Have a 1978 Mercury model 700 70hp 3 cyl. twin carbs.
Motor would have low power when I put the throttle down in forward. I replaced a float and needle and got it running a little better...it would go good if I eased up the throttle. If I punched it down it would sputter with low power. While adjusting the idle screws I discovered that with the front cowling cover off it would take off and run great...getting lots of air. Put the cover back on and back to sputtering. Anyone have any ideas? Am I borderline too rich for the available air with cover on? So far it’s been running best at 1 to 1-1/4 turns out.
Motor would have low power when I put the throttle down in forward. I replaced a float and needle and got it running a little better...it would go good if I eased up the throttle. If I punched it down it would sputter with low power. While adjusting the idle screws I discovered that with the front cowling cover off it would take off and run great...getting lots of air. Put the cover back on and back to sputtering. Anyone have any ideas? Am I borderline too rich for the available air with cover on? So far it’s been running best at 1 to 1-1/4 turns out.