Original post is on the bottom of this page as of 8:45 CDT. It appears that I am not going to get an exact measurement on the backlash of the ring and pinion on my Super A. I can visually tell that it is at least twice the correct value with the original shims--about 0.014 vs 0.005-0.007. I swapped sides, left to right and right to left, a thin shim for a thick one -- now it is too tight. So, I have to take the bearing cages out again and substitute a "medium" shim. I assume that both wear and noise will be worse if too tight rather than too loose. Is this correct?? I'm guessing I can get it to about 0.007. May have to purchase more shims as I am not sure I have all of the 4 sizes, if CIH still makes them. Additional comments are appreciated.
- Thread starter CNKS
- Start date
Janicholson
Well-known Member
Putting it at .007 will be a good compromise. THey will make noise no matter what if they are used gears, and run with the lash close and the pinion depth good. The tooth pattern is more important on used gears than the lash, but with poor visibility the only choice is to be as close as possible. If the gears are 3" and the pinion is ~1.750 in radius at the pinion, an approximation is to double the lash when measuring at the gear. A good pattern is found by putting prussian blue on the gear teeth (pinion or ring) on the driven side, Put a weight or resistance on the ring gear and turn the pinion till the same tooth becomes visible again. The pattern should be centered on the face of the tooth, and blend outward to the edges from there. There are good examples on Google images ring gear wipe patterns. Jim
Jim Becker
Well-known Member
The wipe pattern should be centered between the root and tip of the teeth. But it will be at the toe (small) end of the teeth. A bit of distortion under heavy load will bring the contact point from the toe to the center of the teeth.
Thanks, the service manual shows and explains the pattern. Haven't decided whether to try the prussian blue. But, as you know the backlash is only a starting point, and the prussian blue fine tunes it. The left bearing cage is difficult to remove without messing up the shims. I have already disassembled the thing twice -- could go on forever.
Several years ago I replaced the transmission case on my Cub, so had to reset everything. I think I took the bevel gears apart at least 8 times before I was satisfied with the backlash and mesh point. It one point I was so frustrated I quit and went in the house and worked on it again several days later. I always wondered how they originally did it at the factory. They couldn't have done it by trial annd error. Roger
Hendrik
Member
I did the same on my Super A transmission a couple of weeks ago. Putting the shims back as they were originally, gave a backlash approx. twice as large as specified. So I moved a thin shim from one side to the other, which resulted in the lash being within spec. Using Prussian Blue (the non drying type in a tube, from Permatex) nicely revealed the wipe pattern, which turned out to be as specified. (I observed the wipe pattern on the ring gear (differential) because the wipe pattern on the ring gear is not much different from the wipe pattern in the pinion, in my opinion (no pun intended).
I also wondered how it was done in the factory. If it would involve removing the bearing cariers multiple times and also the pinion shaft (also shimmed!), to me that would seem like a not very desirable job.
HTH, Hendrik
I also wondered how it was done in the factory. If it would involve removing the bearing cariers multiple times and also the pinion shaft (also shimmed!), to me that would seem like a not very desirable job.
HTH, Hendrik
I got it close, finally. I agree that removing installing the carriers is a pain. The process went as follows: 1) Original shims, backlash 2X much like yours. 2) exchange .029 shim with .007, one side to other --extreme overkill, too tight. 3) put .007 shim back on the other side, replace with .014 shim, still too tight. 4) put .007 shim in addition to .014, seems to be ok, including the pattern. Decreased backlash by about .008--it appears a little tight visually, but with no good way to measure it, I'm going to leave it alone.
Hendrik
Member
My transmission case is also sitting on my worktop with PTO removed. I put the transmission PTO-side-up and measured the backlash of the ring gear (pinion clamped tight) with a vernier callipers. If you wish I can take a photo this weekend and post it here or e-mail it to you. (I know the accuracy may be less than with a dial but it works for me.)
By the way, did you modify the shims of the pinion shaft (at the bearing carrier at the front of the transmision)?
Note: I renewed all the ball bearings and the roller bearing in the transmission and differential.
HTH, Hendrik
By the way, did you modify the shims of the pinion shaft (at the bearing carrier at the front of the transmision)?
Note: I renewed all the ball bearings and the roller bearing in the transmission and differential.
HTH, Hendrik
I'm replacing the bearings as you did. In my previous response I said I thought I had it fixed, now it seems too loose. I have a 0.004" shim ordered from CaseIH, may not get here until Wed. If you don't mind, you can send me a picture at [email protected]. Not sure I understand how you got calipers in to measure the backlash. The only way I see to get anything in is to remove the 4 differential gears, then it's a long reach. I did remove the thinnest shim from the front of the countershaft. It seemed to make it too tight, so I put it back. But, I'm not sure of that either, as for whatever reason, I did not get the front bearing seated right. Had problems after I put the shim back in. I drove it in with a hammer and socket on the inner race, I did not do that with one shim removed, that might be why it was too tight. And, the book says the ring and pinion are supposed to be flush at the big end of the pinion (front end). I cannot see that as the housing is in the way. The small end appears flush. So, I'm still messing with it. This is the one thing I have to get right.
Similar threads
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