i have a 1982 Mercury blueband thunderbolt 50 hp 4cyl with firing issues I can’t seem to figure out. We have rebuilt carbs completely and fuel pumps. Finally tracked the problem down to firing issues. It’s has a new cdi box and a new trigger put on it. Motor will crank and run and idle smooth and fire on all cylinders fine. But when you rev the motor via the neutral button on the throttle it quits firing on all cylinders except number 1 and it occasionally hits on the number 3 cylinder. No fire at all on 2 and 4 until it’s put back down to idle. Help would be much appreciated been trying to tackle this for a while.
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