How does my engine negatively impact fuel quality?
A diesel engine uses only some of the fuel it pulls from the tank. All fuel pulled from the tank goes through the high-pressure fuel pump and the injectors which operate under very high pressure and temperature.
The surplus fuel the engine does not use goes back to the tank. This fuel is continuously re-circulated and exposed to extreme pressure and heat, which results in the agglomeration of asphaltenes, which are high carbon content, heavy end fuel molecules. It leads to the formation of larger and larger clusters and solids, which are very difficult to completely combust. These solids may grow so large that they will not pass through the filter element and become part of the polymer and sludge build up plugging the filter.
In addition, the hot fuel coming back to the tank will raise the fuel temperature in the tank, cause condensation and contribute to microbial contamination, fuel break down, bio fouling and the build up of sludge and acid.
Large fuel droplets and high asphaltene concentrations require more time, more energy and higher temperatures to combust than is available during the combustion cycle.
Any device in the fuel system exposing the fuel to stress (heat and pressure) such as pumps, heaters, or centrifuges will increase the formation of asphaltenes and negatively impact combustion.