Carr400EX
10-03-2002, 12:38 PM
I have a 2000 400EX with a WB E-series muffler and a drilled air box lid. I increased the main jet size to 155 to get good performance. It has been running well for nearly a year now with these mods. Recently, however, fuel is coming out of the carb overflow tube. There is enough fuel to soak the rear swing-arm skid plate in a 20-minute ride. I have cleaned the carb and checked the settings. I replace the float valve, which had an easily discernable wear ring on the rubber tip. I checked the float for leaks but found none; I bought a replacement anyway. After all of this, it still overflowed fuel. I removed the float bowl and actuated the float with the fuel line connected to see if it would shut off fuel flow. It did. The float used on 400EX’s is not adjustable so I can’t fix the problem that way.
Has anyone had this problem? As you can imagine, I don’t really want to become a flaming (literally) rider. My local Honda shop isn’t sure what to do either. They did, however, suggest that the float seat might be scratched. This would explain why I can shut the fuel flow off by manually activating the float (with more pressure) and why it leaks during use (not enough pressure on the float valve to make a seal). The dealer said the only way to get a replacement valve seat is to buy a new carb body since the seat is pressed into the housing. Ouch! There’s some money I really did not want to spend.
I would appreciate any advise you can offer.
Has anyone had this problem? As you can imagine, I don’t really want to become a flaming (literally) rider. My local Honda shop isn’t sure what to do either. They did, however, suggest that the float seat might be scratched. This would explain why I can shut the fuel flow off by manually activating the float (with more pressure) and why it leaks during use (not enough pressure on the float valve to make a seal). The dealer said the only way to get a replacement valve seat is to buy a new carb body since the seat is pressed into the housing. Ouch! There’s some money I really did not want to spend.
I would appreciate any advise you can offer.