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The correct answer is (a) True

To elaborate: Oil should be heated before passing it through the centrifuge and then it is cooled before supplying it to the ENGINE. As heat is developed due to friction between the moving parts, the cooling is DONE by using water from the cooling TOWER.

Right option is (c) To reduce the disturbance

Explanation: Due to the presence of friction, WEAR and tear of the engine PARTS takes place reducing the engine life. The lubricant introduced forms a THIN film between the rubbing surfaces and prevents metal to metal contact.

The correct choice is (c) REDUCING noise

Explanation: Muffling is the process of reducing the noise. The EXHAUST system must CARRY approximately 0.23m^3/min-0.30m^3/min of gases per kilowatt developed, at the average exhaust temperature. Muffling of the exhaust noise is DONE by using silencers LOCATED outside building.

The correct answer is (a) Corrosion

To ELABORATE: Corrosion naturally occurs around the battery.Electrolyte condensation contains corrosive sulfuric ACID, which destroys the METAL of battery terminals, cable ends and battery HOLD down parts. To clean away the corrosion, USE a mixture of baking soda and water.

The correct ANSWER is (b) engine day tank

Easiest explanation: The fuel oil may be delivered at the plant side by trucks, railroad tank cars or barge and tankers. From tank truck the DELIVERY is done using the UNLOADING FACILITY to main storage tanks. This fuel is then transferred by pumps to small service storage tanks know as engine day tanks.

The correct CHOICE is (a) Engine misfires at low LOADS

To elaborate: The AIR system contains an INTAKE manifold located outside the building with filter to catch dirt which would otherwise cause excessive wear in the engine. If the atmospheric temperature is too low, engine misfires at low loads and hence it is necessary to install a heating element using exhaust gas.

Correct choice is (c) Eliminate HEAT coming out of engine

For EXPLANATION: The system includes water circulating PUMPS, cooling towers are spraying ponds and water FILTRATION or treatment plant. The purpose of cooling system is to ensure the life of cylinder by extracting the heat developed from the engine cylinder walls and hence keeping the temperature within the safer range.

Right option is (b) COMMON rail direct injection

The EXPLANATION: CRDI id common rail direct injection, which says direct injection of FUEL into cylinders VIA a common single rail called single line which is connected to all the fuel injectors. This system is commonly equipped in diesel engines.

The correct choice is (c) Capacitor DISCHARGE ignition

Easy EXPLANATION: CDI stands for capacitor discharge ignition or thyristor ignition is a type of AUTOMOTIVE electronic ignition system which is widely used in the outboard MOTORS, MOTORCYCLES, chainsaws, lawn mowers and some cars.

Right answer is (a) 1 to 50MW

The explanation is: Since the INVENTION of diesel engine, diesel engine plants are finding increased application as either CONTINUOUS or peak load source of POWER generation. DUE to economy of operation DG plants are used to generate power in the range of 1 to 50MW capacity.

Correct OPTION is (d) High speed centrifuges

For explanation I would say: Rough cleaning of OIL is done by passing oil through high speed centrifuges. Centrifuges can be done by PERIODIC centrifuging of the entire lubricating oil or by CONTINUOUS cleaning of a small fraction of it by splitting the oil from main flow and RETURNING back to main stream.

The correct answer is (c) Hydrogen

The EXPLANATION is: When charging, the battery will emit hydrogen gas; it is therefore EXTREMELY important to keep the FLAMES and sparks away from battery. It is also advisable to wear goggles and GLOVES while servicing the battery.

Correct answer is (B) False

Easy explanation: The INJECTION systems, especially the parts that actually are manufactured with great accuracy meter and inject the fuel. Some of the tolerances between the moving parts are so small that they REQUIRE some special attention during manufacture. HENCE the injection systems are costly.

Correct answer is (c) Air FILTER REMOVES DUST from air

The best explanation: Air filter removes the dust from air before entering the engine. Air actually contains oxygen which supports the combustion inside the engine CHAMBER. And ALSO helps in moving/taking out the exhaust fumes which are produced after combustion.

Right CHOICE is (a) For continuous reliable operation

To EXPLAIN: For continuous reliable operation attention should be GIVEN to oil cleaning. For this PURPOSE filters with centrifuges or chemical action have been employed. Mechanical filters include cloth bags, wool, felt pads, paper discs and cartridge of porous MATERIAL.

