Hello, i am new to boating and have yamaha 40 hp two stroke 3 cylinder oil injected possibly 2002 ? numbers on it are 6H4 4 OVETO L544784 U . motor starts and runs ok a bit rough and conks out often. i have several questions, how can i more accurately identify year and model, can i get service manual for this engine ? i wish too service this engine and gearbox myself and if easy enough decarbonise engine and clean carbies any tips on how too service and get this motor running sweet as i can would be appreciated. thanks b00tsyo42 in western australia