Advance Diesel Final

The section of the turbocharger which would be connected to the aftercooler inlet is labeled _______ _. MO-0080

B

Fuel is admitted to a diesel engine cylinder through the _______.

injector nozzles

On a typical turbo-charged marine diesel engine, what type of blower/compressor is used within the turbocharger?

Centrifugal

Which of the following problems could develop due to the accumulation of oil vapors in the crankcase of a diesel engine?

Crankcase explosion

Which of the terms listed below represents the operational speed at which excessive engine vibration is created?

Critical speed

Which of the listed types of superchargers will NOT have a volumetric capacity proportional to engine speed?

Exhaust gas turbocharger

Which of the routine maintenance procedures listed is required for starting air receivers?

Frequent draining of accumulated moisture.

Which of the following devices will increase the power output of a diesel engine without increasing its frictional load?

Turbine-driven centrifugal blower

Compared to a naturally aspirated diesel engine, a supercharged diesel engine has ________ .

a cylinder air charge of higher pressure

An increase in the air inlet manifold pressure of a diesel engine will result in a/an _________.

a decrease in fuel consumption per horsepower-hour

The purpose of an oil mist detector in a main propulsion diesel engine is to warn of _________ .

a possible overheated bearing

In a diesel engine closed freshwater cooling system employing a radiator, the proper water temperature can be obtained by _______.

adjusting the radiator louvers

The highest pressure in a diesel engine cylinder normally occurs _______.

after TDC

The expansion tank for a diesel engine closed cooling system is designed to maintain a constant head on the system and __________.

allow for an increase in water volume as the engine warms up

A three-way thermostatic control valve regulates the diesel engine cooling water temperature by passing a portion of the water _______.

around the cooler

The proper location for journal bearing oil grooves is _______.

as a side relief where the two shells meet

Reduction gear casings are vented in order to ________.

avoid a buildup of pressure within the gear case

Diesel engines are classified as reciprocating internal combustion engines because they ________.

burn fuel in a closed chamber which imparts linear motion to Pistons

For a continuous operation diesel engine, a duplex filter unit would be the best arrangement because _______ .

changing filter elements would not interrupt engine operation

The temperature at which an adjustable bellows type thermostatic valve operates is determined by ______.

changing the spring compression opposing the bellows

Before starting a diesel engine, you should always _______.

check the crankcase oil level

The process of scavenging a two-stroke/cycle diesel engine serves to .

cool the exhaust valves

The highest pressure in any closed diesel engine freshwater cooling system is at the ___________.

cooling water pump outlet

The linear motion of a diesel engine piston is converted into the rotary motion required to drive gears, propeller shafts, and generators by the _______.

crankshaft

Component "U" of the diesel engine shown in the illustration is called the__________. MO-0122

crankshaft counterweight

Before starting a diesel engine that has an engine driven lube oil pump, you should __________.

cut in the lube oil cooler

The diesel engine component labeled "3", shown in the illustration is called the _________. MO-0122

cylinder head

In a naturally aspirated diesel engine, the volume of air intake is directly associated with engine _______.

displacement

During the valve overlap period, the exhaust pressure of a turbocharged, four- stroke/cycle diesel engine must be less than the intake manifold pressure to ensure _____________.

effective cylinder scavenging and cooling

The operating speed of a turbocharger is directly dependent upon .

engine load

On a large diesel engine installation, crankshaft axial alignment is maintained by the ________ .

engine thrust bearing

Valve '1', as shown in the illustration when should be operated when _______ _. Illustration MO-0077

entering or departing port

At rated engine load and RPM, the diesel engine turbocharger is powered by ____________.

exhaust gases

A magnetic strainer is primarily used in diesel engine reduction gear oil systems to remove small particles of ________ .

ferrous materials

The lube oil strainer shown in the illustration is used on the reduction gear of a mid-size diesel engine. The strainer elements consist of _________ .

fibrous braid

Kingsbury thrust bearings are lubricated by _______.

flooding the thrust bearing assembly with oil

Corrosion inhibitors and/or soluble oils are added to diesel engine cooling systems to ____________.

form a protective film on metal surfaces

The illustrated device is operated directly by _________. MO-0041

fuel oil pressure

Heat exchangers are most commonly found in a small auxiliary diesel engine ______ .

governing system

The relative air pressure in the inlet manifold of a turbocharged diesel engine is usually

greater than the average exhaust manifold pressure

Ethylene glycol, when used as a coolant in a closed cooling system for a diesel engine, is more advantageous than untreated raw water because of it ___________.

has a lower freezing point and higher boiling point

Whether using a centrifuge or a simple filter, oil cleaning and filtration will be the most effective when the oil is at a _________ .

high temperature and a low viscosity

After cooling of a turbocharged diesel engine will result in .

higher torque and higher brake horsepower

An electric heater built into some smaller diesel engines is used to ______.

increase jacket water temperature for easier starting in cold weather

Cooling the intake air supplied to a diesel engine will _________ .

increase peak power output

Fuel injection systems are designed to primarily meter fuel, atomize fuel, and _________ .

inject fuel at the proper time

Fuel oil discharged into the diesel engine cylinder is atomized at the ________ .

injector nozzle tip

In a diesel engine jacket water cooler, with seawater cooling the fresh water, the ________.

jacket water pressure should always be greater than the sea water pressure

A closed freshwater cooling system is commonly used with marine diesel engines because the _________.

