Hi Alan, Peter is going to list his better replacement parts.? ?(He also has found an 80:1 gearbox that is not marketed by McLennan..it comes from vendor RS Components.? ) To get to the ring gear: On a G11 or GM8, you? 1. remove the bottom clutch knob and it's flat thrust needle bearing assembly.? (Put those parts in a plastic bag).? 2.? pull out the 1.25 inch shaft as though you were replacing the clutch disk. 3.? To remove the upper ring gear, you must back the worm threads away from the ring gear teeth. (on a GM8 drive you'd have to remove the worm to get the worm sufficiently back from the ring gear.) 4. Lift off the ring gear.? Actually, before you lift it off, you should see if you can lift it up slightly.? If you can lift the ring gear up with the worm still fully engaged, it could mean the worm center is slightly higher than the ring gear center.? If the center of the worm axis and the center of the ring gear heights were absolutely at the same level, (or the ring gear center is higher than the worm center so the worm is riding on the ring gear teeth below center of the ring gear) the ring gear should be trapped by the worm threads.? ?I hope this makes sense!? If the ring gear needs to go higher to be centered, you will need a thicker upper race washer or (as Peter discovered) a new flat needle bearing with slightly larger rollers.? McMaster-Carr sells many different thickness race washers. Peter found that a new needle bearing but same races put his ring gear at the optimal height for his DEC worm.?? 5. Under the ring gear will be the flat race washers with the flat needle bearing sandwiched between those flat race washers.?? ? ?a. There will be a thin flat race, and a thicker flat race.? ? ?b. The thin race washer goes underneath (closest to the clutch knob at the other end).?? That's all...from memory.?? Once you take off the upper ring gear you will see the internal cylindrical needle bearings holding the 1.25 inch shaft in place. I was told that the needle bearings can be tapped out to replace them, using a wooden dowel on the G11, but on my GM8 axes, I can't see how to get those bearings out or to put new ones in. If someone knows, please advise how to disassemble the GM8 axis body.? Best, Michael On Tue, Jul 20, 2021, 10:26 PM alan137 <acfang137@...> wrote: How does one get to the thrust bearings? |