I am a new arrival to boating ,and I was offered a 16.5Ft speedboat with a 115hp yamaha v4. I was told the engine was late eighties or early ninties but I have my doubts. the engine is flatter and fatter than other Yam v4s and the powerhead is coloured mid metallic blue (not the later darker blue. THe decals are white and are stickers though there is a chrome or plastic badge on the back saying 'V4',. It looks really clean and has been rebuilt but the design and colour suggests seventies not Eighties. Can anyone help before I buy a 'lemon'<br />Thanks