The correct choice is (a) Full PRESSURE lubrication

To elaborate: In full pressure lubrication splash rods equipped. An OIL pump supplies lubricating oil to many parts of the engine through duct system and to the crank shaft through drilled holes. The CYLINDER walls are LUBRICATED by oil mist that is slung OUTWARD by the splash rod connected to flywheel from pool of oil.

The correct option is (a) LOCK

The BEST I can explain: In lock position all circuits are OPEN and the steering wheel is in lock position.In some cars, the transmission lever cannot be moved in this position. If the steering wheel is applying pressure to the LOCKING mechanism, the KEY might be hard to turn.

Correct option is (a) Gasoline direct INJECTION

Explanation: In non-diesel IC ENGINES, GDI (Gasoline direct injection), also known as petrol direct injection, Fuel satisfied ignition etc. Emission levels can be EASILY and accurately controlled with diesel systems.

The correct choice is (c) gear transmission

For explanation I would say: This switch opens (denies current to) the starter circuit when the transmission is in any gear but NEUTRAL on automatic transmissions. This switch is normally connected to the transmission linkage or DIRECTLY on the transmission. Most cars utilize this same switch to apply current to the backup lights when the transmission gear is put in REVERSE.

The correct answer is (b) heart

Explanation: Function of FUEL INJECTION system are:

Filter the fuel.

Measure the correct quantity of fuel to be injected.

Proper TIME the fuel injection.

Control the rate of fuel injection.

Break up the fuel into fine particles.

Properly distribute the fuel in the combustion chamber.

Right option is (a) Dry-TYPE

For explanation: Dry type of filter is made up of cloth, felt and glass WOOL etc. the filters catch dirt by CAUSING it to cling to the surface of filter material. The CAPACITY of such filters drops progressively when they are in use. The cleaning is DONE by amount of air used by the engines and dust concentrate in it.

The CORRECT option is (a) To support combustion

Easy explanation: A large diesel engine PLANT REQUIRES about 0.076 m^3/min to 0.11m^3/min of air per KW of power developed inside the engine. Air contains LOT of dust; HENCE it is necessary to remove the dust content in the atmospheric air.

Right option is (c) Electronic controls

The EXPLANATION is: The recent difficulty added to the stating system is electronic controls in engines. Some electronic control machines may NEED some minimum number of REVOLUTIONS at a minimum SPEED before energizing the fuel system.

The CORRECT choice is (c) Start switch position

The EXPLANATION is: Power is SUPPLIED to the ignition circuit in start switch position. That is why the media stops PLAYING in the start position. This position of the ignition switch is spring loaded so that the starter is not engaged while the ENGINE is on. This position is used momentarily, just in order to activate the starter.

The CORRECT option is (a) 2

Easy explanation: ATOMIZATION of FUEL can be done by (i) Air blast (ii) Pressure spray. In the olden days engines USED air fuel injection at about 70bar which is sufficient not only to inject the oil, but also to atomize it for rapid and thorough combustion. The expense of PROVIDING an air compressor tank leads to the development of “solid” injection.

Correct option is (c) For a Month’s requirement

Easiest explanation: The MINIMUM STORAGE capacity of at least a month’s requirement of FUEL is generally kept in bulk. However, when the advantage of seasonal fluctuations in cost of oil is to be availed, it may be necessary to provide storage for a few months requirement.

Right choice is (b) Turbocharged direct injection

Best EXPLANATION: TDI stands for Turbocharged direct injection is a design of turbo diesel engines. These are USED in vehicles, ALSO used in the marine engines. In this fuel injector SPRAYS atomized fuel into main combustion CHAMBER of each cylinder.

Right choice is (c) to be exposed to air

The explanation is: Because batteries emit HYDROGEN gas while charging, the battery case cannot be completely sealed. Years ago there was a vent cap for each cell and we had to REPLENISH the CELLS when the electrolyte evaporated. Today’s batteries (maintenance free) have small vents on the side of the battery; the gases emitted have to GO through baffles to escape.

