100 drive shaft spinning

Matt R · #1 11-01-2015, 06:15 PM

Hello from PA.

After reading many great and informative posts for a few weeks I finally have a question of my own. I picked up a '65 100 a few months back to be strictly my snow plowing tractor. She was pretty rough and had not ran in quite some time. Ever since she has been re-running, it would always grind going into gear and the drive shaft would still be turning with the clutch depressed. After noticing the teaser spring broke I decided a clutch rebuild was in order.

I replaced the clutch disk, teaser spring, TO bearing, and refaced both clutch plates. After reassembly i continue to have the same result. If I start the tractor in gear with the clutch depressed all is good. It is when I pull it out of gear, with the clutch still depressed, that the shaft starts spinning. I'm certain the pressure plate is disengaging from the disk while the shaft continues to spin as I can see light between the two. It seems like it is binding in the pilot bushing, yet it is well lubricated. Warped shaft?

Any thoughts? Thanks!

jaynjeep · #2 11-01-2015, 07:49 PM

You must have binding In the pilot bushing... that's about the only thing I could think of if you can see the rear pressure plate moving back.. Bent shaft or improper sized pilot bushing.. I have had to slightly hone the bushings before.. after pressing in sometimes they are too tight..

If the shaft is bent you should be able to see it wobbling at medium throttle..

It may free up with a little use

Good luck

Jeff in Pa · #3 11-01-2015, 07:58 PM

Hi Matt

Welcome to OCC

I'm just south of Allentown

How tight was the driveshaft into the bushing? Was the end of the driveshaft smooth?

When I had my 122, mine was tight like that. I helped it wear in by nosing the tractor up a steep part of my lawn and keeping the clutch in to gain a little clearance.

If your driveshaft is worn, I make new ones out of 4140 alloy steel.
http://www.onlycubcadets.net/forum/s...ad.php?t=20875

Jeff

Matt R · #4 11-01-2015, 08:36 PM

Thanks for your responses, and nice machine work Jeff.

I cleaned the end of the shaft up in a lathe and it slid into the pilot with no hesitation. I was thinking of honing the pilot slightly to get a little more clearance there and I'll check for wobble in the shaft. I was thinking the other day that the shaft would be an easy machining project if need be.

BTW, I'm in northern Schuylkill County.

Thanks again!

Jeff in Pa · #5 11-01-2015, 08:44 PM

Another possibility is the clutch adjustment is incorrect. If you don't have a manual, we have them in the resource section and it will cover correct adjustment.

Matt R · #6 11-05-2015, 07:27 PM

Well, I think I figured it out. After machining a new drive shaft and getting the same result I took a step back to look at the overall picture. It turned out the clutch disk springs were slid ahead on the shafts towards the engine, keeping the clutch disk pulled against the front clutch plate. I slid the springs back towards the disk and no more grinding.

Are those springs even necessary? I reassembled with only one spring. Plus, the new clutch disk has a metal disk between the two fiber disks as opposed to a solid fiber disk that was on before. I would think the metal disk would help with the holes from getting egged out.

jaynjeep · #7 11-06-2015, 08:39 AM

It will work with or without those springs... they are there to keep the disc from rattling or beating against the driver pins.... as long as the disc and driver pins are a tight fit it doesn't rattle too much without the springs.. but as the holes wear a bit it will begin to rattle if you don't have the springs..

glad you found the issue