ABSTRACTThe present paper deals with the comparative study of performance and emission characteristics of a multicylinder (Indica) engine fueled with Manilkara zapota methyl ester (MZME), Karanja methyl ester (KME), and neat diesel. Twenty percent of both biodiesel, designated by MZME20 and KME20, were tested in engine to assess their performance at different engine speeds. The physicochemical properties of produced biodiesels (MZME and KME) were well within the ASTM/EN standard limits. The experimental results indicated increased brake-specific fuel consumption and decreased brake power for both the biodiesel blends than that of neat diesel operation. At full load conditions, CO and hydrocarbon (HC) emissions were found lower while NOx emissions were found higher for blended fuel in comparison to diesel fuel. Between the biodiesel-blended fuels, MZME20 indicated superior performance and least emission than KME20. Thus, from earlier study it can be concluded that 20% of M. zapota biodiesel can be used in a multicylinder diesel engine without doing any modification in existing engine.