I have a yard man riding lawn mower. One day while using it, it did a big surge and I fell off. I had to push it back down because it was sitting up on its two back wheels, now it will not start. I tried to change the spark plug and tried the battery but nothing works. Please help

Make sure it is getting spark. Cycle the piston when you remove the spark plug. What size is the engine HP? Does it have a pull start? What does it sound like when you turn it over. Need more info. Over head cam? B&S or Tech. will get back. Thomas

It is not a pull start. When I turn the key nothing happens, it does not make a sound.