Mercury carb adjustment

[tekebird]

I have a 2002 mercury 9.9 2 stroke. I rebuilt the carb and it seems to be running rich. How many turns out is the correct amount on the adjustment screw?

 

[sschefer]

Re: Mercury carb adjustment

I have a 2002 mercury 9.9 2 stroke. I rebuilt the carb and it seems to be running rich. How many turns out is the correct amount on the adjustment screw?

The rule of thumb is 1-1/4 to 1-3/4 the manual will tell you or maybe somebody has that manual and can chime in with the manual setting.

I start with 1-3/4. With a 9.9 you can put it in a barrell and start it up. When it warms up, put it in gear at idle. I put a screwdriver on the idle screw and then put mark on the handle with a sharpie. I start turning in the screw and count the turns by watching the mark. When the engine begins to run rough, I back it out half the amount of turns that I turned it in. Since I start at 1-3/4, on smaller motors I repeat the process once more and it's usually dead on. On a bigger motor I add a 1/4 turn to the half way point and that usually gets it without bog.

 

[Fallen001]

Re: Mercury carb adjustment

sschefer,

I have a 1976 Merc 110 9.8

Question:

I've read that you should close the screw all the way then open it about 1 - 1/2 turns then start the motor (after it's been warmed up) and then work on the idle from there ...

Or

you can start the motor, warm it up, and then work on the idle as you described ...


my question is grounded in the following information:

I have a tough time starting without a bunch of throttle and pumping gas into it before the first attempts to start ... If I cut the throttle too quickly, it will sputter to a stop ... usually from the mid throttle area to the start section on the tiller handle ... I cannot drop the throttle into the "shift" area on the tiller handle to have the motor "idle on forward"

I played with the screw a bit last night and now I can decelerate into the "start" area on the tiller but I have to do so slowly ...


Based on that information, do I start by "resetting" the screw to the base and open it a turn and start thew process OR should I start the motor, as it runs now, and work on it from there ?


Thanks