This problem has me baffled. I cleaned the carb, flushed and replaced gas. It starts and barely runs popping and backfiring out the carb. But... If I mess with the throttle and choke long enough (hours or days) it will smooth out and run great for hours. If I cut it off and try to restart it will go back to backfiring.
I put a new carb on it but same still backfires.
A 10 HP WHAT ?? EVERY person on this site that offers help, failed mind-reading ! so in BROAD terms, RE-clean the ENTIRE fuel system, SCUPULOUSLY, next adjust the valves to their proper clearances, ( found in your engine spec. sheets /manual ) check to be sure the flywheel keyway isn't sheared, check all the control linkages for smooth, correct adjustment and operation, and check for frayed, loose or corroded wires.
YOU could post your machines info. and then maybe we could get to the crux of the issue a bit faster, ..see example
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