July17 MECHANIC (DIESEL) THEORY SEMESTER-II
In which working cycle is completed in four stroke engine?
a) One revolution of the crankshaft
b) Two revolution of the crankshaft
c) Three revolution of the crankshaft
d) Four revolution of the crankshaft
In which parts are to be joined between cylinder head and engine block?
a) Valve guide
b) Compressor ring
c) Combustion chamber
d) Head gasket
A two stroke cycle engine gives the number of power strokes as compared to the four stroke cycle engine at the same engine speed.
a) Half
b) Same
c) Double
d) Four times
A two stroke cycle engine gives mechanical efficiency than a four stroke cycle engine-
a) Higher
b) Inwer
c) Same
d) None of these
After fitting rings over piston, it is inserted in cylinder with the help of a special tool called-
a) Ring Expander
b) Ring cleaner
c) Ring compressor
d) Ring groove cleaner
Compression ratio of diesel engine is- -
a) The ratio of volumes of air in cylinder before compression stroke and after compression stroke
b) Volume displaced by piston per stroke and clearance volume in cylinder
c) Swept volume/Cylinder volume
d) Cylinder volume/Swept volume
The main function of intake manifold is
a) Reduce intake noise
b) Provide the mixture of air and fuel
c) Distribute intake air equally to the cylinder
d) Cools the intake air to a suitable temperature
The heat transfer from coolant to air in radiator of an automobile engine take place by-
a) Radiation only
b) Convention only
c) Convention & Radiation only
d) Conduction, Convention & Radiation
Water circulation in a radiator take place from
a) Lower tank to upper tank
b) Upper to lower tank
c) Engine to upper tank
d) Engine to water pump
Supercharger is the function of-
a) Supplying the intake of an engine with air at a density greater than the density of the surrounding atmosphere
b) Providing forced cooling air
c) Supplying compressed air to remove combustion products only
d) Injecting excess fuel for raising more load
In case of gas turbines, the gaseous fuel consumption guarantees are based on-
a) Low heat value
b) High heat value
c) Calorific value
d) Net calorific value
Engine pistons are usually made of aluminium alloy because it.
a) Is lighter
b) Warless
c) Absorb shocks
d) Does not react fuel & lubricant oil
Which is more viscous lubricant oil?
a) SAE 30
b) SAE 40
c) SAE 50
d) SAE 80
In the opposed piston diesel engine, the combustion chamber is located -
a) Above the piston
b) Below the piston
c) Between the piston
d) Anywhere
Piston rings are usually made of-
a) Cat iron
b) Cast steel
c) Aluminium
d) Brass
The forced fed lubrication system means that the oil is delivered to the engine by-
a) Gravity b) The pressure created by the oil pump
c) Splashing action of the crankshaft d) None of these
Exhaust pipes of engines are covered with insulating material in order to
a) Keep the exhaust pipes warm b) Increase engine efficiency
c) Reduce heat transfer to engine room
d) Conserve heat
Fuel consumption with increase in "back pressure" will-
a) Increase
b) Decrease
c) Depend on the factor
d) Remain unaffected
In which parts of battery charging rotates crank fan belt?
a) Water pump pulley
b) Dynamo
c) Self Starter
d) Magneto
In order to eliminate knocking in compression ignition engines, there should be-
a) Short delay period
b) Late auto - ignition
c) Low compression ratio
d) High self-ignition temperature of fuel
The most effective air cleaner in case of diesel engine is-
a) Dry type
b) Wet type
c) Whirl type
d) Oil bath type
Preferred location of an oil cooler is-
a) Before the filters
b) After the filters
c) Between the filters
d) Anywhere
High sulphur content in diesel oil used for diesel engines lead to-
a) Production of highly corrosive gases corroding the cylinder walls and exhaust system
b) Excessive engine wear
c) Damaging of both the storage tank and the engine
d) Reduction in thermal efficiency
The device used to reduce exhaust noise is called
a) Muffler
b) Exhaust pipe
c) Exhaust manifold
d) Tail pipe
The device for smoothing out the power impulses from the engine is called
a) Flywheel
b. Camshaft
c. Crankshaft
d. Clutch
Coolant temperature sensor is a thermostat or give information of temperature to
a) Fuel tank
b) Injection pump
c) E.C.M
d) Injector
Actually engine speed sensor indicates position of the
a) Camshaft
b) Crankshaft
c) Valve
d) Piston
Oxygen sensor is mounted on
a) Exhaust manifold
b) Intake manifold
c) Both a & b
d) None of these
Actuator is a type of sources.. .
