I need serious carb help on 2001 XT225 California model

I want to do a serious payback for a good friend that deserves it but I am completely stumped. He has a 2001 XT225 Serow that the carb has been touched by too many people.  I am quite a capable bike mechanic, so I downloaded a service manual, disassembed cleaned the entire carb and set everything at factory settings.The bike starts right up no problem but after a minute or so it starts to leak gas out the overflow on the bottom of the carb.  The float is set correctly and the needle and seat are fine.  I replaced the petcock only  too have the same problem. The only thing I find odd is that if you look at the right side of the carb, while sitting on the bike, there is  a brass"L" shaped line out of the carb pointing downward that goes nowhere.  The carb numbers say this is a California model carb but there is no canister for it to go to.  Can this make the difference in the fuel leaking?


Did you try plugging it up? Does it run and leak after that?

Does it leak while just sitting, before starting?  If it only leaks after running for a little while, does it stop after the engine is turned off? 


Did you try setting the float "wrong"?  Adjust the float to see if it stops.


You might try asking over at XT225.com  there are a few fellows over there that might be able to help.   Here's a thread with some ideas: http://www.xt225.com/forums/ubbthreads.php?ubb=showflat&Number=116416#Post116416

You might try polishing that new float valve seat with Brasso or the like and Q tips . Sometimes they are not exactly what they should be and need slight attention .

Pull off the bowl and hook up the gas.  Turn the gas on while holding the floats up/closed with your finger.  See where the gas is coming from.

 Are you sure it's the overflow leaking, not the drain?

 Did you set the fuel level as described in the manual?

I tried the xt225 forums but their website is messed up and wont let me access it.  The float is set to 14.5mm which is dead between the 14.1-15.1mm  specification.  fuel is definetly coming from the float bowl overflow. On this carb the overflow and bowl drain both drain out of the  small nipple on the bottom of the carb but are actually separate circuits.  I installed a new float bowl drain screw thinking that was the problem but wasnt.  My next move is a new needle since it has the neoprene tip and its a brass seat.

You might try polishing that new float valve seat with Brasso or the like and Q tips . Sometimes they are not exactly what they should be and need slight attention .

 Try that^ first .


Something else to look for is a crack in the float bowl overflow brass tube . You may not be able to 'see' a defect , so , attach a hose to the top of the tube ; fill the bowl with liquid ( drain screw shut ) and blow through the hose . If the tube has defects , you should be able to see bubbles .

The tube on the right rear side is on the non-CA versions as well. My riding associate has his in my garage, and I just went out and looked at it. It is a vent to the float bowl and should have a hose from it to the area behind the engine and in front of the swingarm where the other hoses go. Don't plug it.  The gas come into the carb, and the displaced air goes out of this tube.The factory (NOT some third party parts house) parts diagram shows most of this stuff. The hose needs to be there: the length of the hose acts somewhat as a filter in that is is long enough that dirt can't easily get all the way up into the carb. Without the hose, dirt can easily get there. 


Overflow is probably debris in fuel, or a stepped Viton tip on the float needle and/or a bad seat. Or both. I'd install in inline filter, and consider replacing the needle and seat if the there is any sign of a step in the rubber (Viton) If it has the usual exposure to crappy ethanol gas, a careful cleaning and rebuild with new rubber parts and gaskets will no doubt resolve the problems.

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