BX-23 Front Drive Shaft Popping Out

[Happytule]

Hi, all-

I lost the u-joint for the front drive shaft on my BX-23.

I bought another one, installed it with the front drive shaft inserted, bolted the u-joint to the shaft coming from the back of the tractor, all good.

Except the front shaft, which does not have a hole for a bolt, keeps slipping out.

I suspect it was doing this with the old u-joint.

I've been using a box blade to scrape some very hard ground. Could that cause the tractor's frame to flex? That just doesn't seem likely to me.

Could the tractor's frame be bent?

What should I be looking at?

Thanks for any suggestions.

Chris

 

[Henro]

Are you saying the shaft is floating and not connected to either of the u-joints?

I lost the rear u-joint on my BX2200 last year. On mine the shaft is tied to the front u-joint with a roll pin. The rear u-joint ties to the transmission output shaft with a roll pin, and the shaft is free to slide in and out of the rear u-joint while being fixed in the front one.

My GUESS is that your set up should be the same as mine. Could the front roll pin be missing or broken?

 

[Happytule]

Are you saying the shaft is floating and not connected to either of the u-joints?

I lost the rear u-joint on my BX2200 last year. On mine the shaft is tied to the front u-joint with a roll pin. The rear u-joint ties to the transmission output shaft with a roll pin, and the shaft is free to slide in and out of the rear u-joint while being fixed in the front one.

My GUESS is that your set up should be the same as mine. Could the front roll pin be missing or broken?

Yes, the shaft coming from the front axle to the u-joint that is under the deck is free of the u-joint. This shaft does not have a hole for a roll pin.

Still, it doesn't seem like it should be sliding out of the u-joint unless something has become bent?

Unless scraping in the hard dirt, which is a pretty rough ride, is allowing the frame to flex?

 

[Henro]

I just looked at the parts diagram for a BX23S at Messicks and it shows a roll pin at the front U-Joint(on the shaft side) just like on my tractor.

Seems like you either have the wrong u-joint on your tractor, or perhaps the hole is filled with dirt or something?

Of course, I now see yours is a BX-23 and not a bx23S.

Suggest you look at a parts diagram and see if a roll pin is called for on your exact model. Does the front end of the driveshaft have a cross hole in it?

Screen shot of the BX23S parts list:

 

[Henro]

Just a follow up because your situation puzzles me.

Did you buy the tractor used?

I can not imagine the set up on my BX2200, which is the same tractor as a BX22 would be the same as the BX23S, and that the BX 23 would somehow be different.

Thinking back, I was able to install the u-joint at the transmission end that I lost, by simply sliding it down the splines on the drive shaft, and then onto the transmission output shaft. There was enough spline length to accommodate movement of the front axle, after the U-joint was attached to the transmission output shaft with the roll pin. I never saw the front Axel end of the drive shaft, as it was held in the front u-joint by the roll pin.

So at this point I am guessing you bought the tractor used, and someone may have replaced the front u-joint with a non-Kubota item. But I think after rereading your reply you said the front of the driveshaft does not have a cross hole to accept a roll pin. This does not add up, unless the drive shaft is also not a Kubota part.

As I said, I never saw the front of my drive shaft, but the parts diagram I posted the picture of seems to show short splines at the front end, which would make sense, if that end was pinned in place. Long splines would be needed at the back end that was designed to slip in and out.

Hope you come back with more details, or even better with a success story.

Edit: I think you also mentioned securing the replacement U-joint with a bolt? Only roll pins are used on mine, and only roll pins are used on the BX23S. This also seems strange...

 

[Happytule]

Just a follow up because your situation puzzles me.

Did you buy the tractor used?

I can not imagine the set up on my BX2200, which is the same tractor as a BX22 would be the same as the BX23S, and that the BX 23 would somehow be different.

Thinking back, I was able to install the u-joint at the transmission end that I lost, by simply sliding it down the splines on the drive shaft, and then onto the transmission output shaft. There was enough spline length to accommodate movement of the front axle, after the U-joint was attached to the transmission output shaft with the roll pin. I never saw the front Axel end of the drive shaft, as it was held in the front u-joint by the roll pin.

So at this point I am guessing you bought the tractor used, and someone may have replaced the front u-joint with a non-Kubota item. But I think after rereading your reply you said the front of the driveshaft does not have a cross hole to accept a roll pin. This does not add up, unless the drive shaft is also not a Kubota part.

