I took my carbs off to clean the needles because they were sticking and my top carb had a venturi in it but some reason the bottom one doesn't I was just wondering if I some how lost it because my boat is still not running right so if someone could tell me if both carbs are suppose to have a venturi are just the top one or was it the bottom one, did I get the 2 mixed up....my motor is a 1986 mercury classic 50 seriall # ob257964.......thanks