B7100 rear PTO seal replacement

[Johan42]

The PTO of my B7100 is leaking oil and I am trying to figure out what it takes to replace the back PTO seal. I cannot find much information on this, is there anyone who can explain?
Do I need to remove the backing plate (the one secured with the 6 bolts)? Or can I just remove the seal from the outside? and how? Do I first need to drain the transmission oil?
Any special instructions on how to move the new seal back in, eg. filling the ring with grease before installing?
Any advise is much appreciated

 

[JKP]

Johan42,
I am in the same boat, just got a new to me b7100dt and after three mows with the finish mower, here comes the fluid. I will be watching your thread for info as well.
Rgds,
J

 

[cabu]

I had the same problem:

http://www.orangetractortalks.com/forums/showthread.php?t=1270

Actually you need to replace the seal from inside. But when I started the job I figured out, that the bearings where used up, the oil was dirty and had a lot of metall parts. And so I brought the tractor to a shop because they have all the spares.
Changing only the sealing is cheap...

carl

 

[Johan42]

Carl, thanks for your quick reply.

I am still a bit confused though, particularly by a posting which I found today on another forum and which claims the seal can be removed from the outside without removing the PTO cover plate: http://www.tractorbynet.com/forums/kubota-owning-operating/116929-b7100-power-take-off-seal.html

I thought it would not harm to give this simple recipe a try. So drained the transmission oil and then removed the seal with a small screwdriver. Unfortunately it did not remove completely, as one can see on the last picture.

So not sure whether the reference above is incorrect, or whether I did something wrong.

Any more advice / experiences are very welcome!

 

[JKP]

Johan42,
While I am still waiting on others to reply, I can tell yo that all you removed was the rubber part of the seal. The rusted circle around the rubber part is the main part of the seal. A new seal will consist of the metal ring with the rubber attached and a small spring looking circle in the rubber part. I am hoping someone will chime in with the answer about replacing from the back without removing the plate. I also saw the article you referenced but not sure if the seal will go over the PTO shaft from the back. Since you are trying it go ahead and remove the metal part and see if you can, you've already removed half.
Rgds,
J

 

[cabu]

After you have allready drained the oil you can also open the cover. It's no magic behind. You can take the gears out with no extra tools, just take them replace the seal and put the two axles back in place. Easy job!!

Have fun

carl

 

[JKP]

Carl,
Thanks for the follow up, after the next mow I will give it a try.
Thanks,
J

Johan,
Looks like it is just as easy to remove the cover.
Good luck,
J

 

[Johan42]

Ok, I removed the 6 bolts and opened the cover. This was actually pretty tough since the plate was glued to the transmission case. Anyway, after carefully hammering it finally came off without any damage, 1 hour later . Indeed no magic behind the cover .. all parts came out easily (Picture #1)

There was a small problem though. One of the ball bearings had a broken ball retainer (Picture #2) and pieces of metal were laying around in the oil. So went to the tractor shop, bought new bearings and replaced the old ones.

The PTO seal which I'd ordered had also arrived so now I could actually see the thing (Picture #3). The rubber seal indeed has an attached metal ring, as described by JKP (note that this is different from the pictures that some webshops show as the PTO seal).

Assembling everything was pretty easy. Pressed the new seal into the back plate. Inserted the PTO shaft (added some grease so the rubber does not immediately get damage). Moved the other shaft back in place. Installed a new gasket. Closed the back plate with the 6 bolds. Added new transmission oil. Etc ... Pictures #5

So ... what have I learned .... the PTO seal can actually be removed without opening the back cover. It is pretty simple: there are 2 notches in the circle on the back plate (the 2 indentations that are lined up horizontally). Put a small screwdriver behind the metal ring and the seal should come out .. Picture #4

As said above I went a different route, opened the case and knocked out the seal from the inside. But I do not see any reason why this cannot be done from the outside. BTW, the guy at the tractor shop confirmed .. just drive the front wheels of the tractor into a ditch (plenty of them here in Holland ) and remove the seal with a screwdriver.. no need to drain the transmission oil ... just a 5 minute job, he said.

But I am happy that I did open it and could replace the damaged bearing.
And certainly an interesting first exploration into the interior my new (1977) Kubota!

 

[bruceatlam]

Nice job! Thanks

 

[fj40dave]

Nice job x2!

 

[JKP]

Johan,
Nice work, and great explanation and pictures. I might try to change it from the outside, if so I will take pics and let everyone know how it works out.
Rgds,
J

 

[bikerdib]

Turns out you are lucky you took it apart anyway. That bearing was about to let go and would probably have done more damage than just the seal.

 

[dlumpy5282]

I think I would take it apart as not that hard or much more work and inspect bearing alot of seals go bad because of bearing wear

 

[JKP]

Dlumpy,
It would appear that I will have no option but to take apart and check everything, my rear plate doesn't have the two indents for a screw driver. Probably better to open it up and check that way I know for sure.
Rgds,
J

 

[cabu]

Yes, it's not a big job to check the bearings, and it is maybe also a good idea to wash out the case to get the metal-parts out of the gear. My case was full of that, with only 850 hours on it.

carl