Small Engines (Lawn Mowers, etc.): craftsman wont start., neutral safety switch, jumper cables

Question
have mid 90s craftsman. took mower deck off as it was rusted out , replaced it with another. now it wont start. It wont even turn over. I can put jumper cables straight to the starter and it will crank all day but will not fire. I dont believe I unhooked any wires while changing deck. What should I check?  

Answer
 Hello Bill:

 Send me the Model Numbers Off of the Mower and Off of the Engine, Please. With these I can Locate a Breakdown of the Mower and Engine and Better Assist you. However, Check the Seat Safety Switch, the Neutral Safety Switch, Clutch/Brake Safety Switch and the Blade Safety Switch. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John