Thursday, 18 April 2019

KNOW HOW A CAR ACCELERATES ?


Going from 0 to 60 mainly involves the throttle, engine, transmission or differential, and tires of a vehicle. How fast it takes depends on the features of these parts.When you hit the gas pedal/throttle on your vehicle, there are a number of forces at play to get it going. 

Here is a basic run-down of what happens when your vehicle accelerates.

1.)Throttle to engine

The throttle pedal/throttle is a direct line to your vehicle’s engine. It controls the airflow into the intake manifold either through a throttle body for fuel injection, or a carburetor. This air is then mixed with fuel, fed either by a fuel rail and fuel injectors, or a carburetor, and is then introduced with spark (such as fire), fed by spark plugs. This causes combustion, which forces the engine’s pistons down to rotate the crankshaft. As the throttle pedal gets closer to the floor(full throttlr in case of motorbikes), the more air is sucked into the intake manifold to be mixed with even more fuel to rotate the crankshaft faster. This is your engine “revving” as the revolutions per minute (rpm) of the crankshaft increase.

2.)Engine to transmission

If an engine’s crankshaft output shaft is not connected to anything, it will simply rev and make noise - not acceleration. This is where a transmission comes into play, as it helps transform engine speed into wheel speed. Regardless of whether you have a manual or an automatic transmission, both varieties tap into the engine via an input shaft. Sandwiched between the engine and the transmission is either a clutch for manual transmissions, or a torque converter for automatics. In essence, a clutch and engages the engine from the transmission, while a torque converter maintains the connection but uses a fluid-fed one-way stator and a turbine to eliminate engine stalling when idle. Think of it as a device that is constantly “slipping” the connection between the engine and the transmission.

And from transmission the motion goes to tyres in case of motorbikes through chain or belt and in case of cars, it will go to differential and from differential it will go to tyres.

Wednesday, 17 April 2019

DIFFERENCE BETWEEN GOVERNOR AND FLYWHEEL EXPLAINED !!


Both flywheel and governor are mechanical devices used mostly for the same purpose; that is to control or regulate the fluctuations in speed with the exception of the point of impact.While a flywheel regulates the variation of speed at crankshaft, governor controls the variation of speed caused by load variation.Let us first understand the applications of flywheel and governor and then we will come to differences.

FLYWHEEL:

A flywheel is a heavy rotating wheel attached to a revolving shaft that smooths out the delivery of power of a reciprocating engine due to the difference between the driving torque and the active torque over the cycle of operation.

Basically, it’s a mechanical device specifically designed to store rotational energy. It acts as a reservoir, meaning it stores energy when the supply of the energy is more than that is required for the operation and releases the same when the supply is less than the requirement.

GOVERNOR:

A governor is also a mechanical device that controls mean speed of the engine when there are variations in the load. 

It’s essentially a speed-controller device used to measure and regulate the speed of the machine irrespective of the load variations. It maintains the speed of the engine within specified limits regardless of load variations.

DIFFERENCE BETWEEN FLYWHEEL AND GOVERNOR:

SUMMARY:

While the function of a flywheel is to regulate the fluctuations of speed during each cycle, the function of a governor is to keep the mean speed of the engine constant throughout the entire cycle. Flywheel stores rotational energy when the mechanical energy supplied is more than that’s required for operation, whereas a governor regulates the fuel supply according to the varying load conditions. While hypothetically both serve the same purpose, that is speed control, they do it very differently. The main difference in fact lies in the point of impact.

Tuesday, 16 April 2019

KNOW THE REASON AND SOLUTION OF DIFFERENT EXHAUST SMOKE COLOURS !!


Exhaust smoke is a way of your car communicating with you to say what is wrong. Usually, the smoke that gets emitted is black, white, grey and blue. The exhaust gases is an old school way to detect symptoms of problems i.e. large amounts of black smoke may mean the EGR is blocked and it's over fueling.

Knowing the difference between the smokes that comes from the exhaust is very useful. If you are not going to fix the car yourself, take note when the smoke appears and the color and report back to your mechanic. Avoiding the problem will only shorten the life of the engine and result in unnecessary repair bills.

TYPES OF EXHAUST SMOKES
1. White smoke
2. Black smoke
3. Blue smoke

Let us discuss the reason for each type of smoke in detail:

1. WHITE SMOKE

Thick white smoke can be caused by the engine burning coolant. This can be caused by the coolant leaking into the engine due to a leak in the head gasket, a damaged cylinder head or a cracked engine block. If you happen to see this kind of smoke take your car to the garage as soon as possible as the leaking coolant can lead to overheating which could cause damage to your engine. Not to mention chances of coolant mixing with the oil.
White smoke has a varying amount of causes and symptoms, which are more common in gasoline cars. The most common cause of white smoke is when the car has just been started. The white smoke is just steam from condensation that clears as the car warms up.
White Smoke from Petrol/Gasoline Car
White smoke as mentioned is usual from startup however if it continues when warm, you have a problem. Check the following for white smoke causes in petrol cars:
a. Head Gasket Failure.
b. Turbo Issues
c. Overheating Engine.
d. Cracked Engine Block.


White Smoke from Diesel Car
Sadly, white smoke from a diesel car operating at its optimum temperature is bad news in most cases. Check for the following for white smoke in diesel cars:
a. Worn or Leaking Injectors.
b. Poor Quality Diesel.
c. Low Cylinder Compression.
Usually caused by other components such as piston rings becoming worn out

2. BLACK SMOKE

Black smoke that gets emitted from a car is more common in diesel cars. Apart from when the car is cold, white smoke should never appear from a diesel car exhaust. The majority of older diesel cars will blow black smoke under heavy acceleration but new diesel car will not emit any black smoke.This results in very poor miles per gallon and extra stress on engine components.

Petrol engines very rarely emit black smoke from the exhaust compared with diesel cars. In almost all circumstances, black smoke from a petrol car is due to the air to fuel ratio.
Black smoke from a diesel car is the result of poor combustion of the fuel. The issue is either due to insufficient air flow or poor quality diesel that builds up into a carbon deposit. Causes of black smokes from diesel car exhausts are the following:

a. Clogged Air Filters
b. Damaged Fuel Injectors
c. Faulty MAF (Mass Airflow Sensor)Sensors
d. Bad EGR Valve
e. Damaged Piston Rings
f. Engine Deposits
g. Poor Quality Diesel Fuel.
h. Faulty Turbocharger and Bad Air to Fuel Ratio.

3. BLUE SMOKE


Blue smoke is an indication that the car is burning engine oil. This happens when the piston rings are worn out and oil is leaking to the combustion chamber where it is burned together with the fuel. For a turbocharged car, the smoke is a sign that the blower is in need of replacement. Burning oil can cause rough starts due to the fact that it can ruin a car’s spark plugs.