INTERNAL COMBUSTION ENGINE meo class lV objective questions with answer. (Part-2)

• Which of the bearings listed is most widely used for main and connecting rod bearings of modern diesel engines?

a)Steel-lined

b)Poured babbitt, self-aligning

c)Split roller

d)Precision insert

Answer-D

• Directional intake ports in diesel engines are used to

a)reduce air charge turbulence

b)induce air swirl

c)deflect hot combustion gas away from the valves

d)oppose the effects of piston induced squish

Answer-B

• Diesel engine main and connecting rod precision bearings are made in halves. Each half exceeds one-half the bearing circumference by a small amount. The small amount is termed

a)clearance

b)crush

c)pitch

d)thrust

Answer-B

• The piston rod scraper box incorporated in a single acting two-stroke/cycle, crosshead diesel engine serves to

a)eliminate the necessity for an oil scraper ring

b)prevent side thrust and cylinder scoring

c)prevent sludge and dirty oil from entering the crankcase

d)scrape oil and carbon deposits off the cylinder walls

Answer-C

• The proper location for journal bearing oil grooves is

a)in the region of the load bearing surface

b)as a side relief where the two shells meet

c)at the bottom of the bearing

d)halfway between bottom and where shells meet

Answer-B

• How are hydraulic valve lash adjusters on diesel engine rocker arm assemblies lubricated?

a)Cup-fed grease

b)Sealed self-lubricators

c)Metered hydraulic oil supply

d)Forced lube oil supply

Answer-D

• Main propulsion diesel engines having a bore exceeding 300 mm are to have at least

a)two independent means of starting the engine

b)five air starting valves to permit the admission of starting air at any crank angle

c)one (explosion relief) valve at the position of each main crank throw

d)two engine driven lube oil pumps capable of parallel operation

Answer-C

• Integral water jacket liners use O-rings near the bottom of the liner, these O-rings serve to

a)form a water seal between the liner and engine block

b)allow for slight misalignment of the liner

c)prevent the escape of lubricating oil from the crankcase

d)ensure proper temperature flow between the liner and engine block

Answer-C

• 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

Answer-C

• A characteristic of a bearing material which permits small dirt particles to become embedded in the surface and is

a)desirable, as it will prevent damage to the journal surface

b)desirable, as it will assist in keeping the lube oil filters clean

c)undesirable, since the embedded particles will score the journal

d)undesirable, since the particles will interfere with lube oil flow

Answer-A

• Most fuel injection nozzles are opened by

a)fuel oil pressure

b)a cam operated follower

c)a spring-loaded pressure plate

d)timing gears keyed to the crankshaft

Answer-A

• Which of the following devices controls the discharge flow rate of an attached, positive displacement, rotary gear, diesel engine, lube oil pump?

a)A pressure regulating valve

b)A pressure relief valve

c)The engine speed

d)An orifice

Answer-C

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

a)reduce water temperature

b)reduce water turbulence

c)provide an air cushion

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

Answer-D

• 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

Answer-D

• 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 air cock when fires are lighted

c)Provides a low pressure point for the addition of makeup cooling water

d)All of the above

Answer-C

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

a)piston rod guides

b)engine thrust bearing

c)crosshead bearing

d)main shaft flexible coupling

Answer-B

• Scavenging in a four-stroke/cycle diesel engine occurs during the

a)last part of the exhaust stroke, and the first part of the intake stroke

b)last part of the intake stroke only

c)early part of the injection stroke only

d)early part of the power stroke

Answer-A

• In a large, slow-speed, main propulsion diesel engine, which of the parts listed is under tension when the engine is running?

a)Bed plate

b)Column

c)Entablature

d)Tie rod

Answer-D

• 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

Answer-A

• In 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

Answer-b

• With respect to the flow of lubricating oil through a diesel engine, the lube oil coolers are located after filters in order to

a)allow filtration of less viscous oil

b)decrease the pressure drop across the filter

c)improve overall filtration

d)all of the above

Answer-D

• Passages are drilled in the crankshafts of diesel engines to provide lubricating oil to the

a)main bearings

b)connecting rod bearings

c)piston pin bushings

d)All of the above

Answer-D

• The outlet from an expansion tank of a closed freshwater cooling system should be piped to the

a)cylinder head water outlet header

b)cylinder jacket inlet main

c)heat exchanger inlet connection

d)jacket water pump suction line

Answer-D

• The intake valves in diesel engine are reseated by

a)cam followers

b)push rods

c)combustion gases

d)valve springs

Answer-D

• Small amounts of moisture are necessary to trigger the growth of microbiological organisms found in some marine fuels. Some sources of water contamination are

a)tank surface leakage

b)humidity and condensation

c)improper tank washing procedures

d)All of the above

Answer-D

• The main function of tie rods in the construction of large, low speed diesel engines is to

a)stiffen the bedplate in way of the main bearings to increase the engine`s longitudinal strength

b)accept most of the tensile loading that results from the firing forces developed during operation

c)mount the engine frame securely to the hull to prevent shaft coupling misalignment

d)connect the crosshead solidly to the piston rod

Answer-B

• On most modern diesel engines,the main and connecting rod bearings receive their lubricating oil by

a)banjo feed

b)splash feed

c)gravity feed

d)pressure feed

Answer-D

• 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

Answer-D