QuestionIt's a 95 honda shadow 600, and has a major flooding problem. I have taken the carb apart countless times, and replaced the jets and float already. But yet still have a problem with it flooding. Would i need to get hotter sparks? Or break down the engine and check for a stuck valve? If it is stuck, how should i unstick it?
AnswerSteven, Can you define "flooding" for me? Is fuel coming out of both of the overflow tubes in the float bowls? If so, and you replaced both of your float valves, then there must be a problem with either the floats themselves or the float bowl chamber is not venting properly.
Have you checked ALL of the air and fuel passages? Verified that the float valves will close by blowing air into the fuel line inlet and then closing the floats? If they are closing, then there could be blocked air passages that feed the metering circuits or you have some vacuum lines on incorrectly.
The carbs each have air-cut valves, so be sure that they are not bleeding air into the engine, causing a rough idle that is often compensated by raising the idle speeds, which takes the idle circuits out of the loop, metering fuel from the main jet circuit and low speeds.
The carbs have enricheners, instead of chokes, so they have to close properly. If the choke cable is worn inside, the strands can cause the enricheners to hang up adding excess fuel into the engine at idle.
Check your carb diaphragms for any pinholes or tears. Any damage to the diaphragms must be repaired, by replacing the parts. If the slide needles are not clipped into the slides properly, they will dance around causing metering issues. Make sure that the emulsion tube holes in the main jet holder are all clear and clean. Blocked holes will cause excess fuel metering.
Make sure that you are getting sparks on ALL spark plugs. Bad spark plug caps can cause misfiring. Plug caps should read out around 5K ohms.
I doubt that you have "stuck valves" unless the engine sat for many years in a moist environment with some valves open. Very rare to happen anymore.
You can't get "hotter" sparks. The stock CDI ignition does just fine when everything else is to specifications.
You can have a compression check done to verify that you do have two good cylinders. Compression should be above 150 psi on both sides.
When engines get this old, often times the valve stem seals will harden and the engines will start using oil, which can cause smoke and fuel fouling of the spark plugs in extreme cases. If the engine has more than 50k miles, then the rings may be wearing too, causing more oil usage.
You didn't specify the miles on the engine or any kind of history or maintenance done, so I am just throwing out some of many possibilities.
Bill Silver
