What are the problems related to long-term fuel storage?
Temperature, humidity, and condensation are very important factors to consider in managing fuel quality. The presence of free water provides the medium for microbiological growth, resulting in the formation of slime or acids that can cause corrosion of metal surfaces; such as storage tanks, pumps, injectors, etc.
Other key factors leading to fuel deterioration, polymerization, and stratification within storage tanks are chemical incompatibility and stress caused by heat and pressure from pumps, centrifuges, and heaters. Since most diesel engines return considerable amounts of fuel back to the tank (due to fuel not being completely used during the combustion process), it is easy to see that the engine itself contributes to fuel deterioration.