As I said, I never saw the front of my drive shaft, but the parts diagram I posted the picture of seems to show short splines at the front end, which would make sense, if that end was pinned in place. Long splines would be needed at the back end that was designed to slip in and out.

Hope you come back with more details, or even better with a success story.

Edit: I think you also mentioned securing the replacement U-joint with a bolt? Only roll pins are used on mine, and only roll pins are used on the BX23S. This also seems strange...

Hi, Henro-

I bought the tractor new.

Looking at the diagram you linked, the part in question is labelled "030" and the end marked with an 'A' is the one that keeps unseating. Looking at the diagram, I don't see a pin on the end of the shaft (which seems a little strange to me, seems like it would be pinned.)

I crawled underneath and confirmed there is no hole for a pin an that end of the driveshaft. The splines on that end are at least two inches long, maybe longer.

I used a bolt to attach the new u-joint to the shaft going to the rear of the tractor because I'd read the rolled pins will sometimes work loose, so I got a SS bolt and a nylock nut.

I'm wondering if the u-joint could be too short. I ordered it from Coleman Equipment.

Unfortunately I didn't take a photo of the box it arrived in, which will make it difficult to confirm I received the correct part.

I wish I could get the dimensions on the stock u-joint. Better yet, I wish I could find the old u-joint, but I think it got tossed.

So what do you think? If the new u-joint was one inch too short it might be possible for it to pop out, I think.

Chris

PS- Are you in Mars, by any chance?

 

[whitetiger]

Are the snap rings (220) in place? If not, the shaft (90) can move rearward causing your problem.

 

[Henro]

Are the snap rings (220) in place? If not, the shaft (90) can move rearward causing your problem.

White tiger, your drawing is much better than the one I posted!

HT***8217;s issue seems to be the shaft is coming out of the front u-joint, which according to the drawing you posted should be held in place by a pin (not a roll pin but solid pin it looks like). I know for sure my drive shaft is pinned in place in the front but did not pay attention to what pins were used, and assumed they would be roll pins but may not be.

Anyway, if those clips you pointed to were missing, it seems like that should not affect the front end of the shaft, as it should be secured to the u-joint by the solid pin.

HT, you said the front was coming out, right?

HT, just to confirm, you are saying that the front end of the driveshaft does not have a cross hole in it, right? And obviously since you bought the tractor the parts were never replaced by anyone, so that possibility is eliminated.

Is your tractor model BX23 without any suffix added? (Or whatever you call a letter at the end)

Also, please confirm which u-joint you lost. Did the drive shaft also fall off with (or after) the u-joint? Just fishing for answers...

IF the shaft actually floats on your model WhiteTiger could have the answer. Finding the parts diagram for your EXACT model may offer the answer.

I have been to Mars PA many times but actually live fairly close to where I79 crosses the Ohio River.

Edit: After a reread, I see you are saying the end that is coming out is at the transmission end of the driveshaft...That is the u-joint that I lost, but later found on top of my mower deck after buying a new one from Coleman and installing it, so I have the original in hand and could measure the overall length if you think this will help.

So it looks like either WhiteTiger might very likely be correct, unless you got the wrong part without realizing it, which really could be the answer. If I get back to where I have that U-joint I will post a picture with a tape measure next to it, so you can compare roughly to what you have.

Did you have the shaft out of the front u-joint as some point? I guess so if you said there was no cross hole in it...

You might want to jack up the tractor and check to make sure there is not slop in the front axle, when pushed/pulled front to back at the ends. if there were this could be an issue that could also cause the same thing to happen. Perhaps there is slop in the front pivot.

 

[Happytule]

HT, just to confirm, you are saying that the front end of the driveshaft does not have a cross hole in it, right? And obviously since you bought the tractor the parts were never replaced by anyone, so that possibility is eliminated.

The rearmost end of the front driveshaft does not have a hole for a pin. The frontmost end of the front driveshaft must have a pin as the driveshaft has been bobbing around underneath the tractor and is still attached at the front (axle) end.

Is your tractor model BX23 without any suffix added? (Or whatever you call a letter at the end)

Just BX-23, according to the decals. I'll check tomorrow to see if I can find the mfg'ers sticker.

Also, please confirm which u-joint you lost. Did the drive shaft also fall off with (or after) the u-joint? Just fishing for answers...

This is the U-Joint that sits under the pedals on the right side and connects to the front axle and the driveshaft going to the back of the tractor. The front drive shaft is still firmly attached the front axle.

