Do Cetane Improving Additives Really Improve Fuel Quality?
• Fuel quality is defined by the physical property specifications given in the ASTM Standard Specification for Diesel Fuel Oils, ASTM D-975. Carbon residue, ash and sulfur increase engine wear and deposit formation. Premium diesel fuels should have lower specifications of these properties. Additionally, premium diesel fuels should be more stable in storage than standard fuels, so the premium fuel quality you purchase won’t degrade over time. This is the area where nitrate-containing cetane improvers cause problems. • More fuel retailers are introducing premium diesel fuels, touting high cetane number as the sole benchmark of fuel quality. Contrary to his assumption, a cetane number which is too high may cause too short an ignition delay period. This changes the timing of the pressure peak, resulting i loss of power. When this happens, many of the performance problems associated with low cetane fuel will result. While the problems due to low cetane largely disappear after the engine war
