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Why is gas leaking out my carb?

Its a 1961 Evinrude Lark III 40hp. Model #35524

Just finished a rebuild of the carburetor, using Johnson/Evinrude carb kit 439074. Carb was torn all the way down to a bare shell, soaked on carb cleaner overnight, and then cleaned with spray cleaner and compressed air. The welch plugs were removed for this.

Got it back together, making sure the float height was per the manual - meaning that with the carb upside down and horizontal, the float is sitting level. That's how my manual says to do it anyway.

But, when I get it back on the motor and squeeze the primer bulb, it leaks from this hole, circled in red:

EvinrudeCarbLeakingHole.jpg


I took the carb back off and tweaked the carb float, even though it was pretty much fine, and it had no effect on the problem. The primer bulb does get hard, so maybe this is some kind of overflow?

I also played around with the low speed needle, since its adjustable and it also had no effect on the problem. (Thats why the knob is off in the picture)

I am not very familiar with this carburetor, so any information is appreciated. Based on the experience I do have, it shouldn't do this, but this outboard is older than the ones I usually work on and I don't need to use a primer bulb on my '56 Chev. ;)

For reference, I also replaced the engine's entire fuel system - all new fuel lines (all the way to the tank!), and a new filter, and I disassembled, cleaned and inspected the fuel pump.
 
You've probably got the float set properly but redo it as follows.

(Carburetor Float Setting)
(J. Reeves)
With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

Now, the only fault that will cause fuel to flow out of that hole you pictured is that the float chamber vent to the outside atmosphere is clogged with something.

I've seen carburetors that would have that vent passageway clogged with ant trails, mud wasp nests just to mention a few. Study the carburetor, find and clean out that float chamber vent passageway.
 
Ok, I'll take it out and take a look. If I can get any pics to come out, I'll post them, but for close ups my phone is terrible.

EDIT: Well, I feel like an idiot. Not because I hooked up a battery and flipped on the stern light to take the carb off the motor in the dark, but because of what I found. I took the float and float valve out, and I just happened to check down into the float seat - yep, had a piece of old gasket in it. How that piece of gasket got in there in the few seconds between installing the seat and the valve I may never know, but I do know I feel like a fool for not checking myself. I bet that was the problem.

I will hook it back up tomorrow and post the results, even if it makes me look stupid! ;)
 
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I have a 1966/7 Evinrude Sportwin 9.5, and having a similar problem: siphon bulb won't firm up, and gas is shooting out a hold in the carb -- could this be a float problem??
 
I had a very similar problem, I had to clean out the carburetor and I found dirt lodged in such a way that it kept the float valve up which caused a constant gush of gas out of the carburetor. I think a good investment would be a carb kit (pays for itself in fuel savings.

I hope this helps.

Robby
 
This post is two (2) years old. Let it go. If you're having a problem, start a new thread/post.

What's the logic in starting a new thread or post explaining the same problem? In my opinion, it's better to build on the same forum post instead of having multiple threads explaining the same problem. Older Forum threads like this will often stay indexed in Google for YEARS resulting in a lot of referral traffic to the forum. So you're better off adding more content to this thread because people are going to click over to this thread directly from Google. Thankfully, I found this thread, through Google I might add, because I have the same issue with my outboard.
 
What's the logic in starting a new thread or post explaining the same problem? In my opinion, it's better to build on the same forum post instead of having multiple threads explaining the same problem.

And now, it's going on 4 years old. Always got to be just one to go against the flow.
 
It is a real PITA for us to read all the way through a thread with the good intention of helping somebody, only to realize we are dealing with somebody that has left the forum years ago and no longer needs our attention..........That's why. Wasting our time and brain. If you want help, ask for it with a new topic.
 
It is a real PITA for us to read all the way through a thread with the good intention of helping somebody, only to realize we are dealing with somebody that has left the forum years ago and no longer needs our attention..........That's why. Wasting our time and brain. If you want help, ask for it with a new topic.

Shame you guys cut this one short, it was just getting interesting. I have exactly the same problem as this guy and it makes no difference when his problem arose or who/when somebody comes with a solution. The solution is all i'm interested in.
 
If the solution existed within this old post, there would be no need to enter anything further.

HELP TIP: IF YOU HAVE A QUESTION THAT HAS NOT BEEN ANSWERED TO YOUR SATISFACTION IN THE ARCHIVES, IT IS ALWAYS BEST TO START A NEW THREAD OF YOUR OWN. BY STARTING YOUR OWN THREAD, YOU WILL RECEIVE THE MAXIMUM NUMBER OF VIEWS BY FORUM MEMBERS.

Below are some additional forum policies in hopes of all members will follow, Thank you.

1. Please do not reply to old topics or hijack existing topics. Old topics of a technical nature are like a library book, Please do not write in them.
 
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