Small Engines (Lawn Mowers, etc.): Ranch King wont start, amp fuse, starter solenoid

Question
My dad's Ranch King model # 168971which is  18.5 HP and a 46" cut will not start.  It was running great and I shut it off, tried to start it a minute later and NOTHING.  I charged the battery, nothing. I replaced the battery, nothing.  I could only find one blue 15 amp fuse and it was good.  I cleaned the connections at the battery, starter and the ground, and still nothing.  It seems as if a safety or something is not being DE-activated, not allowing it to start.  When you turn the key and hit the BRAKE/CLUTCH, it doesn't do anything.  Please help.

Answer
Is the mower in reverse by any chance? Or are the blades still engaged? Check the seat safety switch. If all your safeties are working correctly, check the starter solenoid. Run a jumper to the starter to make sure the starter is good, and the engine didn't seize up. ....Tom