Carburetors dripping fuel

[imstillatwork]

The Evinrude that I recently aquired is up and running pretty well. It has an occasional miss, which is you can hear, and see the motor twitch slightly.<br /><br />I rebuild the carbs and its a bit better, smoother running for sure, but the fuel still drips out the carbs. not muh, but after say 2 or more minutes of running, there is a fuel puddling up on the intake of the carbs. all three of them do this.<br /><br />right now I'm running with the air intake box off. ON the air intake box at the bottom there is a vacuum line attached. Is that to recycle fuel that drips out? I haven't had the boat in water yet (I ran the motor with the lower unit in 3 layers or large plastic bags though) <br /><br />Is it normal to accumulate fuel on the throttle plate since it is less than half way open, and that would cause the dripping? the floats are doing their job, I'm sure of it. The primer bulb tightens up nicely, and NO fuel leaks while pumping the primer bulb.<br /><br />Another question: should there be some sort of air filter element in the air box or in the engine cover? ? <br /><br />its a 1981 evinrude 70hp. sorry for making you read a book up there!<br /><br />THANKS!!!<br /><br />Heres the beast: http://www.lot-o-nothin.com/lotonothin/boat.cfm . . don't laugh to hard it was free ok?

 

[Silvertip]

Re: Carburetors dripping fuel

Not much dust on the lake so no air filter is used or needed. As for the carbs, are you sure the float level is set correctly. If its set too high, it won't shut off fuel flow and the carbs will run over. During the rebuild, did you replace the needle and seat. If not, a leaky needle and or seat may be at fault. Did you get the needle inserted properly (some folks confuse this step and put them in upside down). The vacuum line at the bottom of the air box is indeed to draw off excess fuel.

 

[imstillatwork]

Re: Carburetors dripping fuel

The needle and seat are new, and are installed correctly and work. The float may need to adjusted. I set them all at exactly parallel to the carb body. I'll adjust them down a bit.<br /><br />I am also getting a grey sludge out of the exhaust - but the gear oil is clean when I check it at the drain. odd??

 

[Silvertip]

Re: Carburetors dripping fuel

Have you double-checked fuel line fittings at each carb. These may not be tight making it appear its an internal leak when its just fuel running down the side of the carbs.

 

[imstillatwork]

Re: Carburetors dripping fuel

fuel lines are tight, after the rebuild I used small stainless clamps.

 

[imstillatwork]

Re: Carburetors dripping fuel

however, I am boat dumb (now totaly engine dumb though) and have never had an engin with mechanical advance. so i have yet to doa link/sync - which I know it needs badly before I try figuring out these trivial little problems.

 

[papasage]

Re: Carburetors dripping fuel

if pumping the bulb dosent make it leak it probabley just excess fuel . that is what that tube is far . it probabley want do it at high speed .