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Gas Leaks In Right Cylinder

694 Views 5 Replies 3 Participants Last post by  66Sprint
I left the petcock on my cm400t for a few days and found that though it was leaning left on kickstand gas had filled the opposit cylinder and I had to remove plug to let out the gas cause of pressure buildup so that it would turnover and start..
My first thought is float needle isn't seated or intake valve isn't seething. I recently adjusted valves gaps too proper specs.
Any other possibilities I might have overlooked?

Thanks
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The float valves provide an imperfect seal. It is common for some fuel to seep past and overfill the carbs allowing fuel to flow down the carb throat, past an open intake valve, and into the cylinder. Some of this fuel will get past the rings, into the crankcase, and dilute the oil. It takes only a small amount of fuel and a short time to trash the engine.
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