2001 150hp leaking fuel from carbs... help!!

Working on a friends boat, engine is a carbureted 150hp, saltwater ed. Motor has sat for over a year. Here is the problem: I have cleaned all of the carbs including the needle and seat, and all appear to be closing properly when the float bowls fill. When i start the engine, it will run and idle well for a few moments but then fuel will literally pour out of lower 2 carbs. Note that while the boat is on the trailer, the engine is trimmed up probably 15 degrees or so; I suspect carbs may be working ok, and the angle the engine is running at is causing the fuel to leak from the carbs. My friend who owns the boat claims that angle is reasonable for it to run at and is not the source of the prob. Before we spend any more money on parts, i would really appreciate some input on what the problem and solution may in fact be. Thanks a ton in advance!

If it is not pouring out of fuel bowl gasket area then the needle is not closing!!(Cause) float not adjusted rite,hitting carb body before needle can close.Readjust floats!!

all three float levels are adjusted properly...

is there a plastic gasket under seat?It has to be an o ring, gasket,thats all that is there that i can think of.Are you sure they gave you the rite kits?Because i had this happen with one carb on my johnson 185,the first two kits i put in first two carbs,were rite but the third one did exactly what you said.The gas would just poor out I finally found that the needle and seat was the wrong one,

I am not sure abt that... The little o-ring for the seat does look pretty bad. I will get some new needle and seat assemblies with gaskts/o rings and let you know what happens. any tips on where to get stuff like that for cheap?? thanks for the quick responses!

There are lots of places!!Johnson.com/iboat.com/mastermarine.com/outboardexpert.com/wholesalemarine.com/boatpartstore.com!!These are sites i go to.

Please read. 2001 50 hp 4 stroke leaking fuel from carbs through plunger rod. Rubber bellow deteriorated. After 5 posting on various Mercury forums, and getting no reply, I have discovered that if you have to ask what a plunger rod is and the rubber bellows that go on it, you know nothing of Mercury, Tohatsu or Nissan carbs. These motors all take the same carb kit and these same carbs are used on many 9.9, 20, 30 hp motors. One local "certified" Mercury mechanic .had to look on computer to see what a plunger rod is. Another said he would rebuild carbs for 350 dollars but I must get an intake manifold gasket. This 50 4 stroke does not have a gasket only O rings . If anyone , novice or professional ever rebuilt this carb, you would not forget what a plunger rod is, the rubber bellows that go on it, and the function they serve.
Upon disassembly, for the "professional" mechanics and novices, the plunger rod, about 1 1/2 long by 3/32 D, is activated by throttle advance, goes through a brass fitting about 1/2d with 7/64 hole in center {very loose plunger rod fit and not sealed**. Rod goes to bottom of bowl to depress about 1/2 inch plunger that forces more fuel into carb. To my best assumption, the rubber bellows on rod at outside top of carb, serves to protect from debris and to protect from fuel linkage.
As someone who does not have great knowledge, it was inconceivable that no one answered this after all those postings. Maybe this will help someone else who may need an answer. Thanks for your forum.

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