1997 115 hp Mariner idle setting question

[109jb]

I have a 1997 115 hp Mariner inline 4-cylinder outboard and need to adjust the idle mixture. I pulled the hood off and it appears that the top two carburetors have mixture screws with springs under the screw head as you would expect. The bottom two carburetors don't have springs under their screw heads. I didn't have time to do anything with it at the time, but is this correct, or are they all supposed to have the springs and be adjustable?? If it is supposed to be the way I see it, then is the idle mixture adjustment only handled only by the adjustment screws on the top two carburetors?? Doesn't seem right, but I though I'd ask.

 

[achris]

Re: 1997 115 hp Mariner idle setting question

All you see is correct. These engines are known as "2+2". The bottom 2 carbs lean out below about 1800rpm and don't fire. Just adjust the top 2 and it will run just so.....

Chris.............

 

[109jb]

Re: 1997 115 hp Mariner idle setting question

Thanks for the info. Just didn't seem right to me. I'll adjust the top two and see how it goes. Thanks again

John B.