How to check pilot bearing?

Dave Downs

Active member
This is a continuation of my clutch free play problem which is now fixed.

The input shaft and gears still spin with the clutch depressed resulting in a gear clash when putting transmission in gear.

The mower deck is off and with the engine off I can put the PTO in gear, push the clutch in and easily turn the shaft with the pulley. With engine running, PTO in gear when I push the clutch in the PTO continues to turn but I can stop it with my bare hand.

The only thing I can think of is a lightly ‘dragging’ pilot bushing. Bushing is a year old old but maybe I scored/damaged it when I put the tractor back together.

Any ideas before I split the tractor?
 
Hi,
Good that you got the free play set better.
Here is some pilot bushing info.
One of the experts on here has said that if the older clutch pilot bushing it has measures ok, and it looks in good condition, it doesn't need replacing.
If you replace the pilot bushing, after putting it in the crankshaft hole, be sure to measure it's ID with a dial caliper before putting the pressure plate on the flywheel.
If the clearance is too small, the bushing needs reaming to make it bigger.

The pilot bushing ID can shrink after driving it in the hole. Then if the bushing ID is too small, and you put the Cub together, the clutch shaft won't stop turning when you push the clutch pedal down.
Then the gears grind when trying to shift them.
Below is a page from the Cub service manual, showing the running clearance for the pilot bushing, at Spline and clutch shaft.

http://farmallcub.com/rudi_cub/www.clea ... -05-02.jpg

If the bushing is too small, it needs reaming.
 
Glen-
Thanks for the info, I’m afraid that I’m trying to talk myself out of splitting the tractor……even though I know I have to !!!!!!
 
staninlowerAL":13gr133g said:
Sounds like you can possibly "wear" the pilot bearing in like someone posted in the past. Try a search to find the posts. Stan

Thanks, definitely going to look for that!!
 
I bought a BN that had the same problem your describing.

It had a bad pilot bushing

Put a new one in and problem solved.

I can not remember if the Cub's flywheel is recessed where the clutch is or not.

But on the BN the flywheel has a recess where the clutch fits.

In my case when you depressed the clutch pedal then the clutch was not held centered, but then wallered around bouncing off the sides of the recess in the flywheel keeping the input shaft spinning.
 
Hi,
The Cub clutch disc isn't recessed into the flywheel, it is slightly above the surface where the pressure plate bolts are.
Below is a picture from TM Tractor. :)
 

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many times a new bushing needs to be reamed/honed as they are to tight, many just install it without checking it
 
If you can stop the rotation with your hand, it could be just a SMALL burr or SLIGHTLY too tight.
I had one that I kept the PTO engage during start (no mower/belt on that tractor) so I could tell when the shaft was still turning after the clutch was depressed. I had a piece of wood and could reach back and stop the rotation, and then engage the transmission without grinding. It eventually "reamed" out the needed amount in that bushing. Not the best solution, but I really didn't want to split the tractor!
 
I had one that was that way after replacing original engine with combine engine. I chained it to my H and blocked the clutch down on the cub, put it in third gear and let ti run at idle for half an hour. Problem solved.
 
if you can spin the imput shaft easily while the pedal is depressed the bushing is not the problem, possible bad pressure plat or the fingers not being set to 1 1/8"
 
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