I have a 1992 1660 with 3700hrs and cummins engine. Unload auger just started not folding out. You can hear pump go under load when lever is flipped but won't move. Pushed it out on hillside but still won't go on out. Folds back up just fine. Put new pump on last year and all grease zerks taking grease. Any help appreciated trying to get started cutting corn.