jacket water temperature is more easily controlled

Fuel injection pumps using the port and helix metering principle requires the use of a ________

lapped plunger and barrel

The cubic inch (or liter) displacement of a cylinder is determined by the diameter of the piston and the ________.

length of the stroke

The thermal energy produced by an internal combustion engine is transformed into _______.

mechanical energy

Connecting rods in a diesel engine are used to connect the ________.

piston to the crankshaft

Babbitt is a metal alloy commonly used for lining _______.

precision bearings

Where would a coarse screen wire-mesh strainer normally be found on a diesel engine lubrication system?

pump suction line

The power consumed during the scavenging process of a diesel engine is known as the ___________.

pumping loss

Sacrificial zinc anodes are used on the saltwater side of diesel engine heat exchangers to _______.

reduce electrolytic action on heat exchanger metals

In the starting process of a diesel engine, the main object is to attain the compression conditions sufficient to ________.

reduce friction

When checking zincs in saltwater cooled heat exchanger, you should ________.

replace the zincs if they are approximately 50% consumed

The bearing shown in the illustration is designed to carry thrust when applied __________. Illustration MO-0001

right to left only

The amount of fuel delivered by a helical plunger fuel injection pump is controlled by ________ .

rotation of the pump plunger

Forcing the exhaust gases from the cylinder of an operating two-cycle diesel engine with the aid of a blower is known as________ .

scavenging

A normally operating diesel engine is shutdown by _______.

securing the fuel supply

A naturally aspirated diesel engine at full throttle will have an intake manifold pressure _________.

slightly less than atmospheric pressure

Hydraulic couplings will transmit torque equal to the input torque by means of energy changes in a rotating vortex of liquid. For the vortices to form there must be _________.

slip between the impeller and runner

Cooling water pumps driven by direct-reversing diesel engines are usually __________.

straight impeller vane with concentric housing

The process of supplying a diesel engine cylinder with air at a pressure greater than atmospheric is called .

supercharging

Lube oil cannot be efficiently filtered if it's ________ .

temperature is too low

The lube oil cooler is located after the lube oil filter in order for _________ .

the filter to operate more efficiently

The expansion tank in a diesel engine closed freshwater cooling system is located at _________.

the highest point in the system

The main advantage of unit injectors over other fuel injection systems is ________ .

the lack of high-pressure fuel lines

If the compression ratio is increased on any diesel engine _________.

thermal efficiency will increase

One advantage of electromagnetic slip couplings is ________.

torsional vibrations are reduced

As found in a reduction gear drive system, thrust bearings serve to ________.

transmit the force produced by the propeller to the structure of the ship

Some diesel engines are supercharged with a ___________.

turbocharger

The load is always placed on the lower half of the main bearings in a/an ________.

two-stroke/cycle engine

The device shown in the illustration is commonly used to ___________. Illustration MO- 0080

utilize the flow of exhaust gases to supercharge the engine

Movement of the pump control rack in a fuel injection system using individual plunger-type pumps ___________.

varies the quantity of fuel delivered

What would be considered a normal temperature increase between the inlet and outlet jacket cooling water of a medium or high-speed diesel engine operating at normal load?

10° to 20°F

In the illustrated diesel engine, which labels points to the piston? MO-0122

4

The diesel engine wrist pin in the illustration is indicated by the component labeled __________. MO-0122

7

The theoretical minimum compression ratio necessary to ensure compression ignition in a direct injection diesel engine is ________.

8:1

What statement is true concerning the charge air system of a modern turbocharged slow- speed two-stroke cycle diesel engine?

A charge air cooler is usually provided to increase the charge air density.

What statement is true concerning the charge air system of a modern turbocharged slow-speed two-stroke cycle diesel engine?

An electrically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at low engine speeds and loads.

What is the function of the main thrust bearing?

Transmits propeller thrust to the hull.

Which of the following reasons represents why the designed compression ratio of a gasoline engine is lower than that of a diesel engine?

The heat of compression is not used as an ignition source of the fuel.

Why will a turbocharged diesel engine produce black smoke if the excessive additional load is applied too quickly?

The inertia of the turbocharger rotor causes a time lag which delays the turbocharger speed increase.

Which of the following statements is true concerning the main diesel engine oil cooler?

The oil pressure is greater than the cooling water pressure

What is the function of the aftercoolers installed in the diesel engine air intake system?

Increase the air density

Which of the statements represents a characteristic of the thrust collar in a Kingsbury thrust bearing?

It turns with the shaft and the pivot shoes do not rotate.

Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and an individual pump for each cylinder?

Jerk pump injection

Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started?

Lube oil pressure

To minimize corrosion, fuel oil strainer disks, spacers and scraper blades are made of

Monel metal or stainless steel

Which of the following is an example of a solid bearing?

Piston pin bushing

Which of the bearings listed below is most widely used for the main and connecting rod bearings of a modern high-speed diesel engine?

Precision insert

Where is the air charge for an air starting system stored?

Pressurized Tank

Which of the following types of bearings are used as line shaft bearings?

Ring-oiled, Babbitt-faced, spherical seat, shell

What type of reduction gear would most commonly be used with twin medium-speed propulsion diesel engines driving a single shaft?

Single reduction, double input

Which of the listed substances can be satisfactorily removed from diesel fuel by centrifuging?

Sludge

Which of the following methods is used to securely fasten the Babbitt lining of a reduction gear bearing to its shell?

The Babbitt is centrifugally spun into the bearings or cast under a pressure head