b3030 front axle oil leak

[amolaver]

my b3030 has developed a pretty significant oil leak at the steering pivot (see attached pictures) .

is there a how-to for replacing whatever seal has failed? some searching indicates this is a pretty common problem, but i didn't find any step-by-step instructions. local dealer quoted me $500 and from the threads i've seen, it doesn't seem like this is a particularly big job. i also discovered - and wonder if it is related - that the tie rod end on the leaking side is also bad (the ball joint is trashed, lots of slop), so i need that part number as well. appreciate any assistance!

ahm

 

[CHDinCT]

You would need to buy a copy of the service manual for your tractor from your dealer or on-line. e.g. Messicks. I think they run $70-$80. It will have step-by-step instructions for all types of repair procedures.

 

[amolaver]

EDIT: Please read the thread for @DaveD1944 post re: my mistake on not removing the seal's inner race on the bevel gear case. This mistake is why i had to use the press / so much force for reassembly. Those statements are WRONG; you do NOT need a press for this job..

just to circle back on this, i was able to replace the leaking seal and figured i'd document some of it. apologies for the few pictures, but this should be helpful for anyone wishing to do this job on their own..

first, a caveat; based on my experience, i think you'll need a hydraulic press (20ton or greater) to be able to do this job. getting it apart took nothing more complicated than a ratchet, a few sockets, dead blow hammer, and circlip pliers (a single, external circlip - more on this later). you'll also need a clean place to work, a drain pan, and jack stands.

outline of the procedure:

a) raise front tires off the ground with bucket or jack and lower/secure with jack stands
b) remove wheel of affected side
c) remove cotter pin and castle nut, pop tie rod end out of 'front gear case'
d) drain axle lube (there is a drain on each - left/right - of the 'front gear case') - do yourself a favor and drain both sides, otherwise an unexpected pivot of the axle can shower you in SUDT/gear oil
e) remove 'axle flange' (poorly named - it's really the outer half of the 'front gear case') and release the external circlip holding the 'bevel gear case' to the 'front gear case'
f) separate 'front gear case' from the 'bevel' gear case' - this is where the seal that needs to be replaced lives.
g) remove 'bevel gear case' from tractor/axle
h) remove bad seal, press in new one
i) as they say..reassembly is the reverse...almost

i'm going to assume that a-d is self explanatory. lessons learned from the other steps:

e) the two halves of the front gear case - in kubota-speak, the 'front gear case' (inner half) and the 'axle flange' (outer half) are secured with 10 bolts and a liquid gasket. once the bolts are out, the only way for me to separate the two halves was carefully and methodically 'walk' around the seam with a cold chisel and lightly tap. eventually, i got a visible gap, and from that point was able to get the 'axle flange' separated within a minute. patience is key here - you do NOT want to damage the sealing surface of the two pieces. there is a large ball bearing attached to the 'axle flange' that seats in the 'front gear case'. because of this, DO NOT try to lever one side of the case to separate it; the 'axle flange' must pull straight out from the 'front gear case'

e2) the circlip is the elephant in the room. getting it off isn't too difficult, although it may help to put a jack under the 'front gear case' and apply some light pressure upwards. this will take any load off of it. the circlip sits above the small gear at the bottom of the 'front gear case'. putting the circlip back in place...well, that's when the press comes into play.

f) once the circlip is removed, the only thing holding the 'front gear case' to the 'bevel gear case' is friction between those two parts and the bad seal. now you get to release some frustration. on the top of the 'front gear case' is a cast boss (between the two cast steering stop bosses). plop a scrap ~6" long 2x4 on it, and beat the bejesus out of it with a dead blow hammer. i'd recommend you keep the jack under the 'front gear case' but with ~1" of space between the jack and bottom of the case. when the two parts separate, you don't want the 'front gear case' crashing to the concrete.

g) 4 bolts hold the bevel gear case to the axle tube. remove them, and using a dead blow hammer, GENTLY tap the cylindrical portion of the bevel gear case (roughly vertical) to separate it. there is an o-ring that provides the seal between these two pieces and as long as you're gentle, you won't have to replace it.

h) once the 'front gear case' and 'bevel gear case' are separated, removing the seal from the 'front gear case' also was a bit of a challenge. i tried all sorts of picks, seal pullers, etc. in the end, i took a 3/8" cold chisel and tapped around the external perimeter of the seal (where it was bound to the 'front gear case'). only a couple light blows got the stiction broken, and from there i was able to pull it out with a seal puller. again - DO NOT DAMAGE THE MACHINED SURFACE THE SEAL SITS IN. this is no little rubber seal - it is steel encapsulated in rubber, and is seriously tough.