a) Electro mechanic
b) Hydraulic
c) Only mechanical
d) Only chemical
In charging system - Alternator, which of the following is used to convert AC to DC in Alternator-
a) Slip rings
b) Diodes
c) Regulator
d) Starter
Clutch assembly are fitted with
a) Piston
b) Crankshaft
c) Gear box
d) Flywheel
Which method is used for oil supply to parts after filter?
a) Splash system
b) Full flow lubrication system
c) Splash cum pump method
d) Fly wheel splash method
If thermostat valve is closed, what will happen?
a) Engine do not run
b) Engine become hot gradually
c) Engine become vibrate.
d) Enginc bccomc very hot
Injection pressure in a diesel engine is about-
a) 10 bar
b) 100 bar
c) 150 bar
d) 500 bar
Which type of bearing is used for main bearing and connecting rod bearing?
a) Ball bearing
b) Needle roller bearing
c) Plain bearing
d) Taper roller bearing
Starter Motor, the engine crankshaft must be rotated at a speed of 100 rpm to start the engine. What is possible cause of the pinion disengages slowly after starting?
a) Weak battery
b) Over running clutch defective
c) Open in control circuit
d) Open circuit in commutator
The Firing order in an l.c Engine depend upon -
a) Arrangement of cylinder
b) Design of crankshaft
c) Noe of cylinder
d) All of these
Which component convert up & down motion in to rotary motion of piston is called
a) Camshaft
b) Crankshaft
c) Connecting rod
d) Piston rings
When air transmit to engine by turbo charger, what will happen?
a) Transmit exhaust gases
b) Transmit increased air pressure
c) Make Vacuum
d) Less air pressure
The impeller type exhauster has
a) One spindle
b) Two spindle
c) Three spindle
d) No spindle
The pressure of pump in common rail diesel injection system is
a) 10 to 10000 pound / square inch
b) 200 to 300 pound / squarc inch
c) 400 to 800 pound / square inch
d) 700 to pound / square inch
Which factor contribute to high fuel consumption?
a) Defect in Solenoid switch
b) Discharged battery
c) Clogged air cleaner-
d) Weak pressure relief valve
Lubrication oil consumption is high on a vehicle. Identify the cause
a) Breath filler removed
b) Battery is weak
c) Worn out piston rings
d) Alternator not charging
The ignition quality of diesel oil is expressed by-
a) Calorific value
b) Octane number
c) Cetane number
d) None of these
The thermal efficiency of diesel engine is about-
a) 15%
Which are following component used for oil pump run?
a. Crankshaft
b. Dammer pulley
c. Piston pin
d. Cam shaft
In engine specification it is given that cubic capacity is engine's
a) 'Lubricating oil capacity is 1.6 lit.
b) One cylinder total volume is 1.6 lit.
c) All cylinders sweep volume 1.6 lit.
d) Cooling water circulation per minute is 1.6 lit.
