28' Rear Engine Snapper- Will not start

Hello everyone i'm new to the group and was hoping to get some advise on my issue that I'm currently have with my Snapper Rear Engine Rider. The mower has 12.5 Briggs & Stratton, OHV, engine with electric start as well as manual start. The mower is approximate 7 years old so its a REAL Snapper, if you know what i mean. I was cutting the lawn last week and I ran out of gas. I refill the tank with the same gas that i had been using already and now it will not start, either by electric or manual. So i went to action to check out what was happening.. First i thought the unit was getting gas so i pushed it to a level area so the gas could flow down to the carb. Put the unit into chock and tried again, still would not start.. Next step, check the spark, i pulled the plug, connected my spark starter first to the coil wire and to ground.. I had a spark, so that was good, then i connected the spark tester to the plug with the coil wire installed as well and to ground..I had a spark. Tried starting again by electric start as well as manual.. again the mower would not start.. it would turn over but would not start.. So, i check all electrical connections could not fined anything wrong, then i bypassed the safety switches just in case.. and i had spark, I confirmed the switches were working by trying to start the unit without sitting on the seat and of course i had no spark, so i concluded the safety switches are working okay, so now that i have spark, compression, the only other thing i could thank of was the carb perhaps got trash from the fuel tank..so, my next step was to take the plug out again and spray carb fluid directly into the head, put everything back together again and tried to start, and again the unit would not start. Even though the unit would not turn over with the carb fluid I removed carb. anyways to check for signs of trash in the carb.. cleaned and reinstalled.. again the unit would not start.. so here i am asking for your suggestions.. I'm at a complete lost now.. PLEASE HELP..

When you took the carb off was the bowl full of gas?

Yes, i also drained the fuel tank as well, and added new gas again..

Did it backfire when it ran out of fuel ?

Pull the blower cover off and the starter clutch to check the flywheel key

Hello Bert.. it did not back fire but I'll take the cover off again and check the flywheel.. That sounds a little unusual for a flywheel key to shear on a rider.. but at this point i will take all the advise i can get.. thanks for you feed back Bert. I do believe the model of the engine is the 217707 series.

If you are getting spark at the plug, then there is no safety switch in play. Let it sit, take breather off and spray a one second burst of the starter fluid into the carb. It's very easy to flood it by spraying directly into the head. If by chance it was already flooded, it's dumping more fuel along with the raw starter fluid so it will flood even more. Provided nothing mechanical went wrong, if you have fuel, spark, air, you will have bang. If you feel compression when you pull the cord it should be ok. If your tank is empty in the morning then you know you have a stuck/sunk float ;-)

so, i have let the mower set now for a few weeks and it started up the other day but doesnt sound great.. Lots of black smoke, so know i'm thinking its a carb problem. i let it run for a few mins and turned it off, would not restart..

Sounds like it's running very rich and flooding out. Is the choke stuck closed by chance? Maybe the carb float has a hole and is sinking. Also, make sure the vent on your tank is open. If you close it cold, then if it's a hot day, that might be enough pressure to override the needle/seat in the carb and force too much gas into it.

UPDATE: Rebuild the carb. now it runs great.

Excellent!!!