QuestionQUESTION: I have a craftsman 16.5 HP Honda engine that is backfiring through the carburator. The carb was cleaned, new plugs put in but still backfiring and plugs are black carboned up. Anyone know the cause?
ANSWER: You probably have an air passage in the carburetor body that is plugged up causing the carburetor to flood. The plugs being sooted up indicates flooding. I suggest purchasing some Deep Creep and spraying it in ALL passages and allowing it to soak for a while, then blow it out and try. If this doesn't work you either need it cleaned professionally or replaced.
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QUESTION: Since I had the carb cleaned, I wondered if I should be looking at the timing or valve clearance. Please advise your thoughts.Would a compression check tell anything?
AnswerTiming is completely controlled by the flywheel key, and this shouldn't cause flooding, the same with valve clearance. I really believe you have a carburetor problem, even though your carburetor seems clean, it's not what you can see that is giving you problems, it's what is in those tiny ports you can't barely see.
