I have a Model 284h77 Briggs and Stratton motor that won't start. I just had to replace the Magneto, because it had NO spark at all. The new magneto is producing a great spark, but the engine will not start. It seems to try to start the first few turns of the flywheel, but then seemly floods out. I pull the spark plug out and it has gas on it. I have replaced the gas with fresh gas, but still no luck. Any help would be appreciated. Thanks

What about the flywheel key? Have you verified it is not sheared?

I checked it when trying to find the cause of no spark. It looked fine then, but I haven't checked it since I've replaced the magneto. I have thought about checking it again, but I don't really think that's the problem.

Flooding is a typical carb problem. Take apart, clean and re-assemble.