I am working on a 853H, the left rear wheel is not being driven. I pulled the covers and jacked that wheel up and gave it a spin. Everything spins except the sprocket. Seems the bolt requires a 1 1/2 inch wrench, no room for a socket. I have my open end wrench with a 3 foot pipe on it and no luck loosing it. Anybody ever did this and what did you use? Thanks