1. While
an auxiliary boiler is operating at design load, which of the following actions
will occur if the automatic combustion control system detects a steam pressure
drop?
(A) More
burners will be lighted off.
(B) The
registers will open fully.
(C)
The
fuel oil valve and air damper will open wider.
(D) The
steam flow will be automatically regulated.
2. A
unit type fuel injector is used on a diesel engine to _____________.
(A) meter
the fuel
(B) produce
the proper fuel oil pressure
(C) atomize
the fuel
(D)
all
of the above
3. With
the help of explanatory sketches briefly state the lubrication system for a
large 2 stroke slow speed marine diesel engine for the following.
(A) camshaft
bearings
(B) main
bearings
(C)
piston
crosshead bearings
(D) cylinder
walls
4. If
the valve tappets in a diesel engine are set at greater clearances than those
specified by the engine manufacturer, those valves will _____________.
(A)
open
late and close early
(B) open
late and close late
(C) fail
to open when the engine is cold
(D) fail
to open at normal operating temperature
5. Regarding
a Diesel engine crankcase, the general arrangement and installation should preclude(make
it impossible) the possibility of
________.
(A)
free
entry of air to the crankcase
(B) water
entering the crankcase while engine washdowns are being performed
(C) excessive
oil leakage during periods of increased blowby
(D) subcooling
internal components
6. The
growth rate of microbiological organisms as found in some fuel supplies will
__________.
(A)
increase
in direct proportion to an increase in temperature
(B) decrease
if bleaches are added to the fuel on a regular basis
(C) remain
unchanged provided complete consumption of the fuel occurs monthly
(D) All
of the above
7. Fuel
injection pumps using the port and helix metering principle requires the use of
a ___________.
(A) crosshatched
design
(B)
lapped
plunger and barrel
(C) variable
stroke
(D) variable
cam lift
8. Internal
combustion engine crankcase vent outlets must be equipped with ______.
(A) hinged
rain guards
(B)
corrosion
resistant flame screens
(C) dipsticks
for measuring oil levels
(D) crankcase
ventilation fans
9. Proper
lubrication of the main bearings is more easily obtained in a single acting
four-stroke/cycle diesel engine than in a single acting two-stroke/cycle diesel
engine because ____________.
(A)
bearing
pressure in a four-stroke/cycle single acting diesel engine is continually reversed
(B) bearing
pressure in a two-stroke/cycle single acting diesel engine is continually
reversed
(C) the
maximum bearing pressure is higher in a single acting two-stroke/cycle diesel
engine
(D) two-stroke/cycle
diesel engines require more complicated lubrication piping
10. Increasing
the valve clearance between a valve stem and rocker arm, will result in the
valve _____________.
(A) closing
later
(B) opening
sooner
(C)
staying
open for a shorter period of time
(D) staying
open for a longer period of time
11. What
preventative maintenance should be done frequently to diesel
engine starting air receivers?
(A)
Drain
the accumulated moisture.
(B) Test
the relief valves.
(C) Watch
the temperature to prevent fluctuations in pressure.
(D) Clean
the interior to remove oil and foreign matter.
12. Friction
developing between the moving parts of a governor, governor linkage and control
valve will cause the governor to _________.
(A) react
with insufficient speed droop
(B)
fail
to react to small speed changes
(C) have
excessive sensitivity to small speed changes
(D) remain
in the neutral position
13. To
minimize corrosion, fuel oil strainer disks, spacers and scraper blades are
made of _____________.
(A) brass
(B) copper
(C) iron
(D)
monel
metal or stainless steel
14. In
a diesel engine, maximum lube oil system pressure is normally controlled
by _____________.
(A) the
capacity of the lube oil pump
(B) the
speed of the lube oil pump
(C) the
outlet pressure of the lube oil pump
(D)
a
relief valve
15. Which
of the following statements describes the function of an expansion tank in a
diesel engine cooling system?
(A) Maintains
a constant head on the system.
(B) Reduces
the likelihood of air or steam pockets formation.
(C) Provides
a low pressure point for the addition of makeup cooling water.
(D)
All
of the above.
16. Within
the cycle of a forced circulation auxiliary water-tube boiler, part of the
water flashes into steam, and the remaining hot water is _________________.
