2002 Merc 90 hp Burned bottom piston

[wjefcoat]

I previously posted saying I rebuilt my carbs and on the next trip to the water burnt a hole in the lower piston. I had the block bored and my parts will be in today. Everyone suggests that carb was running lean but when I took it apart it looked brand new and the bowl was full of gas just like it should have been. I also ordered a service manual so im pretty confident I will have everything just right. Does anyone out there have any suggestions so that this doesn't happen again?

 

[beckerjs]

Re: 2002 Merc 90 Burned bottom piston

blow air through the main jet on that carb and verify its free and clean, check the reed valves to make sure there not stuck, check the timing

 

[wjefcoat]

Re: 2002 Merc 90 Burned bottom piston

im really new to outboards, is it possible for just one cylinder to be out of time, also how do get the circlips in, already messed up two