Dan
Guest
Unlatch rock or trap door and try again. loosen the two 1_2" nuts holding the cast blocks on both sides under the concave a bit and try again. Report back. Concave can be sticking some where it fits into cage but that would be mainly after extended time of non use. There is a bushing that fits onto hex shaft right next to worm gear that can be siezing in adjusting assembly. You may want to mark position of worm gear to hex shaft and then pull it apart to free it up and lube it.