Just bought a 9760 started it up and it seems like the primary countershaft gearbox shakes pretty good. Took the clutch and pulleys off, and it seems like the primary shaft is loose in the gearbox. Anyone ever encounter this?
The shaft is splined in the gearbox. There is a grease zerk not shown in the book behind the pulley. Maybe try to grease it and it will grease the splines. Try it and see if it helps. I don't know if it will take care of the shake or not, but the splines probably won't feel so loose and they won't wear as fast. Also see the maintenance and repair tips post towards the top of the page. They offer some information.
The shaft will be loose in the splines with the electric clutch removed. Look on the back of the electric clutch at the hub it should have a nice smooth taper to it. Also the primary countershaft gearbox should have a nice smooth counterbore to it. When you tighten down the clutch the bevled edges seat into one another and center the shaft in the splines. I have had a few nuts come loose and ruin the hub in the electric clutch which is replacable. Also with the separator engaged and the engine at idle look at the electric clutch to see if it is wobbling it it is then the shaft is bent. I have had a ton of 9760 shafts bent. And another thing like jb77 said make sure the grease zerk behind the clutch is greased. There is a groove on the backside of the primary countershaft gearcase and when full there should be grease comming out of it.
Here is my experience. I thought I had a bent shaft since the electric clutch wobbled a lot but it turned out the clutch hub taper had worn itself into an egg-shape and was seating into the tapered gear crookedly. New hub, no wobble. I actually took the shaft out to replace it but it had very little runout. So, you might try getting a new hub and torquing it down, then run it some to see if it stops the wobble before dismantling. I am planning on running the machine in the field to get it hot and then retorque the nut.
Not likely your problem, but we have also changed a few steady bearings in the driveshaft to the primary countershaft gearbox. Just something to be aware of, they will look fine, grab on the shaft and see if the bearing moves in the rubber block.
Just to let you all know you don't have to replace the entire clutch. You can get the hub seperate through Deere and I can get the bearing from an independant source. The new clutch is $1160 and I can get the bearing for around $125 and the hub is $435. That is if the clutch facings are ok.