Sounds like maybe a clogged fuel line or a sticking float valve in the carb. Try pulling the carb, blowing out the fuel lines and cleaning/replacing the float valve. (or diaphram valve depending on model...) Get the engine model # off of the block tag plate label thing and you can get the right parts from a lawn mower or small engine rapair shop. Also pull the plug and check that the gap is around .035. (I just returned my mower to the land of the living and mowing
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