B7800 Front Axle Rebuild

[Jdmiller17]

Hello all, I知 extremely new here. I知 having trouble finding a service manual download or any solid information on rebuilding the front axle on a Kubota B7800. It痴 for a farm I work at and it has the front loader attachment. The problem was the 4x4 went out in it. The front axle still goes but it won稚 work under any type of load other than just driving around. I pulled the dipstick for the axle case and the gear oil looked like antiseize it was so full of metal. So I figured I would break it down and rebuild it for them. I致e built truck diffs a few years ago but I知 not sure if the tractor front end would be the same. If anyone has any info or links it would be greatly appreciated. I知 sorry if I posted this in the wrong place or if there already is a thread for it. I just couldn稚 find anything. Thank you all for your time.

 

[Thomas]

https://apps.kubotausa.com/illustrated-parts/

 

[rScotty]

https://apps.kubotausa.com/illustrated-parts/

Kubotas parts website doesn't work with some browsers. It doesn't work with most Mac OS, for instance.

Messicks.com has full illustrated parts diagrams for every system on the B7800 along with part numbers, a short description, and price.
You will have to sign up with their site to use that feature, and unfortunately signing up and logging in is probably the weakest part of their website. But worth the struggle.

 

[rswyan]

Kubotas parts website doesn't work with some browsers. It doesn't work with most Mac OS, for instance. ...

If you turn on the Develop Menu (bottom of the page in the "Advanced" pane of Preferences) and then set Safari's User Agent (what it identifies itself as to websites you browse) to some flavor of Internet Explorer, Kubota's website will work.

At least it did the last time I checked.

 

[rScotty]

If you turn on the Develop Menu (bottom of the page in the "Advanced" pane of Preferences) and then set Safari's User Agent (what it identifies itself as to websites you browse) to some flavor of Internet Explorer, Kubota's website will work.

At least it did the last time I checked.

Well, thanks for that. I didn't know about the User Agent, although once I read up on a the function of a User Agent it all began to make sense.

Then I had to go looking for my agent....

In fact, the new Catalina OS for Mac has hidden the User Agent yet again. Preference's "Advanced" now allows "Develop" to be visible only when the box is checked to place Develop on the menu bar. Checking the box then places "Develop" on the menu bar next to "Window". On the Menu Bar I then selected "Develop and after that User Agent (the second choice) and an additional menu told me that I was in the default or "automatically chosen" mode. That's fine most casual browsing, but apparently the Kubota site isn't yet set to trigger the automatic chooser, so I gave it some help by manually selecting " FireFox - mac OS" as my User Agent while I was at the Kubota site. And after a few seconds of self-adjustment I was able to select from Kubota's models and view their parts illustrations and numbers. Wonderfully convenient.

For anyone doing this, don't forget to put the User Agent back to the Automatically chosen mode when exiting Kubota's site.

Thanks again for the hint.
rScotty

 

[moship]

You might want to purchase the workshop manual. Please verify this is the correct manual and latest version before purchasing.

Kubota: B241?/271?/291?/78?? WSM, Part # 97897-12271

Kubota: B2410/2710/2910/7800 WSM
Part Number 97897-12271
Vendor Kubota
Messick's Price $111.04
Stock Quantity 0
Classification Kubota B-Series Shop Manuals
Weight 0.00 lbs
Days to Order 7-10 business days
Replaces 9Y011-13031, 97897-13030, 97897-12270

 

[Jdmiller17]

Thanks for the info guys. I have a copy of the workshop manual but its a little different when it talks about setting it up. It has a setting the backlash section with a level type dial gage but from what I’m used to with the truck differentials we just painted the ring gear to get the correct pattern. Could I do the same? Or is it completely different? I want to make sure I do this right so I do not shell out the diff again as soon as I run 4x4 again. Has anyone rebuilt the front axle before?

 

[orezok]

I would follow the WSM. The manufacturer usually knows the best procedure for their product.

 

[rswyan]

Well, thanks for that. I didn't know about the User Agent, although once I read up on a the function of a User Agent it all began to make sense.

Then I had to go looking for my agent....

In fact, the new Catalina OS for Mac has hidden the User Agent yet again. Preference's "Advanced" now allows "Develop" to be visible only when the box is checked to place Develop on the menu bar. Checking the box then places "Develop" on the menu bar next to "Window". On the Menu Bar I then selected "Develop and after that User Agent (the second choice) and an additional menu told me that I was in the default or "automatically chosen" mode. That's fine most casual browsing, but apparently the Kubota site isn't yet set to trigger the automatic chooser, so I gave it some help by manually selecting " FireFox - mac OS" as my User Agent while I was at the Kubota site. And after a few seconds of self-adjustment I was able to select from Kubota's models and view their parts illustrations and numbers. Wonderfully convenient.

For anyone doing this, don't forget to put the User Agent back to the Automatically chosen mode when exiting Kubota's site.

Thanks again for the hint.
rScotty

You're quite welcome ... :thumbsup:

 

[rScotty]

Thanks for the info guys. I have a copy of the workshop manual but its a little different when it talks about setting it up. It has a setting the backlash section with a level type dial gage but from what I’m used to with the truck differentials we just painted the ring gear to get the correct pattern. Could I do the same? Or is it completely different? I want to make sure I do this right so I do not shell out the diff again as soon as I run 4x4 again. Has anyone rebuilt the front axle before?

Since the whole idea of setting engagement with backlash is to get the correct pattern, I'd go pattern over backlash. Now I've not done an an axle in the last few decades so I may be mis-remembering. But when I used to do that, I would use blue dye on the faces and a dial gauge as well. I tried to get an average between the two, but favored the pattern as long as it was close enough to the recommended backlash to make me feel good about the clearance.

Just writing about this brings back memories. I still like to open the box and look at that dial gauge. It's a Starrett, and just opening up the case takes me back to my youth and how proud I was when I bought my first mic and first dial indicator. Still have them...and now I have my father's as well. Sometimes finding a smooth surface for the lever to run on is a problem. Especially if there has been some rust inside. But you can get close enough.

I don't remember having a problem with bevel engagement that I knew or heard about. So either I got it right or they are exceptionally rugged. Maybe both. On diffs that use shims to set clearance, I almost always eventually ended up using the same shims that were in it to start. I finally got to believe that when re-using the same shims didn't give me close enough to the correct setting, it was time to take it back apart and see what was causing the problem.
rScotty