Mechanical and Automobile Engineering Interview Questions

Automobile engineering is the branch of mechanical engineering which deals with auto movable vehicle. In this article here are the interview and questions for new jobs as well as viva of experiments.Here are the question based on the topics like gear box, ignition system, lubrication system,suspension system, fuel supply system, steering system and breaking system etc..

Q. 1 What is the principle of gearing?

Ans. The ratio of speeds of the two gears is inversely proportional to the ratios of the number of teeth on each gear.

Q. 2 What are the advantages of constant mesh gearbox over sliding mesh gearbox?

Ans. In constant mesh gearbox, the gear engagement is quick, quieter and smooth.

Q. 3 What is double-declutching in the synchromesh gearbox?

Ans. During the gear change, the driver needs to disengage the clutch twice in a very quick time, so it is called as double-declutching.

Q. 4 How the hydrostatic propulsion systems work in the tractor?

Ans. Hydrostatic propulsion system works according to Pascal's law. But on the piston of tractor's engine pressure is same. Hence this pressure is divided according to the area. Like more force in a large area and less force in a small area.

Q. 1 What is an oil breather?

Ans. The oil breather is an opening in the engine lubricating system,through which oil is exposed to the surrounding.

Q. 2 What is the purpose of lubrication?

Ans. The purpose of lubrication is to cool,clean,avoid wear and forming a kind of seal in the parts.

Q. 3 What is the delivery pressure of oil pumps?

Ans. 2.5 to 4.5 kg/cm2

Q 4 What would happen If someone will add lubricating oil to the fuel of a bike?

Ans. The physical properties of lubricating oil are different from the fuel oil. Hence as a result the engine will go to the soon damaging. There will be more wear and tear in the piston and linear. There will be some knocking also. Knocking will reduce the efficiency and breakpower of the engine.

Questions on Suspension System

Q.1 What is steering ratio and what is its normal value?

Ans. It is the ratio between rotation of steering wheel to rotation of steering gear that connects the drop arm. Its value lies between 15 to 35.

Q. 2 What type of steering gear is used on maruti 800?

Ans. Rack and pinion steering gear.

Q.3 What is the turning radius for small cars?

Ans. It is 8 to 10 meter.

Q 4. What is the reason of car wandering?

Ans. The reason of car wandering or may be bent king-pin,too light ball joint, or uneven tyre pressure.

Q. 1 What are the requirements of efficient breaking system?

Ans. The breaking system that stop the vehicle within the smallest distance is called efficient breaking. It is used to sop the vehicle and to control the speed during operation.

Q .2 What are the advantages of hydraulic breaking system?

Ans. Hydraulic breaking requires less breaking effort, and breaking effort is equal to all four wheels.

Q. 3 What is the working principle of hydraulic break?

Ans. Pascal's law.

Q. 4 What is Pascal law?

Ans. If we apply pressure at a point in the fluid then it transfer it in all the direction equally.

Q. 5 Why does break overheat sometimes?

Ans. Breaks overheat due to jammed break shoes or prolonged use of break.

Q. 1 Among the Matiz,Satro,and Indica cars Which has 3 cylinders?

Ans. Matiz.

Q. 2 Among the above cars whose capacity is maximum and and how much is its value?

Ans. Indica, 1598cc.

Q.3 Among the above which car has 3 valves per cylinder?

Ans. Santro.

Q. 4 What is the kerb weight and payload of a TVS scooty?

Ans. 81.5 kg and 130 kg respectively.

Q. 5 What is the capacity of Maruti 800 engine?

Ans. 796 cc.

Q. 1 What were the problems in simple carburetor?

Ans. 1 Less volumetric efficiency.

2 Mal distribution of air fuel mixture in multi cylinder engine.

3 Ice Forming

4 Problem in turning due to tilting of carburetor.

Q.2 What are the three sub systems of electronic fuel injector?

Ans. 1 Fuel delivery system, 2 Air induction System, 3 Electronic control unit.

Q. 3 What are the main components of automobiles?

Ans. 1 Engine,2 Clutch,3 Gear box,4 Universal Joint,5 Propeller Shaft,6 Differentiator.

Q. 4 Why maintenance is required in automobiles?

Ans. 1 Safety of automobiles,2 Reliability of the automobiles,3 Lognitivity of the automobiles,4 Comfortable driving of automobile.

Q. 5 What are the type of lubrication systems?

Ans. 1 Petrol Lubrication system, 2 Scrap feel system, 3 Forced feed lubrication system, 4 Combination of scraps and forced feed system

Q.6 What are the type of fuel injection system in CI engines?

Ans. 1 Air Injection System, 2 Airless Injection System. ( a Common rey injection system,b Individual Pump injection system.

Q.7 What is a master leaf in suspension system?

Ans. The uppermost longest leaf having bushes at its two ends, is known as master leaf.

Q. 8 What is the material of leaf spring?

Ans. Leaf springs are made of

1 medium carbon steel about 0.55 % C,

2 Silicon alloy steel having about 2%Si,1%Mn and

3 Chrome manganese vanadium alloy steel having about 1.5% Cr, 0.6% Mn, and 0.2% V.

Q. 9 How power is generated in the cylinder of IC engine?

Ans. Air is sucked during the crank motion and on compression stroke fuel is injected on it by the nozzle and the automization and vapourisation takes place. Now at proper temperature and pressure this air and fuel mixture starts burning and the chemical energy of the mixture is converted into pressure energy and this pressure energy pushed the piston and hence mechanical power is generated by the piston movement.