Mariner 115 won't stay running

[markthbdx]

First off I just want to apologize for my ignorance. I'm new to iboats, and by no means a mechanic. Now with that being said I have a mariner 115 (which I believe is a 93 or 92 model). It's the inline 4 cylinder. I was having trouble with it running rough. I took a look at it and found that the accelerator pump diaphragm was busted. I replaced the diaphragm and decided to go ahead and clean the carbs while I was at it. I also changed some fuel lines, cleaned the tank and replaced inline fuel filter. Now after I put everything back together it won't run at all. It will crank and run for a couple seconds and that's all(also smokes more than normal). I knew it had to be something I did with the carbs because it was running before. Through research I found a picture of a diagram of my carbs with a notation saying NOT to touch a set screw that was factory set! I realized at that time that I had broke that screw loose on the bottom carb. When I realized it was not something I wanted to mess with I had just tightened it up all the way. Do you think this could be the problem? If not, what else could it be? Thanks in advance, Mark

 

[Big Rig]

You probably turned the idle balance screws all the way in and that would cause it to not idle. A 2 stroke boat motor is very expensive to replace and if the carbs are not set right you can easily burn up a piston and then the crying starts. please be careful and make sure that your engine is getting enough fuel. these engines are set very lean from the factory to meet emissions and to get milage for the customer and they are high performance engines. They put out a lot of power for the size that they are so if you are not sure about the adjustment, take it to a reputable shop. a good mechanic will get it right and be able to tell if it is right by looking at the color of the plugs. they need to be light brown after a 2-3 minute run

 

[Big Rig]

You probably turned the idle balance screws all the way in and that would cause it to not idle. A 2 stroke boat motor is very expensive to replace and if the carbs are not set right you can easily burn up a piston and then the crying starts. please be careful and make sure that your engine is getting enough fuel. these engines are set very lean from the factory to meet emissions and to get milage for the customer and they are high performance engines. They put out a lot of power for the size that they are so if you are not sure about the adjustment, take it to a reputable shop. a good mechanic will get it right and be able to tell if it is right by looking at the color of the plugs. they need to be light brown after a 2 to 3 minute run

 

[markthbdx]

Thanks for the input, I haven't had much time to look at it again due to work but I will consider bringing it to a shop. I was trying to stay away for the money reason but it looks like it would be a better deal in the long run. Thanks again!