1.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 ANS
– A
2. In a diesel engine, late fuel injection
is indicated by black or gray exhaust smoke with ______________.
(a) low firing pressure
(b) low exhaust temperature
(c) mechanical knock in each cylinder
(d) fuel knock in each cylinder
ANS
– A
3. 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.
ANS
B
4
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
ANS
A
5
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.
ANS
B
6. A diesel engine should not be operated
at low loads for long periods of time
because _____________.
(a) heavy carbon deposits will buildup on
the valves and in the exhaust
(b) fuel dilution is increased at low load
(c) exhaust valves may be damaged
(d) all of the above
ANS
D
7. The major cause of fuel pump and
injection system problems is _____________.
(a) improper adjustments
(b) contaminated fuel
(c) kinked fuel lines
(d) excessive engine vibration
Briefly
Justify Your Answer
ANS
B
8. A dirty fuel oil filter element can be
detected by ________.
(a) visual inspection of the element
(b) the pressure drop across the filter
(c) high fuel oil tank temperature
(d) increase flow rate from the filter
ANS
B
9. In a two-stroke/cycle diesel engine,
the process of scavenging begins as the ________.
(a) piston nears and passes TDC
(b) early part of the upstroke
(c) piston passes BDC
(d) early part of the downstroke
ANS
B
10) A
large, low-speed, main propulsion diesel engine uses sea water to directly cool
the
a)cylinder
heads
b)exhaust
valves
c)scavenging
air
d)injectors
ANS-
C
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