The BMD900 marine diesel engine has been designed and modified to be used in seagoing ships up to 840 horse power. Some merits of the engine upgrade are the design of heat exchangers, ECU, etc., and it can have constant torque in different engine operating periods and optimum performance in the Persian Gulf. The BMD900 marine engine is used in planning systems with a maximum of 15 meters and a maximum tonnage of 12 tons, and in semiplanning floating vessels with a maximum of 15 meters and a tonnage of 19 tons