Automobile Engine Fuel Pump

Fuel pump or also known as the Fuel Pump is one of the components in the fuel system on a vehicle or other internal combustion engines. Most machines require no fuel pump because of its design and with gravity, fuel will flow by itself in the fuel system. Most of the others had to use pumps to drain the fuel from the fuel tank. In using a carburetor engine, generally using low-pressure mechanical pump mounted outside the fuel tank while the engine with fuel injection, most have 2 kinds of pumps in the fuel delivery system, 

Medium pressure fuel pump / large volume in the tank or better known as the Fuel Pump. This pump is used to supply the needs of the fuel injection system. Generally electric pump mounted inside the fuel tank. 

High pressure pump / low volume or better known as the Fuel Injection Pump (FIP). This pump is in the fuel injection system material serves to pump fuel at high pressure to supply to the injector. 

Most of the engine with fuel injection does not have a fuel pump. Fuel injection systems suck fuel directly from the tank or FIP pumping fuel from the tank to the injector. 

Fuel pump has two types: 

- Mechanical fuel pump. 

- Electric fuel pump.

Mechanical fuel pump 

Design 

Most of this type of pump is a pump-type membrane. Membrane pump has a pump chamber whose volume depends on the elasticity of the membrane movement. In addition, it is equipped with one-way valve at the inlet and outlet. Specific designs vary widely, generally pump is mounted on the engine block or cylinder head. A shaft which has eccentric shaft and connected to the engine rotation will move the lever on the pump (directly or through a pressure shaft / connecting) membrane to move up or down motion. This movement will make the pump chamber volume will be larger or smaller, and repeated according to engine speed. When the pump chamber volume decreases, the pump chamber pressure will rise and result in one-way valve at the outlet is open and one-way valve at the inlet is closed, fuel is going to be pumped out through the outlet. When changing the volume of the pumping chamber of the smallest becoming enlarged, the pump pressure will decrease and result in one-way valve at the outlet closed and one-way valve at the inlet open, steel material will be sucked into the pump chamber through the inlet. When this process occurs continuously, fuel will flow from the tank to the carburetor or fuel injection system. Mechanical fuel pump pressure generally results in no more than 15 psi, qualified as a low pressure pump. 

Application 

Most of the gasoline engine with a carburetor and a small diesel engine uses a mechanical fuel pump

Electric fuel pump 

Electric fuel pumps are generally mounted on the fuel tank, a pump is installed in a small part of the engine room. Depending on the design, this type of pump produces pressure varies, from a low-pressure pump up high enough. Partially equipped with sensors to detect the load (supply) excess, which will turn off the pump work because generally there is no channel to flow back to the fuel tank. 

application 

Modern vehicles especially those already using a fuel injection system, generally using electric fuel pump because: 

Easier synergized with other systems, such as the electronic control unit. 

Injection pump will work more effectively if the incoming fuel injection pump in pressurized circumstances sufficient.