I've had this boat for 10 years and it's always had a slight misfire when you pull it out of gear. I'm not sure if maybe one carb is set a little lean. I pulled the plugs and the top left cylinder had the cleanest looking plug. Anyways, this outboard had four carburetors on it. It's a 1991 model and I can usually fix this problem by spraying carb cleaner into the hi and low speed jets of each carb. I did this and took it out a week later and it didn't misfire once the entire two hours I was out. Then I took it out a few weeks later and it was doing the same thing. It would misfire anytime it was under 1400rpm, but this time it was to the point where it was running so lean it would barely staying running to idle down enough to make it to the dock. Did the carb just happen to suck up another piece of dirt in the jet or something? I don't get it. The last 3 times I've flushed out those jets in the past 5 or 6 years it's always run great for at least the rest of the season.