icemaker continues to run!!

The ice maker on our refrigerator has been a pain since we bought the fridge 5 years ago. It continually freezes up in the ice tray and wont dump the ice. I usually have to chip the ice out and then hold down the on button to get the ice removal device to spin through the ice tray. After my latest round of doing this, the icemaker now continually spins and adds water. I watched it go around 3 times nonstop before i finally shut it off. Any suggestions?
Thanks, Bob