well my fishing boats craps out on me & now I have some problems with my play boat - heres my symptoms, any help is greatly appreciated.<br /><br /> 1991 merc 3.0 - low hours.<br /><br /> Towards the end of the season last year I started hearing a scraping or clacking noise when I start the boat or at low RPMS, If I rev the motor & bring it back down to idle quickly the noise will go away for some time but may come back @ random. I did a search here & was convinced it was my "flapper" valve. I have replaced my flapper (which was worn) & still have this noise. The noise seems to come from the starter/bellhousing area or somewhere on the aft-starboard side of the motor. It will normally only last for 5 or ten secs so it really hard to get a stethescope on the problem area. Along with this noise I have a tiny tiny bit of blueish smoke comming out of the exhaust, slight smell of gas in oil - although my oil level does not increase, & if the motor has been worked hard (tubbing & skiing) for a while it will ociasionally diesel. The motor still runs strong & starts easily.<br /><br /> The dieseling doesn't concern me, I realize that this is a common problem on these 3.0's & a few minutes of idle be for shutting it off will solve that problem. The tiny bit of smoke doesn't really bother me either. My concern is this noise that I'm hearing. I plan to get it to a mechanic in the next week or two, but would like to take it out for atleast one more outing before I do so. Anyone have any ideas what the sound could be & is if a DIY project. FYI I have rebuilt 2 automotive engines. <br /><br /> Thanks again,<br /> TC
