For the past few decades, research has scaled up in the development of environmental friendly alternative fuels such as biodiesel that can minimize the use of conventional fuel resources. The present study deals with the performance and emission characteristics of 60% crude pongamia oil with 40% diesel (DBD 1) and the results are compared with 100% conventional diesel on a single cylinder direct injection diesel engine without any modifications at full throttle condition. The study is extended further by adding 15% of orange oil to 60% crude pongamia oil and 25% diesel fuel (DBD 2). It is found that the addition of orange oil to the crude pongamia biodiesel blend have shown notable improvement in performance and reduction in emissions compared to crude pongamia diesel blend. The results indicate that the values of brake specific fuel consumption, brake thermal efficiency and mechanical efficiency obtained with the biodiesel blend (DBD 2) are very close and the emissions are less when compared to conventional diesel fuelled engine. From the study it is observed that DBD 2 can be used as an alternative fuel for conventional diesel in a direct injection diesel engine without any modifications.