Gas stream coming from carb,why?

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Hello,I have a merc classic 50(45hp Ser.#OB246833)that all of a sudden is giving me grief.Ran it 3 weeks ago,no probs.Took it out sunday for a river cruise and ran fine for about 30 seconds and lost power so I went to a marina and put sea foam in her and purred like a kitten for about a half hour and lost power again.This happened 3 times until day was done.So I get it back home and cleaned the carbs and seemed to run about 3/4 power(on muffs) and a buddy looked at the carbs and a stream of gas was pouring out of the bottom carb out of some type of a screw with a hole in it(above the throat).What is this screw with a hole in it and why would it pour a stream of fuel out of it?trying to take the carbs off is kind of a pain,but I have a feeling I will have to do it again anyways. Thanks tons for your help! Dave
 

Mercr

Seaman Apprentice
Joined
Mar 30, 2006
Messages
40
Re: Gas stream coming from carb,why?

Being a carbosaur, yet not knowing much about marine carbs, it sounds like the float may have gotten stuck open - perhaps by a fleck of varnish the the SeaFoam dislodged?
 

Oatsmandave

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Joined
Mar 29, 2006
Messages
31
Re: Gas stream coming from carb,why?

I was kinda thinking that,but what is the screw about and why isn't pouring out of the throat which is lower on the carb than this screwy screw with a hole in it?haha
 

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Gas stream coming from carb,why?

I had also took them both off and cleaned with carb cleaner when I got it home and started it up today and that is when we noticed this leak but like I said in the last post I thought the float would be open for some odd reason,and why isn't fuel coming out of the throat of carb instead of that screw?I know it sounds od but that screw is above that throat<br />Thank for input Mercr.
 

MercFan

Petty Officer 1st Class
Joined
Dec 31, 2005
Messages
347
Re: Gas stream coming from carb,why?

Isn't that screw simply the overflow for your float?<br /><br />ie., if your float gets stuck, the excess gas will run out there.
 

deejaycee_2000

Captain
Joined
Mar 28, 2006
Messages
3,447
Re: Gas stream coming from carb,why?

that would be the air screw, that carb is very dirty that is why all the fuel is coming out the little hole there, only solution is take off the carb and clean out. Happened to mine a week ago and it's back up and running fine now ...
 

tashasdaddy

Honorary Moderator Emeritus
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Nov 11, 2005
Messages
51,019
Re: Gas stream coming from carb,why?

when you say you cleaned the carb, did you submerge the parts in cleaner for 24 hours, and then blow out with compressed air. did you used new part to put them back together. if you didn't you just took it apart and put it back together.
 

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Gas stream coming from carb,why?

Yes, you are right Tashasdaddy.I am getting a carb kit,gaskets and also new floats for the carbs,Thanks,I will let ya know what happens.
 

MercFan

Petty Officer 1st Class
Joined
Dec 31, 2005
Messages
347
Re: Gas stream coming from carb,why?

Great stuff Oats!<br /><br />Carb kits I'm guessing include Needle + Seats?<br />To me those are the 3 most important parts in a carb. Floats, needles, seats. Though the floats don't regular replacement, it's nice to replace them, so you know what you got, if you bought the motor 2nd hand.
 

gungalunge

Petty Officer 2nd Class
Joined
Mar 5, 2006
Messages
126
Re: Gas stream coming from carb,why?

I did all 3 of my carbs, and be aware inside the carborator dirt can roll around and clogg small holes.Take the carb body all apart lay it out so you know you dont mix nothing up.. compressed air works to blow it dry after you soak it in cleaner ,I found 3 holes where the trhottle plate butterfy is .. take and poke a peice mail tag wire in the holes in and out about 5 times and twirl it around in there, my holes in my dried out carbs took some poking to get then free . also get them floats right . decarboning locks dirt in these holes .and they are the ones they are suppose to clean .
 

tbrracer

Cadet
Joined
May 21, 2006
Messages
25
Re: Gas stream coming from carb,why?

I have classic 50 also and I am having the same problem I have completely dissasembled the carbs and cleaned VERY WEll with air, soaked them etc..<br />Here is what happens on mine... It runs fine until about 3/4 throttle then go a little bit more and fuel starts pouring out of the top carb out of I guess is the overflow for the bowl like you guys are saying its a jet with a number on it to the top right if looking at the carb. Not in the butterfly area. The bottom carb does not do this is the float set to high on the top carb? But if so why does this only happen at 3/4 throttle or above?? And yes the motor is level sitting in a 55gl drum with water for testing!<br /><br />Any help is greatly Appreciated..<br /><br />Rick<br />email: rkrawitz@goschauto.com
 
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