ok heres the deal my brother gave me his 02 big bear 400.i started it up with the choke and made it run.but as soon as u put the choke all the way down it stalles start it back up and same thing.i have to ride it with the choke open alittle.but it will spit and pop on low throttle.i also noticed that on the bottom of the carb there is a small nipple and fuel leaks out of it is there suppose to be a hose there?.if i open her up on a straight no problems.i checked the air filter all good.there was alittle gas in there.but i filled the tank up thinking he had used the atv.well he hasnt used it in the last 6months for sure maybe even more.

 

Pull the carb and clean it REALLY good. May have to replace the bowl if it's leaking. That little nipple is for draining the fuel from the carb to "winterize" or store for extended time. Likely the old fuel has gummed up the idle circuit in the carb.

 

where can i look on how to pull the carb off

 

Look carefully at the ATV and see what has to come off first. Usually on the yamaha's I've dealt with, It's easy to remove the seat and Gas Tank to access the Carbs.... Won't take much anyway. It should be very apparent which things are in the way, and what needs to be removed. Sorry I can't supply a step-by-step, but I can't find a manual online for this one.

 

well pulled the carb cleaned everthing i pulled every screw,nut that was on it and still ran the same.out of ideas

 

Sumpm's been missed. How'd you clean it? I recommend a dip carb cleaner, and lots of very compressed air. It is possible there's something cloging the idle circuit. It might not be something that can be dissolved.

The leaking Bowl quit leaking? I have a leaky bowl on mine too. I've replaced the bowl and still have the leak,... bowl came from an ebay seller.... had rust on the drain screw.

Typically the damage to the bowl will also indicate the shape of the rest of the carb. If there's any white corrosion or rust in the bottom of the bowl it could be there's a problem inside one or more of the passages in the carb. It's also possible you have a vaccum leak around the carb/intake boots. OR,... maybe a problem with the petcock.

Lastly.... nah,.... You're running a 4 stroke.... LOL I was gonna say maybe a weak reed.... I saw a guy make a poor man's reed on You tube the other day,.... outta an old credit card..... but since you have a 4 cycle, I won't suggest that.