Carb leaking....

[TampaNate77]

What else could cause carb to leak besides the needle valve and the float being out of adjustment?

 

[Rubixone]

Re: Carb leaking....

I see the low speed or idle needle out way to far all the time, causing the carb to **** gas out the front turn it clockwise all the way in and then back it out a full turn and a half. assuming its a single carb motor, it would be way more helpfull if you gave the year, model, hp, etc.

 

[TampaNate77]

Re: Carb leaking....

73 johnson 65.... this model doesnt have carb adjustments..... I took it out yesterday in the water after rebuild and it starts up and runs but not enough power to come off plane and im at WOT. And when i let go of the gas coming off plane it dies out instantly, and I have have to choke it start it then pull the choke back in and it will start right up. But never comes out of plane with throttle wide open.

 

[Chris1956]

Re: Carb leaking....

Did you rebuild the carb? If so, I would think it is float adjustment or inlet needle and seat are bad. if you did not rebuild the carb, then it is time.

 

[Grub54891]

Re: Carb leaking....

The reed valves could be bad also,they have got to seat correctly to run properly.

 

[TampaNate77]

Re: Carb leaking....

I rebuilt the carbs and set the float exactly how it said to set them from the instructions and i blew into the inlet hoses while the float is closed and i cant blow into it. so i know the needle valve is seated correctly im just lost.... i have no clue. how do i know if the reed valves are bad?

 

[TampaNate77]

Re: Carb leaking....

Also the fuel only comes out after i turn off the motor.... while the motor is running the carb's are bone dry, but as soon as i turn off the motor gas starts pooring out.

 

[Chris1956]

Re: Carb leaking....

Do only a few drops leak after the motor is off, or does a few oz leak? If a few drops, maybe it is expansion of fuel caused by heat of the motor. If more than that, maybe float/needle are a bit out of adjustment or a bit worn. Any chance the float is twisted or leaks internally?

 

[TampaNate77]

Re: Carb leaking....

Do only a few drops leak after the motor is off, or does a few oz leak? If a few drops, maybe it is expansion of fuel caused by heat of the motor. If more than that, maybe float/needle are a bit out of adjustment or a bit worn. Any chance the float is twisted or leaks internally?

There is quite a bit of fuel that leaks out.... and all 3 carb's leak at the same time. I know its not leaking internally because when the carb's were off and i flip the each carb upside down and blow into the fuel inlet's i cant blow anything at all. So i know the float's and needle valves are closing good. And i adjusted them correctly. I have taken these carb's off and on 5 times and used a measure tape to make sure the floats are drooping down 3/4 of a inch EXACT. And the floats are exactly how the manual says they should be when the carb's are upside down. I have had several people tell me "Reed Valves". But how do I check to see if the reed valves are bad?

 

[Chris1956]

Re: Carb leaking....

Nate, It has nothing to do with your reed valves. Is the float made of cork? Sometimes they get loose in the brass clamps. If they are hard plastic, are they cracked or leaking?

 

[TampaNate77]

Re: Carb leaking....

Nate, It has nothing to do with your reed valves. Is the float made of cork? Sometimes they get loose in the brass clamps. If they are hard plastic, are they cracked or leaking?

the floats are all good... i checked them. put them in a bucket of fuel and they all float perfect.

 

[TampaNate77]

Re: Carb leaking....

Nate, It has nothing to do with your reed valves. Is the float made of cork? Sometimes they get loose in the brass clamps. If they are hard plastic, are they cracked or leaking?

how do you check the reeds to see of they are bad?

 

[Chris1956]

Re: Carb leaking....

Reed valves will not cause the carb to leak. If you must inspect them, they are under the intake manifold. Do you know what to look for?

 

[Blacksting]

Re: Carb leaking....

i heard somewhere , if you take a flashlight and shine it on the reeds , if theres' light through the opposite side , theyre bad .

 

[Johny25]

Re: Carb leaking....

Theory sounds good except you forgot to mention the baby mouse that is need to crawl into the crank case and radio back if he sees any light . Ok in all seriousness the reeds have nothing to do with the carb leaking. Chris has you on the right track with the carb needle or float adjustment. Or you are getting crud in the orifice that the float needle sits in. I had an issue some time ago with my carb leaking up through the center of the venturi. Took the carb on and off a half dozen times to clean and adjust only to find out my fuel line was rotting from the inside and the tiny black pieces kept plugging my orifice to the needle seat :facepalm:

 

[TampaNate77]

Re: Carb leaking....

So I took the reed valves off and the top reed valve.... one of the reeds I can see daylight through. The one reed doesnt seem to close completely.

 

[TampaNate77]

Re: Carb leaking....

I can see daylight in #1 cylinder reed valve... and #2 cylinder reed valve. Would this also cause my motor to not have full power at WOT?

 

[Johny25]

Re: Carb leaking....

If your reeds are bad then you will get blowback through the carb. This is not the carb leaking though

 

[TampaNate77]

Re: Carb leaking....

If your reeds are bad then you will get blowback through the carb. This is not the carb leaking though

Well there is fuel coming out of the mouth of the carb and its enough that comes out to where it pours out and drips down to the next carb. And it only happens after the motor has ran for a few minutes and I turn it off.

 

[Johny25]

Re: Carb leaking....

yeah I know that blow back will cause fuel to come out of the carb throat. This is also known as spit back. It can cause loss of WOT, spitting at idle and stalling on acceleration. Do not try and bend the leafs back into shape, just order a brand new set. Your post did not describe any running issues, just a fuel leak so we assumed carburetor.

Get new gaskets for your reed plate, intake manifold and carb while your at it.