The auger on my 21" Yard Machines Snow Thrower broke. I ordered a new one (without the rubber pads) and I'd like to put it on, but I can't dissassemble the old auger. The only two pieces that I can't remove are on the left side of the machine, under the drive flywheel. They are both free-spinning metal parts. One is like a cylindrical ball bearing, the other piece is a thin metal washer (approx 2" diameter). They both sit right next to each other. How can I take them off?