Hi Merv, I'm not sure if you were able to get the sprocket off. If not there are about a dozen or so 12mm bolts to remove the sprocket. The sprocket itself does not have any seals. Behind the sprocket is the torque hub, then a multi-disk brake and finally the hydraulic drive motor. If you are trying to get into the torque hub, everything else has to come off first, then unbolt the torque hub from the frame (those giant nuts just in front of the torque hub). Let me know if you need a diagram for any of it.