Differential set up & tooth pattern

Farmall Cub Forum -- Questions and answers to all of your Cub related issues.

Moderator: Team Cub

Forum rules
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.

Differential set up & tooth pattern

Postby bob in CT » Fri Mar 19, 2010 6:17 pm

I thought I would post a picture of what a good tooth pattern looks like. If you replace the ring and pinion, you need to check the set up with marking compound.
I replaced the entire gear set from another box, in this case a Cub Cadet, so I was starting from scratch. The goal was to keep the original casting date transmission with the tractor

To do this set up the ring and pinion with the as close to the original shims as possible and measure the backlash in the ring gear. Use your hand in the transmission to lock it in place as you don't want any slop when you rock the ring gear. You are looking for .002 to .005 so you need a dial indicator.

If the lash looks good, then mark the pattern by painting a few of the teeth on the ring gear and with one hand put some drag on the ring gear and then rotate the transmission for several revolutions. If the pattern is in the middle, like this you are good to go. If this pattern was on the top of the tooth, as this one was, then the pinion needs to move back, so a shim needs to come out of the pinion shaft at the front of the box. Then you need to re-set your lash. Assuming your preload was properly set up, you need to remove a shim from the right and put it in the left side to loosen the lash. Once the preload is set you can move shims from one side to the other but you can't remove any shims.

Image
User avatar
bob in CT
Cub Pro
Cub Pro
 
Posts: 5239
Joined: Thu Jun 07, 2007 9:34 am
Location: CT, Manchester
Zip Code: 06040
Tractors Owned: 77 Cub (red); 74 Cub; 52 Cub; 50 Cub ( post-demo)
Circle of Safety Award
Circle of Safety: Y

Re: Differential set up & tooth pattern

Postby cowboy » Fri Mar 19, 2010 6:45 pm

Great job Bob :{_}:

It takes time and patience to get it right.

Billy
Take care of your equipment and it will take care of you. 1964 cub. Farmall 100 and 130.

"Those that say it can’t be done should not interrupt the ones who are doing it.”
User avatar
cowboy
Cub Pro
Cub Pro
 
Posts: 3414
Joined: Sat May 15, 2004 11:10 am
Location: MI, Britton
Zip Code: 49229

Re: Differential set up & tooth pattern

Postby dakcub » Fri Mar 19, 2010 7:08 pm

Very well done......should last another 6o years....
Robert (never done that job) Miller
dakcub
5+ Years
5+ Years
 
Posts: 1964
Joined: Fri Dec 26, 2008 9:28 pm
Location: CA, Bakersfield
Zip Code: 93313

Re: Differential set up & tooth pattern

Postby Boss Hog » Fri Mar 19, 2010 7:46 pm

Just to add one thought, if you are using old gears, if at all possible use the same shims that the gears came with. The gears will be worn to riding in a certain place. If you have to use different shims you stand the possibility of having some gear noise.
just because the bears are meshing good that does not mean they were riding in the same place originally. Most of the time if it has noise from this issue it will be in high gear when the ring and pinion are turning the fastest.
Boss
IN GOD WE TRUST
All others pay cash
Boss Hog
Power corrupts; absolute power corrupts absolutely byJohn Emerich Edward Dalberg
User avatar
Boss Hog
Cub Pro
Cub Pro
 
Posts: 9836
Joined: Mon Oct 24, 2005 8:35 pm
Location: VA. Randolph
Zip Code: 23962
eBay ID: dmb2613
Circle of Safety Award
Circle of Safety: Y

Re: Differential set up & tooth pattern

Postby bob in CT » Fri Mar 19, 2010 8:00 pm

In my case the gear set came from another casting and I did not take it apart. If I had, I would have measured the lash and tooth pattern before it came apart to try to duplicate it. I think the gears and bearings are made to a high tolerance and the variation is probably coming out of the machining of the casting. So you probably want the shims to follow the case as a baseline but the lash and tooth pattern from the donor gear set. If that makes sense.
User avatar
bob in CT
Cub Pro
Cub Pro
 
Posts: 5239
Joined: Thu Jun 07, 2007 9:34 am
Location: CT, Manchester
Zip Code: 06040
Tractors Owned: 77 Cub (red); 74 Cub; 52 Cub; 50 Cub ( post-demo)
Circle of Safety Award
Circle of Safety: Y


Return to Farmall Cub

Who is online

Users browsing this forum: No registered users and 5 guests