If the lure has been crushed by a fish it just needs to have the prop blade readjusted. It helps to have more than one in your tackle box. That way, if one isn't running correctly you can use the other one as an example of how the props should look. If it ran correctly for a long time but now it doesn't, then the prop is probably loose in the slot. Some of mine have a stable and some have a little screw that holds the prop in place. The prop gets loose over time. When the prop is loose and sloppy in the slot it won't run right. I use a good-running lure for comparison and then I set the prop in place and glue it with Gorilla Glue. Gorilla Glue is water proof and it's worked well for me.