I have two engines, one johnson sea horse, and one montgomery ward sea king. They are both 25hp, and when the covers are off they are identical motors (except for the fuel delivery system). I believe they are both from the 1950's. My problem is with the MW. When idleing, it runs like a champ and when at high speed, the motor misses and bucks really hard. It does this every few seconds while at high speed. Is the problem with a possible fuel/air leak, or ignition?
