Sounds like part of the sleeve inside your pump let go. Pull the shoe off of the bottom of the pump and you will be able to figure out what broke. The sleeves are replacable and cost somewhere around $40. If it is the impellor I do not know what a replacement aluminum inpellor costs but a new stainless steel one will run about $400. Make sure you put anti sieze on the studs or bolts (depending on if your pump is an old or new model) when you reassemble it. I just had mine apart this weekend to sharpen the impellor. Outboard jet that makes the pumps does not have a website that I can find. You can find out what model pump yours is by looking on the side of the pump, it will have a stamp (old models) or a label plate (new model), yours is probably an "R" model based on the size of your motor.
Good luck and tight lines, Jeff