Fuel pumps

The purpose of a fuel pump is to supply the engine with a greater amount of fuel than it needs. The pump is mounted either inside the fuel tank or outside the tank. Today, internal petrol pumps are available that are highly efficient and can deliver up to, for example, 1000 hp. Fuel pumps are nowadays electrically powered by a 12-volt supply through a relay, which is activated by the engine management when the engine is running. The fuel is carried up to the engine’s fuel rail through fuel hoses, so it is important to choose hoses that are large enough to deliver the amount of fuel the engine needs. Once the fuel has passed through the fuel rail, it is sent into the fuel pressure regulator, which controls the base pressure, and then returned to the tank through another fuel hose. Be careful not to choose a hose that is too small, so the regulator can release the required amount.

A fuel pump becomes worn and deteriorates over time and with use. Often around the 200,000-kilometre mark, you should pay attention to the petrol pump, and this is not always something that can be noticed during everyday driving. If the pressure drops under peak load, the air-fuel ratio becomes lean, and under prolonged load it can melt a piston in the engine, which is expensive to replace, if not the entire engine ends up needing replacement. If dirt gets into the tank, the fuel pump can very quickly deteriorate and need to be replaced, so it is important to empty and clean the tank.

Replacing a fuel pump is often something you can do yourself, as long as you have some basic tools. If the fuel pump is located in the tank, you can often access it by removing the rear seats in the car, unscrewing a cover and unscrewing the lid down to the pump. Lift out the fuel pump assembly and replace the pump. It is recommended to replace the flex hose located between the pump and the top cover, as this is often damaged when removing it. Afterwards, it is simply a matter of reassembling everything in reverse order. It can take between 30 minutes and 4-5 hours depending on whether the tank has to be removed to access the internal fuel pump.

Power in hp at 3 bar base pressure:

For cars with an internal petrol pump, models such as Wallbro GSS 340, 341 and 342 can be a good choice. They are known for being relatively easy to install, partly because they are compact in size and therefore fit well in many tanks and pump setups. The difference between the models mainly lies in the position of the outlet, which is either centred or offset to one side, so it is important to choose the variant that best suits the specific installation.

If you instead need an external fuel pump, the Bosch 044 is a classic and popular solution for tuning, motorsport and other performance projects. It is used in many upgraded fuel systems where a stable and reliable external pump with good capacity is required. When installing an external petrol pump, it can also be an advantage to use a suitable fuel pump bracket so that the pump is mounted correctly and securely in the system.