IF the shaft actually floats on your model WhiteTiger could have the answer. Finding the parts diagram for your EXACT model may offer the answer.

I have been to Mars PA many times but actually live fairly close to where I79 crosses the Ohio River.

I love going to Pittsburgh. My wife has 100+ cousins, most of them around Pittsburgh. It's so green there. And Iron City beer....

Edit: After a reread, I see you are saying the end that is coming out is at the transmission end of the driveshaft...That is the u-joint that I lost, but later found on top of my mower deck after buying a new one from Coleman and installing it, so I have the original in hand and could measure the overall length if you think this will help.

So it looks like either WhiteTiger might very likely be correct, unless you got the wrong part without realizing it, which really could be the answer. If I get back to where I have that U-joint I will post a picture with a tape measure next to it, so you can compare roughly to what you have.

Did you have the shaft out of the front u-joint as some point? I guess so if you said there was no cross hole in it...

You might want to jack up the tractor and check to make sure there is not slop in the front axle, when pushed/pulled front to back at the ends. if there were this could be an issue that could also cause the same thing to happen. Perhaps there is slop in the front pivot.

The axle being loose is a good thought. I'll take a look at it tomorrow.

I measured the U-Joint I got from Colemen Equipment.

3.5 inches is the overall length of the u-joint.

7/8 inch is the length of the collars on each end of the u-joint that the splines
slide into.

2.5 inches is the length of the splines on the drive shaft that keeps popping out.

Holding the driveshaft up to the U-joint, it looks like the driveshaft is barely fitting all the way into the 7/8 inch collar on the u-joint. It doesn't fill me with a lot of confidence.

I'm really thinking I don't have the right u-joint. Another inch in length would be a better fit, I think.

That's why I was hoping someone could measure their u-joint. Or why I was hoping I could find my old one. I guess I need to let that go.

 

[GreensvilleJay]

Having a BX23S , I'm curious about this....
So I have to ask WHAT is the difference between a BX23 and a BX23S ? I'm assuming they are made from the same 'bag of parts',with my S having the backhoe.
Looking at drawings and thinking 'mechanically', I have to say the rear U-joint HAS to be 'pinned' to the shaft coming from the tranny/HST/. If it's NOT pinned, it can move forward, down the splines of the front shaft and fall off the rear shaft.

 

[Henro]

I think we have the answer.

The original u-joint on my BX is 4.5 inches long. It is VERY likely yours should be the same.

If you look at the one you got from Coleman it probably has holes in it for cross pins at both ends. Just a guess but if it were the one for the front end it would use two cross pins.

I will try to attach a photo with this post.

Edit: This one cost me something like $85, and the front one listed for about half that. You said you do not have the box or paperwork anymore, but if you look at what you paid, and it is on the cheaper side, you may have inadvertently bought the wrong one. If they shipped the wrong one, not sure what then.

 

[Henro]

Having a BX23S , I'm curious about this....
So I have to ask WHAT is the difference between a BX23 and a BX23S ? I'm assuming they are made from the same 'bag of parts',with my S having the backhoe.
Looking at drawings and thinking 'mechanically', I have to say the rear U-joint HAS to be 'pinned' to the shaft coming from the tranny/HST/. If it's NOT pinned, it can move forward, down the splines of the front shaft and fall off the rear shaft.

You are correct. That is the way it is. There was some confusion in the beginning of this thread as to what was actually happening I think.

Not sure about the subtle differences in BX models with minor designation variations. Hopefully someone can enlighten us.

 

[whitetiger]

A BX23S =BX 80 series
A BX24D = BX 70 series
A BX23D = not sure
A BX25 = not sure
A BX25DLB = not sure
A BX25DLB-1 = not sure

I think i know what series they aline with but am not positive.

 

[whitetiger]

Having a BX23S , I'm curious about this....
So I have to ask WHAT is the difference between a BX23 and a BX23S ? I'm assuming they are made from the same 'bag of parts',with my S having the backhoe.
Looking at drawings and thinking 'mechanically', I have to say the rear U-joint HAS to be 'pinned' to the shaft coming from the tranny/HST/. If it's NOT pinned, it can move forward, down the splines of the front shaft and fall off the rear shaft.

Your BX23S is built on a BX 80 series tractor with all BX23S including a loader and backhoe. A BX23D is a several years older model with numerous differences.
It creates a lots of confusion when people only post part of their model number.
For example, there is no BX23 model, they are either a BX23D or BX23S which are substantially different from each other.

