JP-8 Fuel Effects on High Pressure Common Rail Pumps

The Army uses JP-8 fuel for both its tactical and non-tactical, diesel powered vehicles. Some of the commercial engines used by the Army employ high pressure, common rail fuel injection systems to lower exhaust emissions, especially particulates. Modern common rail injection systems produce pressures of 1500 to 2200 bar. These systems are designed to run on ultra-low sulfur diesel fuel that contains special lubricity additives (usually fatty acids) to reduce wear and scuffing. JP-8 fuel does not contain these important additives. Therefore, to achieve acceptable fuel system life, special fuel filters have been devised that meter a lubricity additive to the fuel system. The use of these filters is undesirable from a field logistics perspective. We propose to eliminate the need for "lubricity filters" and additives by redesign of the common rail pump. We have developed materials pairs and other proprietary methods that significantly reduce the wear of high pressure common rail pumps. In phase 1, we propose to conduct a bench durability test on a common rail fuel pump (Cummins ISL) to define which components have unacceptable wear. We will then develop a design proposal that suggests changes to reduce wear without the use of fuel additives.