B7510 Front End Whine

[NoJacketRequired]

Just acquired another B7510 - trying to standardize my fleet. (I know, I know - I dreamed for 35 years of owning a Kubota and now I own three of them, but one of them will soon go...)

This new tractor has a "whine" coming from the front wheel drive line. I jacked the front end up and turned the wheels by hand - the whine can be heard as the wheels are being rotated. There doesn't seem to be a difference in sound when the engine is driving them - so no change in sound from 2wd to 4wd.

I've checked the obvious - fluid level is good, looks clean, smells like UDT.

The paint has been knocked off the nuts on the right hand side where the horizontal axle transitions to the spindle. That area is also slightly wet with leaked oil, indicating it likely has been opened and not re-sealed properly. Other than that the machine is "factory new" underneath, even has the original factory hydraulic oil filter since it has less than 400 hours on it.

I'm open to suggestions as to potential causes, and $$ cost to fix. I'm busy these days so this likely will be a dealer repair...

 

[100 td]

I'm open to suggestions as to potential causes, and $$ cost to fix. I'm busy these days so this likely will be a dealer repair...

No point in getting guesses from us as we can't see inside it, take it to the dealer and get it quoted!

 

[NoJacketRequired]

Truth be told, I've had some excellent troubleshooting assistance provided via this site and have, to date, only gone to the dealer for parts. I appreciate having some idea what might be wrong before the dealer's quote makes my jaw hit the floor!

 

[100 td]

Truth be told, I've had some excellent troubleshooting assistance provided via this site and have, to date, only gone to the dealer for parts.

I understand totally, but the reason I said take it to the dealer is twofold.
You stated you are busy these days, and it would likely be a dealer repair, so I assume you aren't able to work on it yourself.

You have also said there is a whine, and that indications show the axle housing has been worked on previously and is leaking from a the previous repair.

Whilst there are some very experienced techs on this site, even they are going to be guessing big time on what has gone wrong previously, prior to someone else working on it, what that work entailed, and why there is a noise still in it after the previous repair, why it is leaking now, and what could have failed again, or additionally, WITHOUT YOU pulling it apart.
Get a price on a front axle assembly and anything cheaper is a bonus. YMMV.

 

[100 td]

And I really do hope others chime in and give you the answer you are looking for.

 

[Benza]

Truth be told, I've had some excellent troubleshooting assistance provided via this site and have, to date, only gone to the dealer for parts. I appreciate having some idea what might be wrong before the dealer's quote makes my jaw hit the floor!

Sounds like a bearing issue, honestly. Seeing oil means that a seal has gone bad. In my experience, bad seals typically result from a bearing failing, and metal getting to where it shouldn't be - Tearing up the oil seal.

You said the growl is coming from the front axle driveline; Is the noise centered right there, or on one side instead of the other?

 

[NoJacketRequired]

The sound appears to be centered, however I'm at a bit of a loss to be able to tell how close to the axle it might be... It could be coming from further aft in the propeller shaft, but I'm not sure.

As for the seal, in this case it would be the perimeter seal between the horizontal axel and the vertical spindle. Just a weep, and likely evidence the previous owner had taken that joint apart and not put a new gasket in place before reinstalling the bolts holding these two pieces together.

At the moment it's a bit moot since the machine is now sitting at the dealer.

Interesting note... a bone stock B7510 on R1 Ag tires fits perfectly in a U-Haul 4'x9' motorcycle trailer and tows like a dream!

 

[NoJacketRequired]

And now for the rest of the story...

Dealer called this afternoon. Whining noise has been fixed. I say "WHAAAAT?!?!"
Turns out the shield over the propeller shaft was slightly bent and had a ding in exactly the right spot to create a very nasty noise. The mechanic working on the issue agreed that it sounded like a bad bearing but couldn't diagnose the sound by ear and took the shield off to examine the prop shaft. Viola, the noise went away! He has now hammered it back to its proper shape and can't reproduce the noise.

Cheap solution, far cheaper than I had expected.

I also had them change the hydraulic oil, engine oil and filters since they already had their hands dirty. Total bill is less than $100 more than what I paid for the raw materials to do the hydraulic and engine oil/filter change on my other B7510 last year. And I didn't have to get my hands dirty. Good deal!

 

[sheepfarmer]

Eureka!