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The correct timing of the diesel injection pump on engine is of major importance for all functions of the engine and for its exhaust emissions, during production pass off as well as in the field. Within the diesel service workshops a variety of devices exist to test the timing of the injection pump on engine. Most of them operate by clamp-on transducer being fitted to the injection pipe. A large uncertainty exists concerning the accuracy of such timing systems. Most diesel engine manufacturers do not have confidence in the timing devices capability and, therefore, do not recommend their usage. A working group within the International Organization for Standardization (ISO) adopted a method for the validation of these measurement systems, which usually is used to judge the capability of measurement gauges for industrial production processes.

A cooperative research and development program was organized to determine the critical particle size of abrasive debris that will cause significant wear in rotary injection fuel pumps. Various double-cut test dusts ranging from 0-5 to 10-20 μm were evaluated to determine which caused the pumps to fail. With the exception of the 0-5-μm test dust, all other test dust ranges evaluated caused failure in the rotary injection pumps. After preliminary testing, it was agreed that the 4-8-μm test dust would be used for further testing. Analysis revealed that the critical particle size causing significant wear is 6-7 μm. This is a smaller abrasive particle size than reported in previously published literature. A rotary injection pump evaluation methodology was developed. During actual operation, the fuel injection process creates a shock wave that propagates back up the fuel line to the fuel filter.

A working group of the International Organization of Standardization (ISO), in cooperation with the Coordinating European Council (CEC), has conducted a round robin test program to compare laboratory bench tests to evaluate the lubricity characteristics of diesel fuels. The goal of the ISO program was to generate sufficient data from these test methods and from fuel injection equipment performance tests to select a test method for determining diesel fuel lubricity. The ISO group also aimed to produce sufficient information to define a minimum lubricity level that would protect fuel delivery system components. Four laboratory test methods were included in the program. These consisted of Falex's Ball on Three Seats (BOTS), Lubrizol's Modified Ball-on-Cylinder Lubricity Evaluator (BOCLE), Paramins' High Frequency Reciprocating Rig (HFRR), and the U.S. Army's Scuffing Load BOCLE.