 

[Happytule]

If it's NOT pinned, it can move forward, down the splines of the front shaft and fall off the rear shaft.

That is exactly what is happening. That end of the driveshaft is not pinned, there is no hole in the drive shaft for a pin, which kind of makes sense as this would allow the shaft to slide in & out a little. That is why I'm thinking I may not have the right u-joint.

My tractor model is BX23-MLB.

 

[Henro]

Did you look at the picture I posted?

You will notice the u-joint off my BX, which is the one you are questioning, is 1 inch longer than what you have, and the end the drive shaft slides into is 1 inch longer than the end that goes on the transmission shaft.

You must have the wrong u-joint.

Case closed in my opinion.

Edit: I was in the same boat as you, but was lucky to get the correct part when I ordered it. Had the wrong part been sent, I would have installed it and likely ended up in the same situation as you have at some point. Only by chance did I find the u-joint on top of my mower deck, hidden in dried grass, when I cleaned it off before reinstalling it.

 

[GreensvilleJay]

I've looked at the parts picture in post #4 and it appears the 'upper' Ujoint is LONGER than the 'lower' Ujoint(front axle unit). THAT makes me think the upper Ujoint was replaced with the wrong part, probably a 'lower, shorter' Ujoint.
I'm still convinced , at least by that drawing, that the upper Ujoint MUST be pinned. As well 'mechanically' ,if it's left unpinned and 'floating' it can move fwd/bkd as well as slide up and down, something that shouldn't happen. I've never ,ever seen a 'floating' ujoint , and I'm almost 70 ( sigh).

BTW, I just checked that part number K2561-16820 and it's used on about 25 different Kubotas ! All the pictures I saw clearly show a pin used to attach the U-joint to the shaft.

 

[Henro]

I've looked at the parts picture in post #4 and it appears the 'upper' Ujoint is LONGER than the 'lower' Ujoint(front axle unit). THAT makes me think the upper Ujoint was replaced with the wrong part, probably a 'lower, shorter' Ujoint.
I'm still convinced , at least by that drawing, that the upper Ujoint MUST be pinned. As well 'mechanically' ,if it's left unpinned and 'floating' it can move fwd/bkd as well as slide up and down, something that shouldn't happen. I've never ,ever seen a 'floating' ujoint , and I'm almost 70 ( sigh).

BTW, I just checked that part number K2561-16820 and it's used on about 25 different Kubotas ! All the pictures I saw clearly show a pin used to attach the U-joint to the shaft.

I think (actually know) you are correct. As the OP said, the u-joint is connected to the transmission shaft with a pin, or in his case he used a bolt.

He also said later that the shaft never came out of the front u-joint, indicating it is pinned as shown in the parts drawings.

Almost 70? You could be my little brother!

 

[Happytule]

Did you look at the picture I posted?

You will notice the u-joint off my BX, which is the one you are questioning, is 1 inch longer than what you have, and the end the drive shaft slides into is 1 inch longer than the end that goes on the transmission shaft.

You must have the wrong u-joint.

Case closed in my opinion.

Oops, I did NOT see your picture when I posted my last reply. I think I missed the Page 2 button.

Thank you VERY much for measuring your U-Joint!

I was able to confirm today that Coleman Equipment sent me a U-Joint for the front end of the driveshaft.

Unfortunately, since I ordered the part on-line, using the part number they gave me, I am out of luck on getting a credit from Coleman.

Guess who WON'T be getting my business for the new U-Joint?

I'll be calling Messicks.

Thank you all for helping me figure this out. I've been fighting with this silly thing since November. Urk.

Oh, my Kubota is a BX-23D. It's odd that it's not marked that way anywhere on my tractor. I've made a note of the model number since I am sure I will forget it the next time I need it.

Oh, and if you look at the drawing Whitetiger provided, only one end of that U-Joint is pinned. FWIW.

So, thanks for the input, everyone. I say the case is closed & I'll be ordering my new U-Joint later today.

 

[D2Cat]

You say, "I was able to confirm today that Coleman Equipment sent me a U-Joint for the front end of the driveshaft.

Unfortunately, since I ordered the part on-line, using the part number they gave me, I am out of luck on getting a credit from Coleman.

Guess who WON'T be getting my business for the new U-Joint?"

If in fact, the parts guy chose the wrong part and sent it, I would call them and have a discussion about the discrepancy. Perhaps you will come out better then you think.

Now, if you did not give them the proper tractor ID data, the monkey is on your back!