It sounds like the needel and seat is getting stuck a little, So that being said then three things come to mind for a fix, #1 the carb needs a tear down and cleaned, Or #2 try shooting carb cleaner down every hole you can with the engine reved to around 2000rpms use the hole can, And #3 Try this first where the fuel line starts to come in to the carb the needel and seat should be with in that area, And also on top of the out side of the carb It "may" have a flat spot in that area [if it is the carb I am thinking it is] Try tapping on the top of the flat spot of the carb lightly with something solid befor and then while trying to start the engine and have some one slowly pumping the throttle to see if you can get it started on it's own, But at the same time you should be carfully look down the carb every once in a while to make sure you are not flooding it with fuel, look for it to be squriting while they are pumping it at times, [BUT DO THE LOOKING DOWN THE CARB ONLY WHEN THE ENGINE IS "NOT CRANKING" OVER FOR YOUR SAFTY DUE TO A BACK FIRE FLAME FLARE UP COULD HAPPEN, JUST BE SAFE ABOUT THIS ALSO WHER SAFTY GLASSES SO YOU DON'T GET GAS IN YOUR EYES.] I would say you should try to get to know the inside of your carb by looking at a parts photo of it some where like a sevice manual that you could find on this fourm Or try looking up your engine at mercruiser.com/part and look at a brake down of the carb to get an idea of what the carb would look like on the inside and find the needel and seat to start your tapping to see if you could free it up from being stuck because over time this get's to be normal for carbs. Good luck I hope this works for you. [BE SAFE ABOUT IT] TRUST ME
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And the webers have different issues, but the same empty fuel bowls......
