Question 103Motor Plants - 1st Asst/Chief

The correct answer is D) Incompatibility of the fuels resulting in asphaltenes of the residual fuel precipitating out. The reason this is the correct answer is that when transitioning from residual fuel to distillate fuel, the change in fuel composition can cause the asphaltenes (heavy hydrocarbon compounds) present in the residual fuel to precipitate out and clog the final fuel filters. This is because the distillate fuel is less compatible with the asphaltenes, leading to their separation and eventual blockage of the filters. The other options are incorrect because they do not directly explain the clogging of the final fuel filters during the fuel changeover. Gasification of the fuel, carbonization of the cylinder oil, and stratification of the fuel in the mixing tank are not the primary causes of the filter clogging issue in this scenario.