New Rear U Joints Needed-- Again

FTG-05

Active member
Well, it looks like it's my time in the bucket for my rear axle shafts!!!

Pics are below, one which is the way it *should* look and two pics showing how loose the right rear outer axle shaft is currently. Is this what happened to you guys?

I can tell that someone has already replaced something in the rear since both plastic boots are missing their steel rings.

And speaking of steel rings, why not just use SS hose clamps? Not enough room?

Thanks,

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FTG-05

Active member
Maybe this has been covered before, if so, just post the post number or whatever, but:

What holds the inner and outer axle shafts together? I have the Messick's detailed rear axle figure in front of me(D30100 Rear Axle) and for the life of me, I don't see any mechanism that keeps the outer from just running on out the end of the axle housing.

What am I missing? :wtf:
 

bordercollie

Gold Site Supporter
Gold Site Supporter
It looks like you will need bearings and seals too- from looking at your pictures below. Make sure your axles are not screwed up before you order the joints..... You can get those boot clamps at most auto parts stores and use a pair of pliers and a screwdriver to put them on. collie
 

bordercollie

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Also, have you already removed a cotter pin from those castle nuts yet? if not, they may have be put together without one .. that is bad.... if they have because the shafts can come loose - like it looks in the picture... collie

edit. the cotter pin should slide through a hole in the axle and the castle nut hips. Just get the hole lined up with the deep part of the nut.. allowing the cotter pin to be wedged through the castle hips of the nut and shaft and then spread out on the end .. to keep the nut from moving and the pin from coming out.. collie
 
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FTG-05

Active member
It looks like you will need bearings and seals too- from looking at your pictures below. Make sure your axles are not screwed up before you order the joints..... You can get those boot clamps at most auto parts stores and use a pair of pliers and a screwdriver to put them on. collie

Seals and bearings are already in the cart at Messick's, I'm just waiting to call them in the morning and make sure they will fit my model RTV 900.

I also plan to check the outer axle end to make sure it's not buggered up, but I think it's the inner bearing that bit the dust; I heard it go out a couple days ago, after that I noticed the wheel was cocked.

How can I tell if I need to change out the u-joints?

Thanks for your patience for those that have done this before and is now old hat!!!!
 

herman48

Active member
Well, I had to replace one of the rear H-Joints on this 1948 unit--a real clunker. Now I have to wait three months for the other one to be replaced, because the "mechanic" wants the left one to function perfectly before cutting into me again. Everything went well, but I must stay away from my Kubota for quite a while, or I could mess something up in my left H-Joint only by trying to hoist my carcass up into the driver's seat. I can't complain, though. I am grateful that the technology that I needed twice to reopen and keep open my coronary arteries already existed, and that H-Joint replacements are about as common and simple as appendectomies today...
 

Art454

Member
First thing wash the area before you even start the project....unless you love to play in the dirt......lol
 

Fitch

Active member
There is an outfit that sells complete axle shafts for about half the price Kubota charges. I can't find the link at the moment and have to go to the barn, but if they will work, they might be the solution depending on what you find.

Fitch
 

bordercollie

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To see if the ujoints need replacing, I'd jack both rear wheels off of the ground where they can freely rotate and then secure it so that it won't fall on you with stands etc.. . I use a floor jack under the center brace area and stay away, far away, from the transmission housing. Then rock the wheels and see if there is any slack or hesitation in the visible joints as you wiggle the tire back and forth lightly. You can see looseness in the visible joint that way....
If it were me, I would pull the bumper tube and check the whole thing. You will need to do that anyway to get at the joints. Take a lot, a whole lot ,of pictures as you do it so you can look back on it and remember how things came out.
If those castle nuts were not correctly tightened down in the first repair, then it could be &%^$#@ in there.. In that case you would need new axles and the ujoints would come preinstalled then add bearings and seals , and whatever else is worn or buggered up. You are not bothering us a bit. We are all learning and helping each other-- is a good way to help our spirits as well. You have a great evening and don't let it get you down.
edit .. I believe the link fitch is talking about is listed below.. They also have a good link on breaking down the rear.. but at that time didnot mention a sealant which you do need between the transmission and inner joint assembly collie
 
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FTG-05

Active member
I'm still having trouble understanding how the outer axle shafts stay in place *or* how they come out of the inner axle housing.

I looked at that superATV.pdf posted above. They hang the axle housing instead of taking it off. That sounds good since I really don't want to be working on this while the whole shebang is sitting on the floor - right now, my RTV is up on my shop lift at a very comfortable 6' above the floor; essentially right in front of my face.

Apparently, the outer axle shafts come out by swinging the housing to the side you want take apart. So that means you're compressing the other side axle shafts to get that clearance. Is there that much play or engagement between the inner and outer axle shafts?
 

pepr

Senior Member
SUPER Site Supporter
FTG-05, you are correct. The bumper assembly must be pushed to one side almost to the point of bottoming out the shaft assembly on the one side. At that point the opposite side shaft assembly will separate.

If the outer u-joint(s) must be replaced, the bumper assembly would have to be dropped to enable pressing or bumping the outer shaft out of the bumper assembly.

In my recent case of u-joint replacement, removal of the outer shafts resulted in the inner bearing and seal being removed with the shaft from the bumper assembly.

Again in my recent experience, the outer u-joints were in great shape while the inner u-joints were severely worn on the 2011 RTV 900 XT with only 800 hours of easy operation.

Philip
 

Fitch

Active member
The castellated nut holds the outer axel in place. The fact that it looks loose is one of the concerns.

Fitch
 

Mark.Sibole

Well-known member
with the outer looking like that it looks to me like he lost the bearings causing the slop.When you have all of the bearings in place and tighten up the castle nut that is what holds the outer shaft in place.with the inner housing being tapered when you add the inner and uter bearings and seals in the taper when you tighten up the nut it all snug up together .As for the inner axle and outer its on a slip shaft system.As your suspension goes up and down on either side the shafts slip in and out of each other to make it sort of an independent suspension system.When you remove the boot they will seperate.When you re assemble add some good grease in there to keep them slideing freely and re center the boot and you can use a good high quality sip tie like they use for hvac pipe to hold the boot in place and keep it air tight to keep the water and gunk out.
 

Fitch

Active member
I completely agree, it doesn't look good for the bearings and seals, but as Collie pointed out the cotter pins are missing which suggests someone has messed with it. The only thing I'm sure of is it needs a complete disassembly and assessment. From the pictures it appears there is a chance that one (or both) of the outer axle shafts is toast as well as the bearings and seals.

The good news is that it's all fixable. Parts are available.

Fitch
 

bordercollie

Gold Site Supporter
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I look at the inner and outer going together under that boot, much like a PTO shaft on a piece of tractor equipment. It slides and gives a bit. When you remove the clamps on that boot, If it were me, I'd push it aside and take notice of the phasing at that point and mark the way the splines are aligned under that boot , before the union was free completely. collie
 
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