(A)
collected
in the lower portion of the steam accumulator for recirculation back to the
heating coil or water tank
(B) returned
to the lower drum via downcomers due to density difference for reheating
(C) passes
through the domestic heating system return line steam traps to the auxiliary
feed supply tank
(D) automatically
dumped into auxiliary feed heater and reheated by auxiliary exhaust back
pressure
17. Ignition
failure in an automatically controlled auxiliary boiler could be caused by
_____________.
(A)
carbon
deposits on the flame scanner
(B) high
fuel oil temperature
(C) low
fuel oil viscosity
(D) high
steam pressure
18. Which
of the fuel injection systems listed uses a spring loaded differential spray
needle valve and an individual pump
for each cylinder?
(A) Common-rail
injection
(B) Air
injection
(C)
Jerk
pump injection
(D) Distributor
injection
19. The
interior of some diesel engine saltwater heat exchangers are protected from
corrosion by the use of __________.
(A) aluminum
plates
(B) lead
cathodes
(C) copper
baffle plates
(D) sacrificial zincs
20. The
amount of chloride content in the water of an auxiliary boiler can be reduced
by ____________.
(A) adding
hydrazine
(B)
blowing
down the boiler
(C) adding
phenolphthalein
(D) adding
a sulfite chloride scavenger
21. Cooling
water pumps driven by direct reversing diesel engines are usually of the
straight impeller vane type pump with a concentric housing to ____________.
(a) provide cooling water flow when the engine
is running either ahead or astern
(b) provide
the greatest pump efficiency
(c)
prevent pump clogging from marine growth
(d) prevent
cavitation at the pump outlet
22. The
lube oil cooler is located after the lube oil filter in order for
_____________.
(A)
the
filter to operate more efficiently
(B) the
lube oil cooler to be bypassed
(C) positive
lube oil pump suction to be assured
(D) galvanic
action in the cooler to be minimized
23. A
very sudden rise in pressure during combustion accompanied by knocking of the unit or detonation usually occurs
(a) Near
the end of the pressure rise after ignition of fuel charge.
(b) Just
before the fuel charge is about to ignite.
(c)
Immediately
after the unit reaches peak pressure and before ignition of fuel charge.
(d) At
any stage of the combustion process.
24. The
main requirements which a fuel injection system must fulfill are and state each
one of the points made above are true or false
(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.
.
Ans : A, B, C (TRUE) and D (FALSE)
25. In
any marine diesel engine, air movements inside a combustion chamber is very
important. Generally speaking, air movement helps, State which of the above
points are true or false
(a) to
distribute the fuel
(b) to
mix it with air
(c) to
cool the cylinder liner
(d) to
help in optimising liner lubrication
(e) to
assist combustion
(f) to
reduce after burning
(g) to
reduce combustion temperatures.
.
Ans : All true
26. Sacrificial
zinc anodes are used on the saltwater side of diesel engine heat exchangers to
_____________.
(A)
reduce
electrolytic action on heat exchanger metals
(B) keep
heat transfer surfaces shiny and clean
(C) prevent
rapid accumulation of marine growth
(D) provide
a protective coating on heat exchanger surfaces
27. The
fuel supply system to an automatic auxiliary boiler, will be automatically
shutdown if the boiler ______________.
(A) salinity
is abnormally high
(B) steam
demand is too high
(C)
water
level is abnormally low
(D) feedwater
flow is low
28. The
crankcases of many diesel engines are kept under a slight vacuum to
_____________.
(A) improve
fuel economy
(B) increase
the air charge velocity
(C)
reduce
the risk of explosion
(D) all
of the above
29. The
rate of cylinder lubricating oil metered to each cylinder of a large,
low-speed, main propulsion diesel engine
is ______________.
(A) the
same, whether at sea, or during maneuvering
(B) adjusted
during each hour of operation while at constant
RPM
(C)
higher
at sea than while maneuvering
(D) lower
at sea than while maneuvering
30. On
a medium-speed main propulsion diesel engine, the crankpin or crank journal
bearings receive lubricating oil from
_____________.
(A) a
spindle lubricator
(B) an
oil jet
(C) internal
splashing
(D) drilled passages in the crankshaft
31. An
auxiliary engine under load continuously fluctuates even with a steady load.
