Many studies have been carried out on raw rapeseed oil (PPO) and its performance in a common rail diesel engine. In this study the PPO had characteristics within the DIN V 51605 norm. The engine, model 6068HL481 rated at 103 kW and installed in agriculture tractor John Dear 6830, was studied after working for 230 h and then for 1000 h. Full characteristic of the engine fueled with PPO was obtained for both tests and was then compared with the characteristic of the engine fueled with diesel. A power drop of 12-14% was observed in the engine fueled with PPO as opposed to the one fueled with diesel. The alternate fuel had no impact on the energy efficiency. (C) 2012 Elsevier Ltd. All rights reserved.