricating oil systems, B. Role of additives in lubricating oils, C. Steps taken to ensure that treated oils are maintained in their optimum condition, D. Adverse effects on bearing metal due to incompatibility of lubricating oil.