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Q7. What is meant by ‘Power balancing’ with respect to reciprocating engines? Why is balance desirable and how is it obtained in the case of a large marine engine? What difficulties may be experienced in balancing an engine running at about 500 R.P.M. and how can these difficulties be overcome?

Q2. a) Explain the term fuel ignition quality and indicate how a fuel’s chemical structure  Influences its value
b) State, with reasons, the possible consequences of operating an engine on a fuel with a lower ignition quality than that for which it is timed.
c) (i) Explain how an engine might be adjusted to burn fuel of different ignition quality.
(ii) State what checks can be carried out in order to determine that the engine is operating correctly.

Q5. Accidental grounding of the ship in which you are second engineer has occurred while on passage between ports.

a) Describe your immediate concerns as attempts are made to re-float the ship using the main engines (6)

b) Following failure to re-float and assuming operation on residual fuel at the time of the accident state your next priorities (5)

c) Describe any checks or inspection you Consider necessary before restarting the main engine after the ship has been re-floated (5)

Q4. With specific to reference to any make, sketch and describe the Cylinder Lubricating System used in new generation marine diesel engines. How will you effect the optimum cylinder oil feed with varying sulphur content of fuel oil. (16)

Q5. Slow steaming has become the standard operation mode for many ship operators. Discuss various technical issues connected ‘slow steaming’, with particular reference to: (16)

a) Crosshead bearing damage in T/C cutout mode.

b) Cylinder liner cold corrosion

c) Exhaust valve damages

Q6. a) Referring to ALCAP technology in marine purifiers, discuss with diagrams, how the Sludge monitoring system along with the Water monitoring system in modern centrifugal separator has increased the separation efficiency of oil? (8)

b) With respect to new development in de-sludging in separators, discuss the “Centri Shoot Discharge” system? (8)

Q9. With reference to crankshafts, explain EACH of the following:

A. The cause and effects of torsional vibration;

B. The term critical speed indicating why it can be a problem;

C. The term fatigue cracking and state, with reasons, TWO factors of crankshaft operation which have greatest influence on the likelihood of fatigue cracking

D. How a torsional vibration damper can reduce the effects of torsional vibration

Q1. With reference to a particular make of main propulsion unit, describe how the engine is reversed manually and discuss the problems involved and the safety precautions which would be required if the control were operated remote from the machinery space.

Q3. As second engineer you have been requested to obtain a set of indicator card from the large slow speed engine of a recently purchased second hand ship.

A. Describe your initial checks and preparations;

B. State with reason the types of card you would consider necessary and explain the procedure for obtaining these;

C. State in order of importance the additional information required with the card;

D. State your procedure for analysis of the cards and obtaining cylinder powers.