Front axle/differential leak

[michmike]

I recently found a leak dripping from under the king pin portion of the front end assy on my 1990 B 9200 HST 4 wd tractor. From the looks of it it has leaked out most of the gear lube from the differential. I have a service manual showing the breakdown of the assy, but I cannot see anything that might have caused this without tearing it down first, and the manual does not show a picture so I can determine ahead of time what I have to take apart. I told a friend about this and he said sometimes when you pick up a load thats too heavy with your fel, it sometimes causes these issues. But since as far as I can see the front axle assy is a sealed unit, at least sealed from the hydro's, so lifting an 'almost too heavy' load with the fel should have no bearing on the front axle assy.

I'm sure someone here has had a like or similar issue so I'm asking for some guidance on this repair. Thanks!

 

[GBJeffOH]

Clean it. Then watch for where the oil is coming out. It is pretty easy to take apart.

 

[GeoHorn]

What are you calling the “king pin”?
I see a possibility or two for leaks at seams/joints. Also possible you’ve cracked the case?

 

[michmike]

Geohorn, its not leaking at the cover or the main body. The leak is at the left front wheel from the point right under where, what the diagram in my manual calls the king pin. But, the picture in the manual is not the exact same as on the tractor. Its almost like a trunion cap of something, facing downward, where the lube ran out of. I'll try and go out and get a pic of it if I can manage.

 

[michmike]

Ok, lets try this.....

 

[michmike]

You can see where the lube came out of. My manual, although a bit different, does not show a closeup other than showing what appears to be a king pin assy. Imho, this looks like a 2wd front, not like my 4wd front.

 

[RCW]

Mike - - your manual's picture sure does look like a 2WD axle.

Try here for a parts diagram. Check the front axle section.

Kubota Tractor Corporation - Illustrated Parts List

- K-PAD - Parts Lists - Illustrated Parts Lists - diagrams

apps.kubotausa.com

 

[michmike]

Mike - - your manual's picture sure does look like a 2WD axle.

Try here for a parts diagram. Check the front axle section.

Kubota Tractor Corporation - Illustrated Parts List

- K-PAD - Parts Lists - Illustrated Parts Lists - diagrams

apps.kubotausa.com

Its only showing diagrams for the transmission.

 

[RCW]

Its only showing diagrams for the transmission.

Try the other tabs on left side of screen. Expand Front Axle/Wheel. This is the Front axle case. Think bevel gear case might help too.

I haven't had one of these apart, but quite a few guys here have, and have documented them on OTT. Varies by model I'm sure, but might also help.

I tried to find a B9200HST 4WD WSM (workshop manual), but didn't come up with one in my quick search.

 

[GreensvilleJay]

looks familiar....
odds are some 'grit' has got in between the oil seal and the vertical shaft.
My BX23s did the same... ordered new oil seal and gasket,needed really STRONG mid sized snapring pliers to get 'stuff' apart....I 'rolled the dice', cleaned up the parts(NO scoring),reassembled..hasn't leaked since (probably cause spares are on the shelf ).2 years now....
Not a difficult job IF you have the right tools and prints of 'how it fit' , nearby !!!

 

[mcmxi]

Take this for what it's worth, but the local dealer puts gear oil in the front axle rather than the optional UDT fluid. They claim that they see fewer leaks with gear oil. I haven't looked at the viscosity numbers for each, but that's what they told me when I did an oil change on the front axle of the BX25D a few years ago.

 

[michmike]

looks familiar....
odds are some 'grit' has got in between the oil seal and the vertical shaft.
My BX23s did the same... ordered new oil seal and gasket,needed really STRONG mid sized snapring pliers to get 'stuff' apart....I 'rolled the dice', cleaned up the parts(NO scoring),reassembled..hasn't leaked since (probably cause spares are on the shelf ).2 years now....
Not a difficult job IF you have the right tools and prints of 'how it fit' , nearby !!!

