carburetor problem

I've got a carburetor flooding problem on my motorcycle that I'm having trouble figuring out. If I try to run the bike with the tank petcock on the carbs flood almost instantly consequently killing the bike. If I leave the petcock off the bike runs like a champ. I took the fuel bowls off and made sure the floats were not stuck. I also removed the float valves and the rubber on their ends looked fine. The bike did sit for around a year so could varnish on the float valve seats prevent the valves from sealing properly? Is there anything else I should look at? Thanks!!!

Something is holding the needle and seat open. Dirt, varnish or something. take the carbs off and soak in a good carb cleaner. Do not soak the plastic floats.

Maybe the float has a crack/small hole and fuel has gone in and prevents the needle valve from closing fully. It happened to my car carb once.

Thanks for the advice. I cleaned the float valve seats and it no longer floods. Now it will only run under load with the choke on. I guess the jets are clogged too. Can anyone recommend a good cleaner I can run through the gas tank? I'd rather try that first before I have to rip the carbs off again.

its always the idle circuit. Check the jets of course, to make sure they are clear, but its usually the transition ports, which are the tiny holes under the butterfly. You have to remove the mixture screws and idle jets, and flush it both directions. MUST have a solid stream coming out of all the transition ports or it'll still run like poo

Cool, I'll do that this weekend if it doesn't clear up on its own today after riding with some fresh gas and cleaner in the tank. This project was fun but now it's getting downright frustrating...last night the battery leaked acid all over the exhaust/frame and corroded it badly :banghead:.

Welcome to the world of the mechanic. Now add a customer that wanted it fixed yesterday for less.

Welcome to the world of the mechanic. Now add a customer that wanted it fixed yesterday for less.

:lol:

I once had a customer try to get his carb clean warranteed. He was putting up a good show of be offended by our pour service too

I tried to explain as best I could that if he lets it sit, it'll need a carb clean no matter who did the carb clean last....UNLESS you prepare the bike for storage properly. He didn't believe me :shakehead