The continuous world-wide tendency to increase engine performance and reduce emissions has necessitated the development of new generations of enhanced diesel fuel injection equipment, supporting the achievement of stringent legislation targets. Rising injection pressures and multiple injections result in higher operating temperatures, increased contact pressures and reduced clearances. Minimum standards of fuel quality are essential to maintain durability and emission compliance over a longer duration.

International standards have been established defining fuel quality and continue to be revised on an as needed basis. Alterations to fuel quality, e.g. by increasingly severe refinery hydro-processing being introduced to remove sulphur also reduce the content of aromatics and destroy surface active compounds and antioxidants. Removal of these beneficial compounds effects boundary lubrication, commonly known as lubricity, and inherent oxidation stability and must be compensated for. Fuel parameters such as cetane number, viscosity, density, lubricity, oxidation stability, sulphur and aromatic content together with the absence of free water and dirt contamination are key parameters required to ensure performance of equipment in the field.

Biofuels are becoming increasingly available to end-users. In Europe (EU) and in the United States of America (USA), as well as in other countries, fuel sources such as rapeseed methyl ester (RME), soybean methyl ester (SME), palm oil methyl ester (PME) and others, collectively known as fatty acid methyl esters (FAME), are being used as alternatives and extenders for mineral oil derived fuels. Furthermore, the EU Biofuels Directive 2003/30/EC requires member states to ensure that a minimum proportion of biofuels are placed on the market. It must be recognized that the physical and chemical characteristics of bio components are significantly different to conventional fuels and that care must be taken in their specification and use.

Diesel fuel injection equipment (FIE) manufacturers fully support the development of alternative sources of fuel. Where possible, compatible components were provided and validated. However, many vehicles, engines and equipment are not designed to run on them. It is recommended to refer to the vehicle and engine manufacturers ‘Limitations of Use’ documents for guidance. Prior to use, users should also check whether appropriate biofuel quality is guaranteed. 

Signatories to this statement are Delphi, Bosch, Denso, Continental and Stanadyne  READ MORE