Taylor87
Have checked the fuel pump? You can test it by disconnecting the fuel line from the pump to the carb. You'll need to capture the fuel coming out of the pump, so put the hose in a plastic bottle, seal it so it can't spray out on you.
Have someone turn the engine over with the starter and see how much fuel is being pumped and if it look consistent.
The stumble sounds fuel related. If the float level in the carb is too low, it may be running out fuel at the metering jets, the mixture will go lean. If the float level is too high, the float bowl will flood and the mixture will be too rich and choke the engine. Have you pulled the spark plugs to see if they are getting a lean mixture (white-ish color) or a rich mixture (black carbon color)?
If we can eliminate the fuel mixture issue, then we only have spark, or possibly a more serious mechanical issue.
Is the gas fresh? .... not really old fuel?
I'm just thinking out loud.
Gnarls.
![In The Dark :inthedark:](https://board.marlincrawler.com/Smileys/marlin/inthedark.gif)