Small Engines (Lawn Mowers, etc.): Riding Lawn Mower Craftsman--too much oil, spark plug wire, mouse nest

Question
My husband ran the gas out of our Craftsman lawn mower. He refilled the gas tank but had problems starting it. I suspected there was a mouse nest in the engine and I was right. He pulled off the top and pulled it off and we discovered the wire to the solenoid leading to the spark plug had been chewed through. So I ordered a new part. Now, meantime he added oil (to a hot engine I might add I know stupid). We get the part back add it on, change the spark plug, it sputtered and backfired and wants to turn over but will not. I read many forums and asked him about oil (which by the way he didn't tell me he added). We drained the oil and added new. Still nothing. The flywheel is not sheared, the spark plug is getting spark, the carb float is not stuck and I'm dumbfounded as to what it could be except for perhaps maybe he screwed up the engine. Any advice? Desperate here and really can't afford a professional to look at it. Heck, a new engine is $479 and Sears would probably take advantage of us in servicing it. PLEASE HELP?????  Thank you

Answer
Tammy
Putting in oil really has nothing to do with starting unless he put in more than the recommended amount.Check that first.Next remove the spark plug as see if it is dry. If it is dry take the air cleaner off and spray some Carb cleaner in the carb opening about 1 -2 squirts then try restarting if you get nothing not even a back fire then you may not be getting spark. Check the wire that goes to the solenoid the small wire not the spark plug wire see if that is shorted out,this wire is called the kill wire as it shuts the engine so it wont start.If the engine tries to start and shuts down the carb may be flooded,let it sit until the fuel evaporates, again check the plug if it is wet then it is flooded if not you may have a carb problem if it starts with the carb cleaner.