Jumped Timing Chain?

On a motor with a trashed/worn chain...you can easily, sometimes by the belts, move the crank back and forth...the more back and forth it has till you feel it grab the gear, not good ..if you can do this, you'll easily be able to determine wether or not the chain and gear are done and it has indeed jumped. The cam gears are a nylon type to be silent and they're absolute garbage.