h2) i drove in the new seal (P/N 32721-56223) with a 50mm impact socket and a dead blow hammer; improvise as needed. the thick walls of a 3/4 drive 50mm impact socket made a great seal driver

so...we've got three main parts off the tractor (ignoring the wheel/tire); the bevel gear case, front gear case, and axle flange. set aside the axle flange. i initially tried to re-attach the front gear case to the bevel gear case with the BGC still installed on the tractor. i eventually realized this is not possible. the two pieces need to be pressed together with enough force such that the circlip groove on the bottom of the vertical cylindrical portion of the bevel gear case clears the bearing in the front gear case (just above the small gear). thankfully, these parts are well engineered. on the bottom of the front gear case and on the top of the bevel gear case are flat bosses that are in the correct plane to apply force via a hydraulic press, seating the two pieces together and moving the circlip groove 'low' enough to put it back in place. my press (HF 20ton cheapie) doesn't have a guage, so i can't tell how much force i used...but it was quite a bit. i don't see any way to do this job otherwise. i couldn't even get the two pieces to really seat in the seal before putting it in the press - about 3/8" gap remained despite lifting the tractor via a jack on the FGC lower boss (ie, all of the tractor's front end weight was resting on that seal, and it still wouldn't even seat, never mind go deep enough for the circlip groove to be visible). Once pressed together, i was able to install the circlip (while still under pressure in the press).

now that the FGC and BGC are one unit, re-attach them to the tractor. NO liquid sealant is necessary for the BGC / front axle; the o-ring handles the oil sealing duties. once complete, COMPLETELY CLEAN/REMOVE any of the old liquid gasket from both the FGC and axle flange. the surface must be CLEAN; once i had scraped and brass brushed mine, i wiped it down with brake cleaner. lay a THIN bead of sealing compound (i used a hi-temp silicone because i had it laying around) on the axle flange sealing surface, and bolt it in place (note the two dowels to locate/clock it). i left mine to cure for 24 hours before refilling with gear oil, reattaching the tie rod end (well, i replaced mine - my shield got bent and tore the BJ boot), and remounting the wheel/tire.

was out and about cutting the grass and bushhogging for about 5 hours today and all seems well. no leaks, no bad noises

ahm

 

[Baby Grand]

Nice write-up! Thanks for posting.
Hope I never need it, but now I know it's here if I ever do.

 

[BeezFun]

Kubota should hire you to write the manual.
One thing I've done with tough seals like that one is screw a bunch of sheet metal screws into the metal portion of the seal, then use a small prybar to pull on the screw heads and pull it out.

 

[amolaver]

Thanks folks. Really not a bad job, but if I didn't have a press, I guess I would have brought the whole BGC/FGC/axle flange assembly to the dealer and let them deal with it. Of course, for less than half the cost of the labor for them to do it, you could own the hf press and do it yourself

Love the idea to put screws into the seal - will pocket that one thanks!

Hope this helps someone - one small nickel I can put in the bucket to thank all the other posters for the things I've learned over the years.

ahm

 

[DaveD1944]

Perhaps this thread is too old to reply to, but hopefully my update will be seen. I just replaced the same seal PN 32721-56223 on my B1700 front axle steering swivel and have some important notes about the reported problem where amolaver had to use a 20 ton press to get it all together.

First, when I attempted to order the seal online I was directed to call the vendor because there was an update involved related to the tractor serial number, so I ordered the seal via telephone, and this is the part that the parts person said (and continues to say) is the right seal, the same PN as above and as in the vendor's parts illustration (with the addition of the -620 suffix, which I am told is a manufacturer code appearing on all Kubota parts).

I examined it and found that it does not have seal wipes in the inside diameter as did the old one; rather, the ID is a solid metal tube coated with rubber, like the OD, and the ID was smaller, at 2.437", than the OD of my metal seal boss on the bevel gear case, at 2.568" (I still tend to measure in inches instead of mms). I noticed that this inner metal tube has an OD that was sticking out slightly enabling me to measure it, and this was the same OD as my bevel gear case seal boss OD. That led me to the conclusion that this seal had an inner race that was to be pressed onto a smaller diameter bevel gear case boss. So I pushed on this inner ring and it popped out, leaving me with a seal that is identical to the one I removed in looks and in OD and ID. It slipped snugly onto the seal boss, just like a seal of proper dimensions would.

