JFET_V5_N2_RP9 R. Ragu G. Ramadoss Sukumar Puhan V. Edwin Geo Journal on Future Engineering and Technology 2230 – 7184 5 2 64 69 Jatropha Oil Methyl Ester (JOME), Environmental Pollution, Alternative Fuels, Fossil Fuels Jatropha oil is one of the vegetable oils that has potential for use as fuel for diesel engines. But at room temperature (30-32 degree C) Jatropha has a viscosity about 10 times higher than that of diesel. To lower viscosity to the level of diesel's viscosity, a heating temperature of at least 180 degree C is needed. At this temperature, there is a concern that the close-fitting parts of the injection system might be affected. This study focused on finding out the effects of preheating of fuel on the performance and emissions of a DI diesel engine. Results show that preheating of Jatropha oil lowered emissions compared to Jatropha oil. However, heating is necessary for smooth flow and to avoid fuel filter clogging. Both can be achieved by heating Jatropha oil to 180 degree C. Over the entire load range, preheated Jatropha oil combustion produced lower CO and HC emissions that were 30 % and 25 % compared to Jatropha oil. NO emission is higher about 5% in the X case of preheated oil compared to Jatropha oil. November 2009 - January 2010 Copyright © 2010 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=1100