Another Leaky Carb......

Don't mean to sound like a knob, but I read the recent thread "Fuel dripping from overflow tube" and did a search but could not find the answer to my specific question:

Which vent hose on the carb leaks when your float is stuck open? Is it the one on the lower left side of the float bowl that has the drain screw (3mm allen head) directly above it?

Bike has not been ridden in a week, started leaking yesterday while sitting quietly in the garage. Noticed the gas coming from the hose with the drain screw, so I immediately checked the screw but it was tight. After reading the other thread, suspect I might need a new valve seat/O-ring assembly. Just wanted to post for advice before I dive in. Thanks in advance to all who respond :devil:

Is it the one on the lower left side of the float bowl that has the drain screw (3mm allen head) directly above it?

no, that screw is a stopper. if you loosen it, it will drain the carb. sometimes a bit of dirt can get trapped under that screw, and not seal all the way.

i am NOT sure if there is an o-ring or gasket that the screw seats into. might want to check the parts diagrams for that.

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no, that screw is a stopper. if you loosen it, it will drain the carb. sometimes a bit of dirt can get trapped under that screw, and not seal all the way.

i am NOT sure if there is an o-ring or gasket that the screw seats into. might want to check the parts diagrams for that.

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Sorry ARin. That is the overflow hose. The 3mm allen screw is used to drain the float bowl, but if the fuel level in the bowl gets too high, like when the float is stuck or improperly adjusted, fuel will drip from that hose, even when the screw is tight.
Sorry ARin. That is the overflow hose. The 3mm allen screw is used to drain the float bowl, but if the fuel level in the bowl gets too high, like when the float is stuck or improperly adjusted, fuel will drip from that hose, even when the screw is tight.

ya, you're right.

sorry.

Time for a new needle and seat kit my stealership just charged me $45 for the kit needle seat and screen.

Don't mean to sound like a knob, but I read the recent thread "Fuel dripping from overflow tube" and did a search but could not find the answer to my specific question:

Which vent hose on the carb leaks when your float is stuck open? Is it the one on the lower left side of the float bowl that has the drain screw (3mm allen head) directly above it?

Yes, overflow and drain hose is the same. If it leaks from there, its either a dribbling needle/seat or float level is set too high. Fuel is higher than the "standpipe" in the float bowl. Other 2 hoses going over the top on each side is a bowl vent. Its important that these remain clear to keep the bowl area at atmospheric pressure. If they become plugged, pressure drops and fuel will dump into the engine from the carb. I snipped the "over the top" ones right under the bowl (wont ever become plugged with dirt) and split the very bottom ones lengthwise an inch which wil still give you a good fuel drain, but splitting the ends keeps them from plugging too easily with dirt.

Before you spring for a needle, etc., pull the carb and just give it a good cleaning, especially around the float. Mine was doing the same thing and it turned out to be a sticky float. After a good douching, it was all good...SC

Yeah, I just went thru this. One thing is you should drain your float bowl after you ride. I left fuel in my bowl and thats when i started having problems. I have and 05 and I had to replace my needle vavle. The other parts are not replaceable on the 05.

Your float height should not need adjusting, but definately give it a good cleaning. The needle valve was only $30.00.

charlie

I had the same thing happen this spring to my '06 WR450F after it sat for a couple of months. Usually you just have to ride it a bit and that will free up the float. I had to take the bowl off and make sure everything was clean and just put it all back together and that stopped the leak. Must be something in the gas as I haven;t had this happen for a few years.

Before you spring for a needle, etc., pull the carb and just give it a good cleaning, especially around the float. Mine was doing the same thing and it turned out to be a sticky float. After a good douching, it was all good...SC

I agree.... A good cleaning gets the bike back to 100%

Raise the float height by 1mm over what the manual says. {9mm i think}.

this will LOWER the fuel height in the float bowl. the bike will still run the same but you will not loose fuel when the bike is on the side stand or when you going around a corner.

this is a MUST for all FCR carbs!!!!!!!

mine was dribbling all over the trail and my shop till i did this. also clean the needle and seat out while your in there. 99% sure you WILL not need to buy anything.

good luck.

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