I have replaced the vertical unload auger on my 9750sts, when I test ran it the auger started rubbing on the top gear case. I ran it backward by hand and the auger lowers to the original position. then I ran it the correct rotation by hand and it climbs up to the top gear case. What is causing the auger to climb up to the top gear case? It is not rubbing in the tube, when I run it back wards it works perfect. It is correctly timed to horizontal auger.