The fault you diagnose could be owing to
(a)
the
quality of fuel
(b) the
quality of servicing of the governor in the last port.
(c) the
supply of charge air
(d) the
overhaul of fuel injectors done in the last decarbonisation
32. In
any diesel engine closed freshwater cooling system, the lowest pressure exists
at the _____________.
(A) jacket
water outlet
(B) cooling
water pump outlet
(C) heat
exchanger outlet
(D)
expansion
tank atmospheric vent
33. The
main advantage of unit injectors over other fuel
injection
systems is _____________.
(a)
Reducing
the need of too many high pressure fuel lines
(b) their
relatively low injection pressures
(c) reduced
wear of spray orifices
(d) the
lessened chance of fuel leaks into the engine sump
34. Cooling
the intake air supplied to a diesel engine will _____________.
A. reduce
mean effective pressure
B. decrease
average compression pressure
C. decrease
air charge density
D.
increase
power output
35. When
there is a flame failure in an automatically fired auxiliary boiler, the
____________.
A. air
supply is shut off
B.
fuel
supply is shut off
C. water
feed is shut off
D. safety
valve lifts
36. Lubrication
for the main reduction gears used with diesel engines is usually supplied by __
A. oil
from the main engine sump
B.
an
independent lube oil system
C. the
stern bearing head tank
D. the
stern bearing sump tank
37. Which
of the listed items should be secured before performing
any maintenance on a solenoid operated air start valve?
A.
Electric
power
B. Lube
oil standby pump
C. Hydraulic
switch
D. Motor
drain
38. What
is to be installed on an internal combustion engine if its cylinder bore
exceeds 200mm?
A. Crankcase
vapor monitors
B. Engine
exhaust silencers
C. Constant
pressure type turbochargers
D.
Explosion
relief valves
39. Which
of the following actions should normally be taken during each watch when the
auxiliary boiler is in operation?
A. Clean
the flame scanner photocell window.
B. Inspect
and clean all solenoid valves.
C. Lift
the safety valves by hand.
D.
Inspect
for oil or water leaks.
40. Excessive
vibration of an automatically fired auxiliary boiler can be caused by
_____________.
A. air
or water in the furnace
B.
combustion
pulses
C. fuel
oil pump failure
D. flame
failure
41. A
dirty atomizer sprayer plate in the burner of an auxiliary boiler, would be
indicated by
a. carbon
on the register doors
b. a
dazzling white atomizer flame
c.
fluctuating pressure in the windbox
d.
an
unevenly shaped burner flame
42. The
highest pressure in any closed diesel engine freshwater cooling system is at
the __
(a) jacket
water outlet
(b) expansion
tank inlet
(c) heat
exchanger inlet
(d)
cooling
water pump outlet
43. Which
of the following statements describes the function of an alarm enunciator on an
engine room alarm panel?
(a) An
alarm condition causes a light and siren to come on which remain on until the
machinery is secured.
(b)
A
flashing light comes on, followed by an audible alarm. When an alarm
acknowledge button is depressed, the audible alarm is silenced and light stays
on.
(c) An
alarm condition gives an audible and visual alarm signal, both of which are
secured when the alarm acknowledge button is depressed.
(d) An
alarm condition causes a flashing light to come on, followed by an audible
alarm. When the alarm acknowledge button is depressed, the warning light is
extinguished.
44. Excessive
leakage and premature failure of valve packing is a result of ____________.
(a)
opening a valve too quickly
(b)
jamming a valve in the closed position
(c)
low pressure fluid flow through the
pipeline
(d) a scored valve stem
45. The
purpose of a temperature sensing device installed in the stack of a small
automatically fired auxiliary steam boiler is to secure the oil burner _______________.
A.
in
the event of a flame failure
B. in
the event of a stack fire
C. when
the water level reaches the crown sheet
D. when
the feed pump discharge pressure drops to a preset minimum
46. If
the combustion control system of an automatically fired auxiliary boiler fails
to restart from the normal shutdown mode, you should check for
______________.
(A) broken
or grounded high tension leads
(B) a
faulty ignition cable connector
(C) an
incorrect electrode setting
(D)
all
of the above
47. When
taking tank soundings on a ship, coating the tape with chalk helps to ______________.
