2+2 idle conversion

[Jay B]

Hi Everybody. I'm new to the board. I just bought a used 2003 Merc Tracker 125 horse for my runabout. I love the motor, but I'm not wild about the 2+2 feature since I never do any fishing or trolling with this boat. My dealer said the bottom 2 carbs have the low speed circuit blocked off so they don't fire till about 1800 rpm's. Sure enough the bottom 2 carbs have brass plugs installed in place of the idle adjusting screws. Is there any way to convert those carbs over to fire all the time? TIA<br /><br />Jay B

 

[Mercury140-I6]

Re: 2+2 idle conversion

I have heard of guys buying the set of top carbs and putting them in place of the bottom carbs so that all 4 have idle circuits, but have never seen one run like that.<br /><br />Craig

 

[Jay B]

Re: 2+2 idle conversion

Thanks Craig. I'm afraid that's more expense than I want. The 2+2 isn't that big a deal, just annoying to me. Maybe I'll pull one of each carb this winter and see exactly what the difference is. You know, it begs the question- If they just shut the low speed fuel off to those 2 carbs, how do the bottom 2 cylenders oil? I can't see any auxilary oilers to them or anything.<br /><br />Jay

 

[Mercury140-I6]

Re: 2+2 idle conversion

From what I heard from a Merc Mechanic, the bottom 2 do get fuel/oil while idleing, but not enough to make any power or ignite, but enough to lube.<br /><br />Craig

 

[WillyBWright]

Re: 2+2 idle conversion

Two things will happen if you "activate" the idle circuits on the bottom carbs. The idle will be way too fast, and way too rough. Rough idle is the main reason they did that. The 75/90s are the worst idling 2-strokes ever built. The 100/115/125 prototypes were worse.