Need advice please on leaking axle

[sgtboz]

Alright, gents...where to begin? It's just a dribble but I know these things don't tend to heal themselves. I've seen lots of references to the commonality of axle leaks but no guide on what it looks like during the tear down. Do you happen to know of any? I've replaced lots of seals on brush hogs and other implements, but nothing along these lines. Any general tips or advice before I start unbolting things and making a mess?

Wouldn't you know this happened right before I planned to sell the thing!?

 

[North Idaho Wolfman]

That seal is an easy fix, get the WSM and jump in and do it.

 

[MikeyA]

Re: Small leak on L3940 front axle

I replaced one on a B2400 a couple of years ago and it is actually pretty simple. A good pair of snap ring pliers is a must. I used some Permatex Ultra Gray to reseal the outer hub to housing. My seal had 2 pieces, and I didn't realize that the collar that seal rides on must be removed from the upper part of spindle before you can reassemble. Even the workshop manual was not clear on this when I disassembled it. If you take your time, it probably won't take an hour!!

 

[sgtboz]

Very interesting, gents. The reason the dribble is so small is because the oil level had probably dropped below the level of the seal. I'm not sure how long I'd operated it this way but I re-filled with 80/90w once I realized what had happened. It'd be nice if I broke in an just found a bit of debris in the way of the seal and that the bearings are still fine.

As I'm sure is the case for many of you, finding the time to make the fix is often much harder than just topping off the fluid and keep chugging on. I do enjoy tearing into things for the first time and see how it all works. Most things are mechanically logical once you see how it all fits together.

However, I do wish there was a vid on here to show the process. I don't have a WSM and I hate to spend the money on one before I sell the tractor.

Thanks again for the input.

Any concerns with using 80/140w oil as a possible band-aid in the meantime??

 

[D2Cat]

Sgtboz, your concern "It'd be nice if I broke in an just found a bit of debris in the way of the seal and that the bearings are still fine." about only the seal being bad is most likely.

I have an L305 that (when I got it) leaked so bad for so long the tire had decayed from the oil as the tractor had set for a few years. I took it apart and replaced seals. It's built pretty stout!

I'm sure you can find some threads on that kind of work here on the forum. It may not be the exact tractor, but not much difference.

And I'm slow because it took me more than one hour.

 

[hodge]

Have you searched youtube? There are videos on there dealing with seal replacement in different Kubota models.

 

[sgtboz]

That's really good to hear, D2. Thanks for the boost.

Hodge, you'd think in this day and age that'd be the first place a fella would check. I'll see what I can muster over there.

 

[rbargeron]

Alright, gents...where to begin? It's just a dribble but I know these things don't tend to heal themselves. I've seen lots of references to the commonality of axle leaks but no guide on what it looks like during the tear down. Do you happen to know of any? I've replaced lots of seals on brush hogs and other implements, but nothing along these lines. Any general tips or advice before I start unbolting things and making a mess?

Wouldn't you know this happened right before I planned to sell the thing!?

There are several write-ups on fixing front axle seals including this one. The diagram posted with it no longer loads but a copy is attached below, along with some of the text. It's a straight-ahead job - no surprises. FWIW using a heavier gear lube won't hurt but it won't help much either. High-viscosity oil still leaks out if there's an opening, just slower. Take care, Dick B

 

[sgtboz]

Excellent! Thank you so much, rbarge. That will help immensely.

 

[sgtboz]

Great idea! I never thought about using another WSM as a guide through kubotabooks.com. Like most have said, it's probably pretty obvious once you bust into the thing and see how it all goes together.

I really prefer to have the repair part available when I start the project. I don't have a good spot to keep a tractor that's in a tear down condition waiting for a part to show up.

Any idea which seal is most likely to be bad given the location of the drip?

 

[sgtboz]

There are several write-ups on fixing front axle seals including this one. The diagram posted with it no longer loads but a copy is attached below, along with some of the text. It's a straight-ahead job - no surprises. FWIW using a heavier gear lube won't hurt but it won't help much either. High-viscosity oil still leaks out if there's an opening, just slower. Take care, Dick B

rbarge, do you happen to have those other drawings you wrote about with regards to the "double-shear" discussion? I'm pretty fascinated by it all. If it's too much trouble to post...no worries.

 

[sgtboz]

I've gotten through the biggest part of my pond project where I needed the L3940. Now I need to get the supposed bad seal.

Can anyone please be so kind as to help give me just an ounce of extra confidence that based on where my leak is that I need the 050 seal listed on this parts drawing? I know for some of you that have been there done that there are often words of wisdom around "if you pull off that cap you'll bend it and need a new one so you better just go ahead and get it now."

Thanks so much, gents.

 

[D2Cat]

I think item #110 is also a seal. If I was in there all seals would get replaced.

 

[rbargeron]

rbarge, do you happen to have those other drawings you wrote about with regards to the "double-shear" discussion?......

Attached are the two pics from the 2008 post showing the axles used in the early USA models - note there were bearings above and below the axle center to support the kingpin/wheel assembly.

In the smaller '90s models the upper bearing was eliminated. Unfortunately leakage became a common issue. Kub redesigned a replacement seal but the issue has persisted. On many of today's newest models the bearing above has been reinstated, making old engineer coots like me smile.

Take care, Dick B

 

[sgtboz]

I was kind of afraid that might be the best advice!

Looks like 110 is officially a "plug" but I guess the idea is the same...once you're in there take care of what needs to be taken care of.

 

[sgtboz]

Attached are the two pics from the 2008 post that show the style of axle support that were used in the '80s - note there were bearings above and below the axle center to support the kingpin/wheel assembly.

By the mid '90s models the upper bearing had been eliminated. Unfortunately leakage became a common issue. Kub redesigned a replacement seal but the issue has persisted. On many of today's newest models the bearing above has been reinstated, making old engineer coots like me smile.

Take care, Dick B

Thanks so much for the pics, Mr. B. That's extremely helpful and I can see all the structural support that was there in the past. Quite a big change they made, it seems.

 

[sgtboz]

Well, the deed has been did. Most of the project went great EXCEPT FOR TWO SNAP RINGS that made me want to lose my religion (I didn't, in case you were wonderin'...HA!). My crappy little snap ring pliers have since been retired and the next day I bought a new set off Amazon.

For posterity, I'll put these pics on here in case some future guy or gal is searching and looking for information. I'm reasonably mechanically inclined but still have a hard time getting started on a tear down I've never done before. Maybe this pics will help someone else. The more frustrated I got, the fewer pictures I took!

 

[sgtboz]

A few more just for reference. I was fortunate that nothing was in a serious bind. I had to beat on the old seal pretty well to get it out but other than those ornery snap rings, it was pretty straightforward.

 

[mvwood]

sgt great pics!! I just did the same repair on my B26 TLB very similar except mine doesn't have a Cap on the bottom. I needed to separate the case to access the circ clip and then was able to tap the housing loose and expose the seal. My seal didn't come loose as nicely as yours though. I never really did any such work on my tractor before but I got a quote of $450 from my dealer to do this So I said I gotta learn this stuff somehow. I say all in all it took me a bit over a hour and $60 for parts. The bulk of my time was into cleaning the old sealant off of the mating surfaces so I could apply the new sealant.

 

[D2Cat]

I have an admiration for folks who can dis-assemble parts and get it all back together while taking pictures of the process! I sometimes think of doing it, but my hands are too dirty...and when I finally get inspired, I don't get the camera focused.

Pictures are a great aid to those who learn by seeing the process, and a confidence builder to the wary.

Post like this helps folks who come here whether it's tomorrow or next year. Good job.