I didn't have time to wait on a resolution to this problem with the vendor, so I went ahead and used the seal without the inner ring. Once I pressed it into the gear case, I was able to easily work the gear case with seal installed all the way onto the bevel gear case by lowering the front axle with gear case onto a wooden block. No hydraulic press was required. I put it all back together and it is working fine with no leaks.

So I strongly suspect that amolaver's problem was using the same seal I received without removing the inner ring on a seal boss of a larger diameter, and his 20 tons of force compressed the inner ring down against the upper bevel gear case bearing, moving it out of the way.

A couple other items: I used some heavy grease to keep the thrust collar up against the bevel gear case while I reinstalled the circular clip below it. And yes, before you even try this get yourself a heavy duty ring tool. Mine was too small to open the ring up enough to fit over the OD of the case and I had to fiddle with it to get it on. Also, when putting the bevel gear back, the end bearing loosened and the two collars fell out and I had to take the bevel gear case off again. I solved this by locktiting the inner bearing on, which held the bevel gear in place on the wheel attach shaft.

The vendor is looking into this problem and I will bug him until he comes up with an answer, which I will update here. In the meantime, posting this work-around here will hopefully help someone else with the same problem.
-----------------------------------------------------------------------------------------------------

Update: The vendor got back to me with information from Kubota. They have been receiving reports of difficulties getting the new seal on because of a difference in apparent OD of the seal wipe surface (as in my experience). It turns out that the reason is because the original seal was structured like the one I received and the inner ring stayed on the wipe surface boss at the top of the bevel gear case when the gear case was removed. That was likely the case with me and with amolaver. I had examined the area pretty thoroughly and did not see evidence of a ring, which should have included some evidence of the rubberized portion of it. But this was probably my problem and removing the new inner ring from the seal did no harm, as the original surface was not very worn.

Here are some photos. Kubota seals.jpg:Old seal on left, top up. New seal with inner ring intact on right. Notice that there is a flap, or flare, on the bottom side of the new seal. New seal with inner ring removed in middle, inner ring with red arrow pointing to seal lip wiping surface, same OD as my wiping surface on the bevel gear case, which in my situation may or may not be the older inner seal ring that I did not remove. Vendor's customer support checked with service and told me that the new seal has to be installed with flap down (towards the bearing), but why have the flap entirely within the seal bore where it can't do any good, plus the service manual page clearly shows the seal installed with the tension spring (tiny round thing in Kubota service page001) down, as in the original seal and and the new with the flap up (you can see the spring in the seals photo).

Bevel gear collars.jpg shows the two collars, #110, which fall right out when the inner bearing, #100, is loose on the axle shaft, #70, and allowed to move away from the case. Fixed by loctiting the bearing on the shaft, very lightly in case I ever have to remove it.

Finally, kubota thrust washer with arrow pointing to it. I smeared heavy grease on the top side and it stayed put throughout my shenanigans getting the retainer ring on.

 

[moship]

Thanks for posting your findings.

A few pictures to support your write-up would make it super deluxe!

 

[jonsstihl]

I had the same problem when I did the king pin seals on my B7800. I was using a 2lb dead blow hammer to try to get the parts together. I even tried using the tractors weight to seat the spindle but that didn't work.

I broke down and took it to the dealer. The mechanic but it on the bench and got out what looked like a 10 Lb dead blow hammer. and smacked it once and put the snap ring on. they didn't even charge me for it.

got home and bought a 5 lb dead blow hammer from amazon.

 

[amolaver]

DaveD1944 - thanks for the info. I'm not sure I understand completely (it's been a while since I had it apart ) but if I follow at all, it sounds like when I removed the old seal, the inner ring of the seal got left behind and squeezing it with the press just crushed it. I find that totally plausible.. The level of force with the press did seem higher than what I would expect, so this makes sense. I know I looked to see if anything was left behind and didn't note anything..but it is certainly possible I missed it.

If I have to take it apart again - the seal seems somewhat vulnerable if you're using the loader with loose material (sand/dirt). I used the B3030 to distribute and level over 100 yards of asphalt millings last fall and one of those seals has started to 'sweat' a little (nowhere near as bad it was before)..but it is only a matter of time..It will be interesting to see what I find. I imagine a massively crushed piece will be buried in there..

Thank you for taking the time to provide the info!

ahm