DieselShip's Online Content Library

Q1. (a) In reference to a Starting air system of main engine, explain the function of the air start distributor? (8)

(b) What should be the sequence of action to be initiated if the Automatic air starting valve malfunctions during manoeuvring? (8)

Q2. (a) Draw sectional diagram of main engine piston showing each part. Show cooling passages for oil cooled piston (12)

(b) Name the different materials used for the various components of the piston as indicated to the answer above. (4)

Q3. a) Explain, why is it important to measure bearing clearance in a diesel engine. (4)

b) What is Bridge gauge? How is the Bridge gauge used? Explain with a diagram. (6)

c) What are other recommended methods for checking bearing clearances. (6)

Q4. Describe following terms with respect to Diesel Engine with suitable diagram.

a) Piston Stroke (4)

b) Swept Volume (4)

c) Clearance volume (4)

d) Compression ratio. (4)

Q5. (a) What is a Exhaust Gas Economizer? Draw diagrammatic Sketch of Exhaust gas Economizer (EGE) naming each component (8)

(b) How is steam Generation controlled in Exhaust Gas Economizers? (4)

(c) Briefly describe procedure to maintain efficiency of such an E.G.E. (4)

Q6. If an auxiliary diesel generator over speeds while off load, explain:

(a) How can the engine be stopped? (6)

(b) What are the probable reasons for the failure? (4)

(c) Give details of the checks that are required to be made after the engine has been stopped, with regard to

(i) Mechanical checks and

(ii) Electrical checks (6)

Q7. (a) In a 4-Stroke engine, describe each of the different strokes of the cycle. (6)

(b) Draw 4-Stroke timing diagram describing the complete cycle.

Explain how each stroke is completed with action of crank travel and the inlet-exhaust valves. (10)

Q8. (a) With an aid of a sketch briefly describe the important structural parts of 2-Stroke main Engine? How are different structural parts held together? (10)

(b) What is the function of Cross Head Guides? (6)

Q9. For 2-Stroke Marine Diesel Engine

(a) What are the desirable properties of crankcase lubricating oil? (6)

(b) Why magnetic filter is fitted on LO system and where is it fitted? (4)

(c) Which property of synthetic lubricants allows them to perform better than mineral oils under heavy loads and elevated marine engine temperatures? (6)

Q4. (a) State the different types of turbo charger fitted in modern diesel engines (8)

(b) Describe the function of the (8)

(i) Nozzle ring

(ii) Labyrinth seals

(iii) Diffuser and

(iv) Inducer

Q9. Make a diagrammatic sketch of a jacket cooling water system as applied to a group of medium speed auxiliary diesel engines. Indicate the temperatures and pressures in the system. Describe in particular, the flow of water from entry to the engine, to the outlet from the engine and sketch the more important joints in the system (16)

Q1. The main requirements which a fuel injection system must fulfil are (16)

(a) Accurate metering of small amount of fuel oil

(b) Control of quality of fuel injection

(c) Proper timing of the fuel injection

(d) Selective distribution of the fuel in the combustion space

State whether each one of the points made above are true or false with reasons.

Q4. a) Describe what is nozzle burning of fuel Injectors and causes of nozzle burning on Marine Diesel engine. (6)

b) What investigations are required to find causes for nozzle burning? (6)

c) What actions are required to reduce the risk of Nozzle Burning? (4)

Q5. Efficient smooth combustion depends upon some or all of the following: (16)

(a) A sufficiently high temperature to effect ignition

(b) A large delay period or ignition lag

(c) A minimum of after burning

(d) A large and rapid rate of pressure rise during the second stage of combustion

(e) Rapid heat losses to the walls Give the correct answer with adequate justification

Q6. (a) Sketch and describe the Starting air system of main engine. (8)

(b) What are the safety interlocks provided in compressed air Starting system of Main Engine? (8)

Q7. Explain how sluggish action of the suction and delivery valves reduces the volumetric efficiency of an air compressor. (16)

Q8. 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. Sketch and describe a device employed for continuous monitoring of the viscosity of heavy fuel oil being supplied to a main engine (16)