Cylinder head accommodates
a) Valves and injectors
b) Crankshaft
c) Cylinders liners
d) Connecting Rods
Tachometer in a vehicle measures-
a) Speed
b) Distance
c) Engine rpm
d) Fuel consumption
1.6 lit. it means the
The part which must be fitted in the piston to assure a good seal with cylinder wall is
a) Piston pins
b) Piston rings
c) Connecting rod
d) Gaskets
In which working cycle is completed in four stroke engine?
a) One revolution of the crankshaft
b) Two revolution of the crankshaft
c) Three revolution of the crankshaft
d) Four revolution of the crankshaft
In which parts are to be joined between cylinder head and engine block?
a) Valve guide
b) Compressor ring
c) Combustion chamber
d) Head gasket
A two stroke cycle engine gives the number of power strokes as compared to the four stroke cycle engine at the same engine speed.
a) Half
b) Same
c) Double
d) Four times
A two stroke cycle engine gives mechanical efficiency than a four stroke cycle engine-
a) Higher
b) Inwer
c) Same
d) None of these
After fitting rings over piston, it is inserted in cylinder with the help of a special tool called-
a) Ring Expander
b) Ring cleaner
c) Ring compressor
d) Ring groove cleaner
Compression ratio of diesel engine is- -
a) The ratio of volumes of air in cylinder before compression stroke and after compression stroke
b) Volume displaced by piston per stroke and clearance volume in cylinder
c) Swept volume/Cylinder volume
d) Cylinder volume/Swept volume
The main function of intake manifold is
a) Reduce intake noise
b) Provide the mixture of air and fuel
c) Distribute intake air equally to the cylinder
d) Cools the intake air to a suitable temperature
The heat transfer from coolant to air in radiator of an automobile engine take place by-
a) Radiation only
b) Convention only
c) Convention & Radiation only
d) Conduction, Convention & Radiation
Water circulation in a radiator take place from
a) Lower tank to upper tank
b) Upper to lower tank
c) Engine to upper tank
d) Engine to water pump
Supercharger is the function of-
a) Supplying the intake of an engine with air at a density greater than the density of the surrounding atmosphere
b) Providing forced cooling air
c) Supplying compressed air to remove combustion products only
d) Injecting excess fuel for raising more load
In case of gas turbines, the gaseous fuel consumption guarantees are based on-
a) Low heat value
b) High heat value
c) Calorific value
d) Net calorific value
Engine pistons are usually made of aluminium alloy because it.
a) Is lighter
b) Warless
c) Absorb shocks
d) Does not react fuel & lubricant oil
Which is more viscous lubricant oil?
a) SAE 30
b) SAE 40
c) SAE 50
d) SAE 80
In the opposed piston diesel engine, the combustion chamber is located -
a) Above the piston
b) Below the piston
c) Between the piston
d) Anywhere
Piston rings are usually made of-
a) Cat iron
b) Cast steel
c) Aluminium
d) Brass
The forced fed lubrication system means that the oil is delivered to the engine by-
a) Gravity b) The pressure created by the oil pump
c) Splashing action of the crankshaft d) None of these
Exhaust pipes of engines are covered with insulating material in order to
a) Keep the exhaust pipes warm b) Increase engine efficiency
c) Reduce heat transfer to engine room
d) Conserve heat
Fuel consumption with increase in "back pressure" will-
a) Increase
b) Decrease
c) Depend on the factor
d) Remain unaffected
In which parts of battery charging rotates crank fan belt?
a) Water pump pulley
b) Dynamo
c) Self Starter
d) Magneto
In order to eliminate knocking in compression ignition engines, there should be-
a) Short delay period
b) Late auto - ignition
c) Low compression ratio
d) High self-ignition temperature of fuel
The most effective air cleaner in case of diesel engine is-
a) Dry type
b) Wet type
c) Whirl type
d) Oil bath type
Preferred location of an oil cooler is-
a) Before the filters
b) After the filters
c) Between the filters
d) Anywhere
High sulphur content in diesel oil used for diesel engines lead to-
a) Production of highly corrosive gases corroding the cylinder walls and exhaust system
b) Excessive engine wear
c) Damaging of both the storage tank and the engine
d) Reduction in thermal efficiency
The device used to reduce exhaust noise is called
a) Muffler
b) Exhaust pipe
c) Exhaust manifold
d) Tail pipe
The device for smoothing out the power impulses from the engine is called
a) Flywheel
b. Camshaft
c. Crankshaft
d. Clutch
Coolant temperature sensor is a thermostat or give information of temperature to
a) Fuel tank
b) Injection pump
c) E.C.M
d) Injector
Actually engine speed sensor indicates position of the
a) Camshaft
b) Crankshaft
c) Valve
d) Piston
Oxygen sensor is mounted on
a) Exhaust manifold
b) Intake manifold
c) Both a & b
d) None of these
Actuator is a type of sources.. .
