DieselShip's Online Content Library

Q1. Explain how the following conditions affect the power developed by a diesel engine:

(a) Broken piston rings. (4)

(b) Worn fuel pump plungers. (4)

(c) Fouled turbochargers (4)

(d) Worn out liner (4)

Q2. Explain the advantages of fitting highly rated medium speed engines with double exhaust and air inlet valves (6)

(b) State the disadvantages of double valve arrangements (4)

(c) Explain the possible causes of persistent burning of exhaust valves if it is:

(i) General to most cylinders (3)

(ii) Specific to a single cylinder (3)

Q3. With reference to the diesel prime movers for generators in unmanned machinery spaces:

(a) Outline the monitoring and control equipment designed to protect the engine. (8)

(b) Describe the methods employed to test the monitoring and control equipment, during a routine check. (8)

Q4. (a) What are the causes of Turbocharger surging? How is it indicated to the watchkeeper? (8)

(b) What are the possible remedial action? (4)

(c) What are the reasons for excessive fouling of the turbocharger? (4)

Q5. Discuss the consequences of failure to maintain correct clearances in the case of auxiliary diesel engine crankshaft and bottom end bearing. Describe the procedure of taking crankshaft deflection (16)

Q6. Sketch and describe the operation of a crankcase oil mist detector. What operational maintenance does this instrument require for efficient performance. (16)

Q7. a) With the help of simple diagram, explain Variable Injection Timing (VIT). (8)

b) Explain with suitable diagram, start and end of VIT points. (4)

c) Explain with sketch variation of P(Max) with VIT position. (4)

Q8. (a) What do you understand by Specific Fuel Oil Consumption? Give some examples of SFOC for a two stroke engine and the auxiliary engines. (6)

(b) Explain the terms: (10)

(i) Flash point

(ii) Pour point

(iii) Calorific value

(iv) CCAI value

(v) Octane number and

(vi) Cetane number

Q9. Compare the desirable qualities of the lubricating oil selected for each of the following duties:

a) Auxiliary diesel engines. (4)

b) Stern tube bearings. (4)

c) Refrigeration compressors. (4)

d) Gear case of purifier. (4)

Give reasons for the differing properties of the oils recommended for these four purposes.