 

[michmike]

Right. Pretty sure I have the tools...years back was a certified mechanic....but it's the proper diagram portion I'm trying to secure. That and any type of hidden techniques or 'don't do's'..
..so I don't make a bad situation worse.

 

[michmike]

And now both fel cylinders are leaking....lol

 

[GeoHorn]

Ok, lets try this..... View attachment 96041

MichMike… I just did this repair on my M4700DT a couple months ago. It’s really not too difficult, even considering the first-time attempt that I screwed up. I’ll try to find a link to my post.

That’s called a “bevel gearcase” and that leak is due to a failed oil-seal which is replaceable with nothing more than hand-tools and a floor-jack. The only thing to worry about is to get ALL the old seal removed before trying to put it back together with the new seal. It’ll take you about 2 hours for the complete job once you have the new seal in-hand and ready to go.
You’ll also need 6-8 qts of gear oil to put into the front axle when finished. (It’s a great time to drain both front bevel gear-cases and do a complete oil-change on that axle. I used 80W90 gear oil.)

Here’s the link: https://www.orangetractortalks.com/forums/threads/front-axle-bevel-case-oil-seal-replacement.56731/

 

[Donystoy]

Common repair on these tractors especially if doing lots of loader work. Did both sides on my B7200. Replaced bearings, oil seal, tiny dust seal. and metal bushing that the oil seal rode on. Oil seals frequently leak from wear caused by movement from other worn parts.

 

[michmike]

MichMike… I just did this repair on my M4700DT a couple months ago. It’s really not too difficult, even considering the first-time attempt that I screwed up. I’ll try to find a link to my post.

That’s called a “bevel gearcase” and that leak is due to a failed oil-seal which is replaceable with nothing more than hand-tools and a floor-jack. The only thing to worry about is to get ALL the old seal removed before trying to put it back together with the new seal. It’ll take you about 2 hours for the complete job once you have the new seal in-hand and ready to go.
You’ll also need 6-8 qts of gear oil to put into the front axle when finished. (It’s a great time to drain both front bevel gear-cases and do a complete oil-change on that axle. I used 80W90 gear oil.)

Here’s the link: https://www.orangetractortalks.com/forums/threads/front-axle-bevel-case-oil-seal-replacement.56731/

Found these in my manual in the transmission section....lol. Is either showing the assy I need to address, and if so which seal are we talking about.

 

[GeoHorn]

MitchMike, putting the gearcase back together, I also used a bit of Permatex #2 at the seam to assure no seep at the case-split-line.

Looks like item 130 in the first pic and 110 in the second. (two different models? Pay attention to your serial number tractor when you look at parts catalogs/illustrations and when ordering parts.)

 

[Russell King]

@michmike
You may want to consider replacing the bearings and seals and o rings and all the gaskets (if any) when you tear into it. The parts are probably not too expensive. Bearing costs from the dealer may be high but you should be able to get the bearing from a reputable bearing supply house.

Good luck and take lots of pictures as you go through this so you don’t have trouble remembering how to reassemble it but since you have enough experience there is no reason you can’t do this yourself.

 

[michmike]

Try the other tabs on left side of screen. Expand Front Axle/Wheel. This is the Front axle case. Think bevel gear case might help too.

I haven't had one of these apart, but quite a few guys here have, and have documented them on OTT. Varies by model I'm sure, but might also help.

I tried to find a B9200HST 4WD WSM (workshop manual), but didn't come up with one in my quick search.

View attachment 96051

Ok, this fix is going to have to wait on my bad back acting up, so doing some prepping.....it's looking like I take out the 4 bottom bolts, remove the cap and the parts below the snap ring should come or drop right out....or so it looks.

And I figure to use the fel to lift the front to place a couple jackstands under the weight plate in front? My floorjacks sure won't reach....lol.
Been a while since I've wrenched on something I'm totally unfamiliar with, and the ol body isn't the best anymore.....so bending and squatting will be a test...