a) Electro mechanic
b) Hydraulic
c) Only mechanical
d) Only chemical
In charging system - Alternator, which of the following is used to convert AC to DC in Alternator-
a) Slip rings
b) Diodes
c) Regulator
d) Starter
Clutch assembly are fitted with
a) Piston
b) Crankshaft
c) Gear box
d) Flywheel
Which method is used for oil supply to parts after filter?
a) Splash system
b) Full flow lubrication system
c) Splash cum pump method
d) Fly wheel splash method
If thermostat valve is closed, what will happen?
a) Engine do not run
b) Engine become hot gradually
c) Engine become vibrate.
d) Enginc bccomc very hot
Injection pressure in a diesel engine is about-
a) 10 bar
b) 100 bar
c) 150 bar
d) 500 bar
Which type of bearing is used for main bearing and connecting rod bearing?
a) Ball bearing
b) Needle roller bearing
c) Plain bearing
d) Taper roller bearing
Starter Motor, the engine crankshaft must be rotated at a speed of 100 rpm to start the engine. What is possible cause of the pinion disengages slowly after starting?
a) Weak battery
b) Over running clutch defective
c) Open in control circuit
d) Open circuit in commutator
The Firing order in an l.c Engine depend upon -
a) Arrangement of cylinder
b) Design of crankshaft
c) Noe of cylinder
d) All of these
Which component convert up & down motion in to rotary motion of piston is called
a) Camshaft
b) Crankshaft
c) Connecting rod
d) Piston rings
When air transmit to engine by turbo charger, what will happen?
a) Transmit exhaust gases
b) Transmit increased air pressure
c) Make Vacuum
d) Less air pressure
The impeller type exhauster has
a) One spindle
b) Two spindle
c) Three spindle
d) No spindle
The pressure of pump in common rail diesel injection system is
a) 10 to 10000 pound / square inch
b) 200 to 300 pound / squarc inch
c) 400 to 800 pound / square inch
d) 700 to pound / square inch
Which factor contribute to high fuel consumption?
a) Defect in Solenoid switch
b) Discharged battery
c) Clogged air cleaner-
d) Weak pressure relief valve
Lubrication oil consumption is high on a vehicle. Identify the cause
a) Breath filler removed
b) Battery is weak
c) Worn out piston rings
d) Alternator not charging
The ignition quality of diesel oil is expressed by-
a) Calorific value
b) Octane number
c) Cetane number
d) None of these
The thermal efficiency of diesel engine is about-
a) 15%
Which are following component used for oil pump run?
a. Crankshaft
b. Dammer pulley
c. Piston pin
d. Cam shaft
In engine specification it is given that cubic capacity is engine's
a) 'Lubricating oil capacity is 1.6 lit.
b) One cylinder total volume is 1.6 lit.
c) All cylinders sweep volume 1.6 lit.
d) Cooling water circulation per minute is 1.6 lit.
Cylinder head accommodates
a) Valves and injectors
b) Crankshaft
c) Cylinders liners
d) Connecting Rods
Tachometer in a vehicle measures-
a) Speed
b) Distance
c) Engine rpm
d) Fuel consumption
1.6 lit. it means the
The part which must be fitted in the piston to assure a good seal with cylinder wall is
a) Piston pins
b) Piston rings
c) Connecting rod
d) Gaskets