1982 75Hp runs but is missing now

[jrat317]

Ok, I have completely rebuilt the carbs (w/ new orifces(jets) ) and a new carb kit. It starts in the cold while the motor is cold and I am very happy with this; however, it has a miss now. The miss is so bad sometimes that it will cut the motor off occ***ionally. When I am running at 4200 rpm, the motor runs great, but will have a really small miss occ***ionally, every few minutes or so. At wide open, the motor runs flawlessly. I got home and replaced the spark plugs to see if that would fix the problem. The miss is still there. Where should I look next? Is this indicative of a larger problem?

[boats.net]

Would have to test it when it has the miss, try a timming light to see if cylinders are misfiring.