問題一覧
1
Crank web deflection readings will give a positive indication of ___________.
worn main bearing journals
2
Why do most temperature control valves in diesel engine closed freshwater cooling systems bypass the flow of jacket water around the cooler instead of around the engine?
excessive cooling would take place in the heat exchangers at high loads
3
If the temperature in a hot air manifold were found to be 122oF, what will be the equivalent reading on the centigrade scale?
50⁰C
4
The minimum design height of the DC heater is determined by the _____.
Minimum net positive suction head required by the main feedpump
5
Most large main propulsion diesel engines use a duplex lube oil strainer to _______.
ensure a positive flow of oil at all times
6
1. Which steam plant watch operating condition will require priority attention over the other conditions listed?
Low water level main boiler
7
What might be the cause of excessive vibration of an automatically fired auxiliary boiler?
Combustion pulses
8
A dirty atomizer sprayer plate in the burner of an auxiliary boiler, would be indicated by ________.
an unevenly shaped burner flame
9
Throttling a burner air register on an auxiliary boiler could result in ________.
smoky boiler operation
10
A lube oil filter can be used to remove most contaminants from lube oil. What contaminant will remain in the lube oil after filtering?
Fuel/Diesel oil
11
The watch engineer finds the refrigeration compressor has blown the shaft seal. In this situation, he should _
secure the compressor at once and close the suction and discharge valves
12
A pneumercator is an instrument used to indicate _____.
tank fluid level
13
Rapidly discharging condensate into the DC heater during normal steaming conditions could cause _____.
Decrease in auxiliary exhaust pressure
14
Diesel engines driving alternators operating in parallel must maintain a set frequency regardless of load changes. What is the governor characteristic used to accomplish this?
compensation
15
What is the main reason that auxiliary steam is normally attemporated before entering the feed heater of a flash evaporator?
To reduce the rate of scale formation on heating surfaces
16
While at sea, the flash type evaporator is discharging the output to the distill tanks. If it becomes necessary to reduce the feed water temperature below 165oF, you should _____.
Continue the current evaporator operation
17
The DC heater functions to _____.
Store, heat, and deaeratefeedwater
18
Why is condensate being pumped from the condenser to the DC heater instead of directly to the boiler?
Condensate should be deaerated before entering the boiler
19
What maybe the cause of injection lag in a diesel engine?
The diesel fuel used having a high viscosity
20
What reading will be obtained if we use a dry uncoated sounding rod or tape to measure the depth of water in a reserve feed water tank?
Very inaccurate
21
Cooling water pumps driven by direct‐reversing diesel engines are usually ______.
straight impeller vane with concentric housing
22
Increasing the valve clearance between a valve stem and rocker arm, will in the valve ________
staying open for a shorter period of time
23
Reducing the clearance between a valve stem and rocker arm will result in the valve __________.
having a longer duration of opening
24
Diesel engine injection lag is caused by ____________.
compressibility of the fuel
25
A change in engine speed is required before a governor is able to make a corrective movement of fuel rack. This aspect of governing is commonly expressed as a percent and is known as ___________.
governor sensitivity
26
Exhaust pyrometer readings provide an indication of the _______.
distribution of the load between engine cylinders
27
Exhaust valve grooving and corrosion is caused by certain components of residual fuel oil. These components are sodium, sulfur, and ___________.
Vanadium
28
You are operating a main propulsion diesel engine at a constant load when the jacket temperature begins to rise. This could be caused by _________
a piston about to seize
29
A lube oil filter can be used to remove most contaminants from lube oil. What contaminant will remain in the lube oil after filtering?
Fuel/Diesel oil
30
What reading will be obtained if we use a dry uncoated sounding rod or tape to measure the depth of water in a reserve feed water tank?
Very inaccurate
31
Which of the listed fuel oil ignition methods are commonly found on automatically fired auxiliary boilers aboard merchant vessels?
A high energy electric spark
32
What is the proper way of storing an oxygen and acetylene cylinders?
Horizontal with the cylinder caps screw on
33
The effective stroke of a constant‐stroke, individual, fuel injection pump is varied by the __________.
control rack
34
Which of the filters listed will deplete the additives in lubricating oil?
Adsorbent filter
35
Oil accumulating in the exhaust piping or manifold of a diesel engine can be caused by ______.
worn valve guides
36
If the temperature is a hot air manifold were found to be 122⁰F, what will be the equivalent reading on the centigrade scale?
50⁰C
37
A pyrometer is capable of producing a voltage by _____.
heating a junction of two dissimilar metals
38
The device most commonly used to measure the exhaust gas temperature of a diesel engine cylinder is called a _______.
pyrometer
39
The DC heater automatic level dump valve is used to _____.
Drain excess feedwater to the distilled water tank
40
Diesel engines driving alternators operating in parallel must maintain a set frequency regardless of load changes. What is the governor characteristic used to accomplish this?
Compensation
41
Valve lash, or clearance refers to the _________.
clearance between the top of the valve stem and the rocker arm
42
What might be the cause of excessive vibration of an automatically fired auxiliary boiler?
combustion pulses
43
Which of the listed fuel oil ignition methods are commonly found on automatically fired auxiliary boilers aboard merchant vessels?
A high energy electric spark
44
A pneumercator is an instrument used to indicate _____.
Tank fluid level
45
The bulk of the solid material entering a centrifugal purifier with lube oil is ________.
trapped in the bowl
46
Fuel combustion in a diesel engine cylinder should begin just before the piston reaches top dead center and should ___________.
continue through the after‐burning period
47
What maybe the cause of injection lag in a diesel engine?
The diesel fuel used having a high viscosity.
48
Where is the contaminated oil enters the centrifuge in a disk type centrifugal purifier?
At the top through the regulating tube
49
Which of the following problems can cause fluctuating pressure in the closed cooling system of a main propulsion diesel engine?
cavitation in the cooling water pump
50
Excessive lubricating oil consumption in a running diesel engine can be caused by _________.
excessive valve‐guide clearance