78/89/EKM-2
Sr. No.
EXAMINATION OF MARINE ENGINEER OFFICER
ENGINEERING KNOWLEDGE
(MOTOR)
CLASS II
(Time allowed - 3 hours)
Motor Candidates
June 1999
Afternoon Paper Total
Marks 100
N.B. - (1) Do not deface or make any mark on this paper.
(2) Attempt SIX questions ONLY.
(3) All questions carry equal marks.
(4) Marks for each part question are shown in brackets.
(5) Neatness in handwriting and clarity in expression carries weightage
1. With reference to fuel and safety:
(a) Explain the meaning of the term closed flash point and indicate how it is obtained ; (4)
(b) State the reasons for the minimum closed flash point stipulation for fuel in storage and give the permitted
figures; (3)
(c) State the meaning of the term self ignition temperature; (3)
(d) State, with reasons, the safety device fitted to fuel storage tank vent and sounding pipes and indicate
precautions that should be taken to ensure that these device function correctly. (6)
2. With reference to main engine camshaft chain drives:
(a) Explain the term chain stretch and state its causes; (4)
(b) Explain the effect of chain stretch upon engine operation; (4)
(c) Describe the engine adjustments required in order to counteract the effects of chain stretch; (4)
(d) Describe the procedure for replacing a chain, stating how correct engine operating conditions are restored.(4)
3. With reference to the turbocharger for a medium speed engine:
(a) Explain why ball or roller bearings are renewed periodically; (5)
(b) State the important considerations when removing and replacing turbocharger bearings; (5)
(c) List the checks that are carried out when a turbocharger is opened for routine replacement of bearings. (6)
4. Explain the various circumstances which may cause the cylinder relief valves of a main diesel engine to lift. (6)
Sketch such a valve and explain how it is overhauled. (10)
5. Enumerate the possible causes of scavenge fires. Explain the various indication to a watch-keeper (from
instruments or otherwise) that a fire: (6)
(a) Is about to occur (5)
(b) Has broken out. (5)
6. Sketch and describe a crosshead and guide shoe for diesel engine and show the provision made for forced
lubrication. Explain how the bearing are adjusted and how it is ensured that the required clearances have in fact
been obtained. (16)
7. With reference to piston rings state the importance of EACH of the following:
(a) butt clearance (4)
(b) side clearance (4)
(c) back clearance (4)
(d) ring material. (4)
8. With reference to auxiliary diesel engine machinery :
(a) (i) state why this may be mounted on resilient mountings. (6)
(ii) state why such mountings have great flexibility;
(b) state why limit stops are provided on the mountings ; (5)
(c) state how the external piping is connected to such an engine. (5)
9. Describe how EACH of the following conditions are prevented in auxiliary boilers:
(a) feed contamination by oil (4)
(b) internal corrosion (4)
(c) furnace blow back (4)
(d) uptake fire. (4)
