The inner and outer graphite impregnated cork seal rings were tapered so in theory you could tap the retainer ring in the back and tighten the seal. In practice you go to a bearing & seal warehouse and find a modern seal to fit the shaft, then machine the case cap to fit the seal. The drive shaft seal is the one that gave us trouble. Reaming out for the seal left little material to support the seal. Some creative welding added strength and sealed the cracks. We were then able to use hypoid gear oil for lubrication. If you don’t do the drive shaft seal, run John Deere Corn Head Grease.
