We're getting spark, adjusted valve clearance, cleaned the carb, the timing marks line up w/ the "T" on the flywheel and the mark on the cam sprocket w/ the mark on the casting on the case. We can put starting fluid and/or fuel in the sparkplug hole and nothing at all. Blows out the exhaust and sparkplug hole when turning over. No popping, backfire or anything. Does anyone have any idea? Bent intake valve????? Thanks!