The correct choice is (b) lead-acid storage battery

To explain: The automotive battery, also known as Lead-acid storage battery is an electrochemical device that produced VOLTAGE and delivers CURRENT. In an automotive battery we can RESERVE the electrochemical action, thereby RECHARGING the battery, which will then give MANY years of service.

Correct OPTION is (B) Cold cranking amps

Explanation: Today’s batteries are RATED in term of cold cranking amps. This represents the current that the battery can produce for 30 seconds at 0^oC before the battery voltage DROPS below 7.2 volts. An average battery today will have a CCA (Cold Cranking Amps) of 500.

The correct choice is (c) Device that allows small electrical current to control large electrical current

Easiest EXPLANATION: A relay is a device that allows a small amount of electrical current to control a large amount of current. An automobile STARTER uses a large amount of current to start an engine. If we allow MUCH current to go through the ignition switch, we would NEED a very large switch.

Right choice is (d) HIGH GRADE filters

Explanation: Due importance should be given for cleanliness in HANDLING bulk fuel oil. Dirt particles will ruin lap of injection pumps or PLUG the injection nozzle orifices. Thus, high grade filters are of great importance to the diesel oil supply system.

Correct answer is (b) False

The best I can EXPLAIN: DG plants are more efficient than any other heat engine of comparable size. It is AVAILABLE at very short delivery TIMES and can be started quickly and brought into service. It can burn FAIRLY wide range of fuels.

The correct option is (C) Silencers

The BEST explanation: Engine sound during operation may be transmitted back through the air intake systems to the outside air. In such cases a SILENCER is provided between the engine and the intake. It is a light WEIGHT steel PIPE.

Right answer is (d) Cold

The best I can explain: The engine cranking is difficult in colder temperatures especially if engine is directly driving other machine equipments such as TORQUE converter or hydraulic PUMPS. Cold engine oil adds to the load on starter, and this load may increase by 3 to 4 TIMES what it would normally be in warmer WEATHER.

Right choice is (a) Electrolyte

Explanation: The electrolyte INSIDE the battery is a mixture of sulfuric acid and WATER. Sulfuric acid is very corrosive; if it gets on your SKIN it should be flushed with water. The AUTOMOTIVE battery requires special handling. If it gets in your EYES it should be flushed with mild solution of baking soda and water.

The correct choice is (c) To eliminate friction between the mating parts

Explanation: The system INCLUDES OIL PUMPS, oil TANKS coolers and connecting pipes. The system reduces the friction between the moving parts and HENCE reduces wear and tear. Lubricating oil also controls the temperature at mating point.

Correct option is (d) Supercharger INCREASES PRESSURE of AIR

To EXPLAIN: Supercharger increases the pressure of air at engine inlet and hence increases engine power. They are usually driven by the engines. It usually situated after the air FILTER. The power for supercharger can be provided by mechanical means of belt, gear, shaft or chain connected to engine’s crankshaft.

Right option is (c) By providing torque

To explain: MINIMUM cranking speed is achieved by providing the necessary torque, which is ACTUALLY a purpose of STARTER motor. As the starter motor rotates the FLYWHEEL, the crankshaft is TURNED, which then starts piston movement.

Correct option is (c) 3

To ELABORATE: There are three most commonly used FUEL injection systems in diesel POWER station, they are:

i) Common rail injection system.

ii) Individual pump injection system.

iii) DISTRIBUTOR.

The correct choice is (b) 2

For explanation I would SAY: There are basically two types of common rail injection systems which are by using single PUMP and using controlled pressure system. In case of single pump, it supplies high pressure fuel to HEADER. In the controlled pressure system, it has a pump which maintains a set head pressure.

Correct answer is (b) Very Small

For explanation: Fuel INJECTION system is the heart of diesel engine. In an injection system very small quantity of fuel must be measured out, injected, atomized, and mixed with combustion air. The mixing problem becomes more difficult. The larger the cylinder and faster is the ROTATIONAL speed. However, special combustion arrangements such as pre-combustion CHAMBERS, air cells etc, are NECESSARY to ensure good mixture.

Correct answer is (c) 1960

Explanation: The COMMON rail SYSTEM prototype was developed in late 1960s by Robert Huber of Switzerland and the technology further developed by DR. MARCO Ganser at the Swiss federal institute of technology in Zurich, later of Ganser-Hydromag AG (est. 1995) Oberageri.