Guys I have a Craftsman rider about 2 years old and use it almost everyday around the house.

Went to start it yesterday and think I heard an internal backfire. Meaning not loud, but internal. It would not turnover after that.

I turned engine by hand and it would only go so far and wouldn't go past that point. I thought about pistons rods bending or valves being stuck and took out the plug and it turns over like normal. Put plug back in and same issue. Do I have a bent rod or which way should I go? Have pretty good knowledge, but not expert

 

Welcome hwills,
A moderator may likely move your post to begin a new thread since this one is going on two years old.
In regards to your problem:
If you remove the spark plug and turn the engine over by hand, can you see the piston moving up and down. You can use a pencil or some such in the plug hole to feel the piston.
If the piston is moving, you can check for compression and vacuum by plugging the spark plug hole with your finger and turning the engine by hand.
If all that checks out, check the oil level, if overfull or smells of gas it should be changed, then, with the spark plug removed spin the engine and see if any fluid expels. If so crank the engine being aware of the spark plug wire sparking and keep it out of the line of fire until any fluids quit coming out. Then try it with the plug in again.

If none of that helps, then post back with model # preferably of the engine.