I have a 1991 90 h.p. mariner outboard which seems to run ok except occasional rough idling .Im not sure if i have a problem with it but for some reason when i fogg the carbs and also when i was spraying engine tuner into the carbs the top carb does not seem to even slightly bog the engine no matter how much i fog that particular carb ,i checked that cylinder for spark and i seem to be getting good spark but i did not compression test it, is this normal?