(A)
better
identify the correct reading
(B)
show the depth of any water in an oil
tank
(C)
make the tape roll easier
(D)
reduce possibility of sparks
48. When a waste
heat boiler is installed in the exhaust of a main propulsion diesel engine, the
exhaust gas bypass would be used ____________.
(a) at
high loads to prevent overheating
(b)
at
low loads to prevent corrosion in the boiler
(c) during
periods of high steam demand
(d) when
the turbocharger is in operation
49. It
is desirable for an auxiliary boiler safety valve to pop open and reseat
quickly to __________.
(a) give
warning that excessive boiler pressure has been reached
(b) prevent wire drawing of the disc and seat
(c) prevent
valve pounding
(d) provide
sufficient blowdown
50. Which
of the following statements is correct regarding grades of pipe?
(a) Stainless
steel pipe is manufactured in four general grades.
(b) Brass
pipe is manufactured in three common grades.
(c) Copper pipe is manufactured in two common
grades.
(d) The
term "extra strong" is normally associated with schedule 160 steel
pipe
51. The
crankcase of many diesel engines are kept under a slight vacuum by the ______________.
(A) scavenging
action of the piston
(B) piston
type vacuum pump taking suction off a differential manometer
(C) gland
exhausting manometer
(D)
crankcase
exhaust fan
52. Lubricating
oil systems for diesel engine journal bearings are usually lubricated by which
of the following types of lubricating
oil systems?
(A) Splash
(B) Gravity
(C) Pressure
(D) Bypass
53. Which
of the following conditions can cause above normal air temperature to develop
in the intake manifold of a four-stroke/cycle, turbocharged,
diesel engine?
(A) Clogged
air intake filters
(B) Piston
blow-by
(C)
A
defective aftercooler
(D) Faulty
exhaust valves
54. When
may the crankcase ventilation pipes or oil drain pipes of two or more engines
be connected?
(A) Propulsion
engines under 1000 shaft horsepower may share a common crankcase vent provided
the oil drains remain
separate.
(B) In
most cases it is desirable and cost effective for propulsion engines to share a common
crankcase ventilation and monitoring system.
(C)
No
interconnection may be made between the crankcase ventilation pipes or oil
drain pipes
(D) None
of the above are correct.
55. Which
of the following statements describes the unchecked growth of microbiological
organisms within a fuel system?
(A) The
dying bacteria will cause a coating to be formed on the sides of the tank
thereby decreasing corrosion.
(B) The
fuel in the tank will loose its fluidity, solidify, and
be
the cause of an expensive removal process.
(C)
Corrosion
of various metal components will occur due to the formation of hydrogen sulfide
gas.
(D) All
of the above are correct.
56. If
the feed pump for an auxiliary boiler fails to deliver the feed water to the
boiler, the cause may be
(A) high
steam pressure in the boiler
(B)
abnormally
high feedwater temperature
(C) abnormally
high boiler water temperature
(D) steam
demand exceeding feed pump capacity
57. When
lighting off an auxiliary boiler, which of the problems
listed could cause the burners to sputter?
(A) Cold
fuel oil
(B) Low
fuel oil pressure
(C) Low
atomizing steam pressure
(D) Water in the fuel oil
58. Which
of the following actions takes place in the control circuit of an automatically
fired auxiliary boiler when the desired steam pressure is obtained?
(a) A
temperature sensing device opens the circuit breaker in the burner motor.
(b)
The
high limit control secures power to the entire oil firing system.
(c) The
stack relay actuates the low limit control which breaks the ignition circuit.
(d) The
stack relay secures power to the high voltage side of the ignition transformer.
59. Telescopic
pipes to the piston of a large slow-speed main propulsion diesel engine are
designed to prevent __________.
(a) excessive
crankcase pressure
(b) excessive
lube oil temperature
(c) contamination of the lube oil by water
(d) contamination
of the cooling water by lube oil
60. Subtracting
the return flow meter reading from the supply flow meter reading on a boiler
equipped with a return flow fuel oil system, determines the amount of oil
____________.
(A) circulated
by the system
(B)
burner
throughput
(C) returned
to the settler
(D) discharged
from the pump
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