DieselShip's Online Content Library

Q1. 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.

Q7. Make a report to the Chief Engineer of your vessel about malfunctioning of low lub oil pressure alarm for the auxiliary engine, observed during your watch, with special emphasis on the possible consequences. (16)

Q9. With reference to an auxiliary diesel engine:
(a) Explain how a crankcase explosion may occur (4)
(b) Identify the indications of poor combustion (4)

(c) State FOUR reasons for poor combustion (4)

(d) Describe the effects on engine condition and maintenance by allowing poor combustion to continue (4)

Q8. (a) Describe crank case Oil Mist Detector and the principle of its operation. (8)
(b) Draw crank case explosion relief door and name the parts. State pressure setting of the door. (8)

Q9. If an auxiliary diesel generator over speeds and runs away while off load, explain:

a) How it can be stopped? (6)

b) What is likely to be the reasons for the failure? (4)

c) Give details of what checks are made after the engine has been stopped, both regard to (6)

i) Mechanical checks and

ii) Electrical checks

Q6. a) In a 4-Stroke engine, describe each of the four strokes of the engine. (5)

b) Draw timing diagram of complete cycle (5)

c) How each stroke is completed, in the engine with action of crank travel and valves. (6)

Q7.a) What are the structural parts of 2-stroke main Engine? (6)

b) How are different structural parts held together? (4)

c) What is the function of Cross Head Guides.

(4)

Q8. a) Draw diagrammatic sectional view of crosshead of 2-Stroke Diesel engine. Name each part. (8)

b) Describe function of each parts. (4)

c) How concentric movement of piston rod is converted to angular movement of crankshaft. (4)

Q9. 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 graph variation of P(Max) with VIT position. (4)

Q2. (a) Describe in detail a four stroke cycle. Why it is called so? (5)

(b) Draw 4-Stroke engine cycle. With crank position of each stroke. (6)

(c) What is scavenging? Show the Scavenging step in the cycle diagram, what is its importance. (5)

Q3. Describe following terms with respect to Diesel Engine with suitable diagram:
(a) Natural aspiration (4)

(b) Scavenging (4)

(c) Supercharging (4)

(d) Types of Super charging in two stroke engine. (4)

Q3. With respect to Modern 2- Stroke Diesel Engine.

i) What is Electronically controlled engine? Which all functions of main engine are controlled electronically. (8)

ii) How these type of engines are superior to their earlier designs. (8)

Q4. Draw sectional diagram of the piston of 2-Stroke Diesel engine, marking each part. (8)

i) What is material of each part. (4)

ii) How many piston rings are in use, their type and material. (4)

Q5. i) Name different types of crank shaft by construction methods. (6)

ii) show different parts of Fully built Type Crankshaft and describe assembling process to complete the crankshaft. (6)

iii) What are materials used for each part. (4)

Q6. a) Sketch and describe a fuel oil system of a large diesel engine, from settling tanks to main engine fuel injectors. (10)

b) Also, comment on the importance of

i) Heating arrangement with temperature control. (3)

ii) Prevention of air lock in the system. (3)

Q7. What is specific fuel consumption of a diesel engine? Why is it necessary to specify it and how will you check this for the large diesel engine of your vessel. (16)

Q8. With reference to the construction of a turbocharger, sketch and describe

a) The rotor bearing and it's method of lubrication. (6)

b) Labyrinth seal and explain how such a seal work. (6)

c) Impeller and diffuser. (4)

Q9. Sketch and describe the operation of a crankcase oil mist detector. What operational maintenance does this instrument require for efficient performance. (16)