DieselShip's Online Content Library

Q1. With regard to care of lubricating oils onboard, answer the following:

(a)  Microbial degradation of lubricating oil and measures to prevent the same

(b)  Methods of ensuring correct sampling is done for the purpose of shore based testing.

(c)  If the shore based testing results show an abnormal values of water content and TBN for the crank case lub oil of a slow speed main engine, what will be interpretation and subsequent action?

Q2. A. Describe the procedure to be adopted for the inspection of a safety valve fitted to an exhaust gas fired auxiliary boiler stating, with reasons, which parts should receive particularly close attention.

B. Describe the procedure for the setting of safety valves of exhaust gas operated auxiliary boilers;

C. Explain the required action a watch-keeping engineer should take after the setting of safety valves as in (B)

Q6. With reference to hydraulic system for deck machinery identify: A. The types of contamination likely to be found in hydraulic systems for deck machinery; B. The sources of such impurities; C. Means used to prevent problems with contamination; D. Possible effects of the oil contamination on the system.

Q6. A. Sketch a Main Engine air starting system and describe how it operates. B. List the safety devices and interlocks incorporated in such a system and state the purpose of each

Q6. With reference to electro-hydraulic steering gears:

A. Explain in terms of control parlance, the function of the “Hunting gear”;

B. Explain the consequences if the standby pumping unit is motored;

C. State TWO methods employed to prevent the standby hydraulic pump being motored by the operating unit.

Q6. A. Explain how and why the performance of reciprocating air compressor tends to “fall off” in service. B. State how “fall off” is indicated and to what extent permissible before correction; C. Describe how optimum performance is restored; D. What is the significance of clearance volume: for reciprocating air compressors.

Q6.a) Define the cause and effect of thermal stressing in cylinder heads, liners, and pistons.

Explain why thermal stressing is aggravated with an increase in the cylinder bore.

Explain how stress concentration and it's effects is relieved by maintenance and operational practices.

Q8. A set of indicator diagrams including draw cards has been taken for a main diesel engine. Examine critically the following if the compression curve is normal - 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

Q9. With respect to Diesel Engines, describe the cause of - i. Piston rings that is too tight in the piston grooves; ii. Corrosion of piston rings; iii. Piston grooves that are worn; iv. Piston rings that is too slack with piston grooves. B. Describe the effect of each of the faults listed above and the remedial action for each.