I believe I have "C" carbs,,question,, is the bottom carb lean & rich adjustment for high speed only ,,I believe I heard the top was for low speed and idle and the bottom carb was for high speed.Thanks,,,Mike
Each carb feeds 2 cylinders. Each carb has a fixed main jet, not adjustable except by changing the size of the jet.
Each carb has an idle mixture screw. You adjust the screw on one carb independently from the other.
Adjust each screw with the motor warmed up, idling in gear. Find the range of adjustment which gives best idle speed and then turn the idle screw approx 1/8 turn CCW (rich). After adjusting both carbs this way, do an acceleration test.
If the motor will not accelerate properly from an idle (i.e. it bogs), richen up each needle another 1/8 turn or so and try it again.
Jot down your motor's serial # and find the appropriate parts diagrams at this site:
