1993 70hp Force Carburator Adjustment?

[Happy Camper IV]

Hello,
My first post, great forum!
I have a 1993 70HP three cylinder Force outboard on a 17' Bayliner bowrider. It says Mercury Marine on the back. It has only one carburetor attached to a manifold. I have cleaned the carb and it looks like new inside. Basically the engine runs great. The compression is within 2 lbs of 120psi on all three cylinders. However, after "trolling" around for a few minutes, when It is time to give it full throttle, it takes off OK, but it is usually missing on one of the cylinders for the first 30 seconds or so. It slowly clears the cylinder and takes right off. I have new gas and new plugs, but it still misses. I see on the carb, there is an adjustment screw. What does this screw adjust? and How do you adjust it. I am hoping this is some sort of a low speed mixture screw. The engine acts like it is running too rich at low RPM's. Any ideas?
Thanks,
Scott

 

[further]

Re: 1993 70hp Force Carburator Adjustment?

Don't know your exact motor, but that is probably the fuel/air mixture screw. Should be set 1 full turn out from lightly seated. Careful not to adjust it too lean.

 

[Happy Camper IV]

Re: 1993 70hp Force Carburator Adjustment?

Thanks for the advice. I checked the position of this screw when I cleaned the carburetor, it was set to three full turns out from lightly seated! Not knowing any better, I put it back to that position after the cleaning. I will make the adjustment and see how it runs. If this screw adjusts the idle mixture, (out for richer) that would explain the loading up behavior I have been seeing.
Results to follow.