Carb leaking lots of fuel

Hey guys, got a 2000 CR 125. Rebuilt the carb, put all new needles/jets/screws in. Also, all new gaskets. For some reason my carb is puking a ton of fuel out the overflow (even when running). The float valve is new, as is the needle as well. Did i miss something putting it back together? Maybe the tab on the floats needs to be bent up to seet the needle valve all the way shut?? Any other suggestions?

my bike does this too. I dont know if this is natural or if something needs to be fixed. its only when it gets leaned over, but it doesnt have to lean much to leak

It shouldn't overflow at all, if it does ur level is probably set too high. Take out the carb and take off the bowl and connect the gas line back up. Then turn on the gas and lift the float, it should stop the flow. That will verify the valve is good. Then set ur level to 15mm from the bottom of the float to the base of the bowl flange. Make sure the float tang is just touching the valve and not compressing the valve spring when u set the level. Put the bowl back on and test it for overflow before putting it back in the bike.Good Luck

Sounds like some good advice. I'll give that a try next week and let you know how it works. I'll bet that the float is not pushing the valve completely closed inside the bowl.

could you explain that again, but a little simpler?

I'm not a mechanic but I did sleep at a Holiday Inn Express. MXRider it sounds as though ur level is just slightly too high. When u take off the bowl u want to hold the carb, side ways so the float is just contacting the float valve. If u gently push the float up with ur finger u will feel the spring action of the float valve prior to it stopping. That is the spring that u don't want to have compressed while setting the float level. U want to set the float level right when the float tab or tang is just at a point prior to the spring compressing. The float is measured 15mm for a 00 and 01 from the bottom of the float to the bowl flange of the carb. That measurement is 7.5mm for an 02. After u put it all together prior to putting it back in the bike test it to make sure no gas over flows since sometimes the float gets stuck during the process of putting it together, I think from the white baffle in the bowl.

The floats in the carb are stuck. My CR125 does that even after a rebuild. Tear into the carb and put some sort of lubrication on the float bowls where the floats pivot. That's what I did and problem solved. I sprayed them with carb cleaner and them a little WD40. It burned a little WD40 on the piston but doesn't hurt it. Since then it's been great :thumbsup:

I'm not a mechanic but I did sleep at a Holiday Inn Express.

:thumbsup::moon: :moon:

Isn't it normal to leak out overflow when leaned over? When me and 2 other guys stopped to help a kid who fell, we all leaned our bikes against the same bank, all at about 30 degress, and all were leaking out of the overflow.

It shouldn't overflow at all, if it does ur level is probably set too high. Take out the carb and take off the bowl and connect the gas line back up. Then turn on the gas and lift the float, it should stop the flow. That will verify the valve is good. Then set ur level to 15mm from the bottom of the float to the base of the bowl flange. Make sure the float tang is just touching the valve and not compressing the valve spring when u set the level. Put the bowl back on and test it for overflow before putting it back in the bike.Good Luck

:thumbsup:

I would just add, that if when put back together if fuel flows non-stop, then it could be the O'Ring that is on the valve seat. Brass piece that float valve goes into. (Which by your description sounds like what is going on)

"CARRY ON"

Good Luck :moon:

I guess it all relates to how far its tipped over but I was really just trying to address the problem of gas pouring out of the carb but in general I have found it has to be leaned over quite a bit in order for gas to overflow out of the carb.

Also make sure that your carb float doesn't have a hole in it and gets filled with fuel.

Sorry to bring this one up again, but my problem is similar but not identical. I ride an 96 CR250. When running everything is good. But once I kill, there is a small, but steady leaking of fuel. I have to remember to close the petcock. That is an easy fix I realize, but I want it to be right. If everything seems normal when running, and the fuel only leaks when gas is in the "on" position when the engine is off - could it abe that the floats need adjusting?

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