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A technology demonstration program was conducted by the U.S. Army to verify the feasibility of using aviation turbine fuel JP-8 in all military diesel fuel-consuming ground vehicles and equipment (V/E). Over 2,800 pieces of military equipment participated in a two and one-half year program accumulating over 2,621,000 total miles (4,219,810 km) using JP-8 in combat/tracked, tactical/wheeled, and transportation motor pool vehicles. Over 71,000 hours of operation were accumulated in diesel/turbine engine-driven generator sets using JP-8 fuel. Comparisons of various performance areas with baseline diesel fuel (DF-2) operation were made.

This paper is the second of two that describe the effects of low-lubricity fuels on diesel injection pump performance. The first paper describes the primary failure mechanisms and wear processes in a number of failed pumps removed from both military and civilian vehicles that had been operated on Jet A-1 and diesel fuels. However, the multitude of unregulated parameters in practical operation renders quantitative comparison between different fuels and pump combinations impractical. This paper describes the degradation in pump performance and the wear processes associated with fuels of varying lubricity in the well-defined environment of a pump test stand. The test methodology concentrates on those areas previously demonstrated to be most susceptible to wear. The results indicate that pump durability is reduced by highly refined low-viscosity fuels, but may be successfully counteracted by either improved metallurgy or lubricity additives.

The U.S. Department of Defense has adopted a concept in which a single fuel will be used on the battlefield; diesel fuel will be replaced by JP-8/JP-5/Jet A-1 in compression ignition engines, thereby decreasing the fuel logistics burden. JP-8 fuel has successfully undergone extensive testing in both the laboratory and in field trials. However, increased failure rates for fuel-lubricated rotary injection pump components operating on Jet A-1 aviation turbine fuel were reported during Operation Desert Shield. This paper is the first of two and describes the disassembly and failure analysis of twelve rotary fuel injection pumps that operated on Jet A-1. Also disassembled as a baseline for comparison were three additional pumps from civilian vehicles that had operated on commercial diesel. Each of the pumps had a unique service history, making quantitative comparison difficult.