This is the device that takes fuel from the fuel tank and delivers it as per the demands of the engine. So the fuel is drawn from the tank and propelled into the internal combustion engine through the fuel pump. If the fuel pump is working effectively, the car will run properly.
Mechanical Fuel Pumps
Before the extensive adoption of electronic fuel injection, most of the carburetted automotive engines had mechanical fuel pumps that are also known as “puller pumps”. These had a good suction ability and transferred fuel (petrol or diesel) from the fuel tank to the fuel bowls of the carburettor. The space between the pump and the carburettor is fairly short and therefore puller pumps do not need to work hard to maintain a good …show more content…
The electric pump is located in the fuel tank itself and creates positive pressure in the fuel lines to push the fuel to the engine. The higher fuel pressure increases the boiling point. Placing the pump in the tank puts the unit least likely to handle the fuel vapour well (the tank) farthest from the engine, submerged in cool liquid. Another advantage of placing the pump in the tank is that it will not start a fire. While the electrical components can spark and ignite fuel vapours, liquid fuel does not explode up to a limit and so submersing the pump in the tank is one of the best places to put it in. In most of the cars, the fuel pump sends a constant flow of fuel to the engine and the fuel not used is returned to the tank. This too reduces the possibilities of the fuel boiling as it is never kept close to the engine for very …show more content…
This causes a dramatic increase in hydrocarbon (HC) emissions. A car that experiences this kind of problem may not pass an enhanced emissions test.
Accelerated wear may also happen if debris or rust gets past the inlet filter sock. In some cases a pump will fail if contaminants enter and jam it, causing over heating for the motor and burning it out. In another case, a weak fuel pump or one that cannot generate adequate pressure can disturb the calibration of the fuel system. This can cause the engine to run in a weak manner or it may starve for fuel under load. The symptoms then include difficulty in starting the car, deteriorated ride quality, hesitation in acceleration and loss of high-speed power.
As electric fuel pumps run constantly, they may experience wear in the amature bushings, brushes and commutator after many years of service. Pump vanes, rollers or gears can also wear and cause a gradual loss of pressure and flow.
The Right Strategy
You should ideally have at least a quarter of the tank filled with fuel instead of totally emptying it fully before a refill. Low fuel levels largely make the fuel pump work harder and can then contribute to its