Craftsman rider electrical problem - won't start or turn over, just clicks

[mskaling]

Mower started and was mowing just fine. Turned it off to dump bagger, and now ignition just "clicks" when key turned. Battery is charged and terminals clean.
Vintage is about 2001, 16 HP OHV Briggs. Never had a problem before. What/how to check??

 

[ILENGINE]

attach meter to both terminals on the battery, and attempt to start. What is the voltage.
Move the red lead to the small terminal on the solenoid, and the black still on the battery ground. attempt to start, what is the voltage.
Now move the red lead to big wire on the starter. What is the voltage.
Last put the red lead on the metal part of the starter, what is the voltage.

post back your results, and we will know were the problem is.

 

[mskaling]

Thanks for the good advice which I'll print and keep, but hopefully won't need it.
Turns out the engine was "stuck". I put a prybar on the fins of the flywheel and
got it to pop loose, everything is just fine. Can't help wondering what causes
such an event. Oil was not low. I am happy camper.