[meimk]

My guess is that it's still not really "running", but rather turning over on the starter. 1) Make sure it's actually got spark - either a spark tester or loose spark plug on the wire touching engine ground and look for spark. 2) If you get spark, make sure the carburetor butterfly is actually opening. I know you said you've tried spraying into the carb, but if the throttle plate doesn't open it still won't get enough air & fuel to run. 3) If all that checks out OK, then it's time to test compression.