(800) 853-2651
SHOP NOW

Clutch problem

M

Mile high Steve

New User
Hello everyone. I am new to this forum so hope someone can help me with a problem I am having. I purchased a 1949 farmall cub and decided to replace the clutch because the old clutch would never disengage and so even when the clutch pedal was engaged the gears would always grind when shifting. I just installed a new clutch and adjusted it according to the manual but the problem still remains. Even when the clutch pedal is all the way in the drive shaft is still engaged. There is 1" of free travel and 1/8" between the throw out bearing and clutch fingers. I even had a friend who has replaced hundreds of clutches help me and he is as much at a loss as I am. Any ideas on what could be wrong?
 
Do they have a pilot bearing or a bushing? Sounds like whichever one it is,it's hanging up so the shaft continues turning.
 
I would have to agree that it is probably the pilot bearing. I have a Farmall Regular that had the problem, I stopped counting how many times I took apart the clutch
because it wouldn't disengage to shift and nothing I did worked and then I noticed that the pilot bearing wouldn't spin freely. After greasing it and oiling it a lot, I
was able to get the tractor in gear, push the clutch in, and apply the brake which then loosened it up. See if getting it in gear and pushing the clutch in and applying
the brakes does anything. I will have to replace the bearing, but this can at least help confirm that it is the problem.

~FarmallCT
 
pilot shaft that enters into the pilot bearing of the crank is bad,dry or gummed up and it drags therefore the shaft doesent stop when the pedal is depressed
 
it is a brass bushing in the crank and care when installing by using a bushing driver so you dont flare he bushing as that will cause it to drag the main shaft so it doesent stop when the clutch is pressed.
 
Low oil level (and or wrong oil) in the trans will fail to slow the shaft to allow shifting. If the trans has 90wt in it to
the mark, pilot bearing is it. Not a bad job, but repeats most of the work done. Jim
 
Besides the pilot bushing, which has been mentioned previously, a bent transmission shaft will cause that. Also if the clutch fingers are not adjusted evenly.

Next question, did you replace the throw out bearing, which is actually a graphite bushing. If it is worn off it may not be traveling far enough to release the clutch. Also, many places claim the fingers are preadjusted, but a cub uses a different adjustment than other tractors, and the supposed preadjustment is not right.
 
Like others said, could be the pilot bushing.

Also, when installing the pressure plate bolts, they need to be pulled down evenly so not to warp the pressure plate.

When stabbing the engine back onto spline shaft, it is important not to force the two together. When everything is right, they will go together without the use of bolts. Also want to keep the weight of the engine from hanging on the clutch and transmission shaft. That can warp the clutch disc and or bend the spline shaft.

You might can cheat a little on the freeplay clearance. As long as the release bearing is not riding on the fingers you can decrease the clearance to get a little more throw. It might get better as the disc compresses and the fuzz wears off.
 
The clutch disc could be in backwards-the thicker side of the damper springs goes to the rear.When you depress the pedal,can you get into gear at all?If you put it in gear with the clutch depressed,and then start the tractor,does the tractor try to move?If not,you may not be waiting long enough for the transmission to stop rotating when shifting.Otherwise as others have said,pilot bearing seizing,bent disc are posibles.Mark
 
hold on, the way this is worded, just hit me, he says it grinds when shifting, to clarify you are meaning the transmission grinds when you depress the clutch and put the tractor in gear while its sitting still, right? what rpm is the engine at, my cubs are both testy about that, you have to idle the throttle depress the clutch wait a few seconds then feel the stick into whatever gear you want to use, also cubs, like most old tractors are not meant to be shifted while rolling, the tractor must be at a stand still
 
(quoted from post at 17:01:43 05/16/16) Do they have a pilot bearing or a bushing? Sounds like whichever one it is,it's hanging up so the shaft continues turning.
Click to expand...

Thanks to everyone for the good information. The clutch was preadjusted and I did not check the adjustment because it looked right. l'll recheck that. I did replace the graphite throw out bearing but used a thrust bearing from Yesterday's Tractors instead of the graphite bearing. A brass bushing is used for the pilot bearing and the clutch pedal was adjusted as per the manual. From what everyone has said it sounds like the problem could be in the pilot bearing/bushing. Thanks to you guys I have something to go on and I'll let y'all know what happens.
 
The pilot bearing could be seized if you are shifting properly. Did you check to see if the pilot bearing slid easily on the input shaft prior to installation? If you didn't did you "pull" the transmission to the block? Transmissions need to be "pinned" to the block and bottomed prior to starting any bolt.
 
i'm gonna bet it's the pilot bearing, had a 530 case do the same thing. we thought it was the clutch too.....
 
A friend has an AC B which he had to shut off to shift since he bought it(well used)! Everything looked good, and was adjusted correctly. I watched the action up through the hole as he exercised it running. I finally noticed the pressure plate cover assembly flexing. I can't remember if the springs were bottoming out, but we eventually figured out someone had put the wrong springs in it. I don't recall if they were longer, or heavier. I believe they were WD springs.
I had another one once baffle me, and found the worn pilot bushing was apparently letting the shaft wobble around a tiny bit, which apparently was letting the clutch drag a little. A new pilot bushing solved that one. Kind of the opposite of what I thought would happen.
Some of the old engines had a felt wick through a hole in the back end of the crankshaft to lubricate the pilot bushing.
 
(quoted from post at 04:13:09 05/17/16) The pilot bearing could be seized if you are shifting properly. Did you check to see if the pilot bearing slid easily on the input shaft prior to installation? If you didn't did you "pull" the transmission to the block? Transmissions need to be "pinned" to the block and bottomed prior to starting any bolt.
Click to expand...

The pilot bushing was placed on the input shaft with no problem. When we recoupled the tractor we brought it together to within an inch and then used the bolts to help line it up while we pushed both ends together. Interestingly enough the tractor was doing the same thing with the old clutch and its pilot bushing was worn to a nub, but it also had a bad clutch finger. We're going to get back into it next Monday and see what we can find. I'll let you guys know how that works out.
 
As promised I wanted to let everyone know how my clutch problem worked out. As all of you thought -
it was a problem with the pilot bushing. I found this to be true by carefully splitting the tractor
approximately 3/8", starting it and finding that I could now operate the clutch and move through the
gears with no problem. I then split the tractor the rest of the way and checked the pilot bushing.
What I found is that I had not driven the bushing in far enough. I finished seating the bushing, put
the tractor back together and the clutch now works as it should. I want to thank all of you for your
advice. I never would have thought to check the pilot bushing.
 
You must log in or register to reply here.

Similar threads

U
MF 35 Clutch Problem
Replies
8
Views
262
Uncle Fred 02
U
B
John Deere 2020 PTO Clutch Adjustment
Replies
13
Views
538
Tx Jim
Tx Jim
M
JD M Clutch Grinding
2 3
Replies
47
Views
2K
Janicholson
Janicholson
Ellis Kinney
Truck clutch
Replies
7
Views
522
mechanicfred
M
G
Replace clutch assembly on 8n
Replies
12
Views
458
Myold48-49#
M
Tractor Parts Tractor Manuals

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top