For a practical petrol engine working on otto cycle , the compression ratio usually lies in the range
3-5
6-8
10-15
16-22
Which is a false statement in the context of the parts of an I.C. engine?
The piston is connected to the small end of connecting rod by a gudgeon pin
Crank pin connects the big end of connecting rod to crank arm
The reciprocating motion of the piston is converted to the rotary motion by the connecting rod and crank mechanism
The crankshaft provides the power and direction to the suction and exhaust valves
Accumulation of carbon deposits on the cylinder head of an I.C. engine leads to increase in
Clearance volume
Swept volume
Piston displacement
Compression ratio
What is the main shaft of an engine that controls the movement of piston?
Axle
Drive shaft
Crankshaft
Camshaft
What is mounted on the crankshaft to transform rotary motion into back-and-forth motion for actuating the valves?
Crank
Crank and slider
Camshaft
Flywheel
In four stroke engines, the camshaft is connected to the crankshaft by gears or chain and rotates at
Half the crankshaft speed
Three-fourth the crankshaft speed
Equal the crankshaft speed
Double the crankshaft speed
In four stroke engines, the camshaft gear has
Half the teeth on the crankshaft gear
Equal the teeth on crankshaft gear
Twice the teeth on crankshaft gear
Four times the teeth on crankshaft gear.
Consider the following statements:
The injector nozzle of a CI engine is required to inject fuel at sufficiently high pressure in order to
be able to inject fuel in a chamber of high pressure at the end of the compression stroke
inject fuel at high velocity to faciliatate atomization
to ensure that penetration is not high
Which of the above statements are correct?
1 and 2
1 and 3
2 and 3
1,2 and 3
Generally, in bosch type fuel injection pumps, the quantity of fuel is increased or decreased with change in load, due to change in
Timing of starts of fuel injection
Timing in end of fuel injection
Injection pressure of fuel
Velocity of flow of fuel
In diesel engines, the injection pressure is of the order of
50-80 kgf/cm2
100-150 kgf/cm2
175-250 kgf/cm2
400-500 kgf/cm2
What would be the probable reason of power loss in a diesel engine?
Clogging of air cleaner
Restricted exhaust
Low injection pressure
Ineffective cooling
The term air injection, associated with fuel injection system of an I.C. engine means injection of
Air only
Liquid fuel only
Liquid fuel and air
Solid fuel and air
The calorific value of diesel fuel is about
7500 kcal/kg
8200 kcal/kg
10000 kcal/kg
12500 kcal/kg
The ignition temperature of diesel fuel is about
250oC
400oC
600oC
750oC
A normal diesel engine will need minimum changes if made to run on
Petrol
Kerosene
Alcohol
Ammonia
When a petrol engine is supplied with diesel fuel,
The engine will not run
The engine will consume more fuel
The engine will operate with reduced output
The exhaust will have dense black smoke
The process of augmenting the engine power by raising the pressure of charge, fed into the engine cylinder, is called
Scavenging
Supercharging
Pumping
Doping
Supercharging is the process of
Providing a draft of air for cooling purposes
Supplying air to remove the spent up gases
Raising the pressure of charge fed to the cylinder
Supplying more fuel for getting greater output
An engine is supercharged essentially for
Fuel economy
Increased efficiency
Knock free engine performance
Reduced weight and bulk of the engine for a given output
The control gear to epicylic gear unit is called
Planet gear
Sun gear
Ring gear
Internal gear