Lack of water in you engine block. Lack of oil in your engine block. Can cause piston siege.
There is a large bolt head in the center of the crankshaft pulley, if you can get a socket and rachet to fit on bolt( some cars don't allow alot of play room ), try to turn rachet in both directions....
When the engine can no longer rotate.
yes, and it will cause it to overheat and parts will break, dont try it lol. you might make it a mile before your car is done
No, only the compressor will lock up.