Front wheel differential lock stopped working one side

[aurellijus]

Good Morning! I have a ST401 and after replacing shaft seal in Bi speed mode turning left gridding noise appears turning opposite direction where the seal been replaced. I turned it off that then drives without a problem only noticed when had to engage full differential lock wheel not locking that side where seal was replaced.

What have I done wrong assembling it together?

 

[mikester]

Pretty unusual to see a SCUT/CUT with front differential lock are you sure you have one?

 

[aurellijus]

Pretty unusual to see a SCUT/CUT with front differential lock are you sure you have one?

Hi, yes I has Bi speed option to turn on and off.

Kubota tractor drive wheel-four improves feature ,tractors 4WD conventional On .steering speed same the at revolve wheels all front the turn a during so ,times all at .rear the than farther travel must wheels either ,drag wheels front the makes This turn a creating or turf the up tearing corrects Turn Speed-Bi .wide too s’that front the up speeding by deficiency this The .sharply turn you help to wheels resistance wheel front reduced is result with turns tight ,fast ,smooth ensure to .damage turf minimal TURNING SPEED-BI “Turn Speed-Bi ‘‘exclusive s’Kubota tractor drive wheel-four improves feature ,tractors WD4 conventional On .steering speed same the at revolve wheels all front the turn a during so ,times all at .rear the than farther travel must wheels either ,drag wheels front the makes This turn a creating or turf the up tearing corrects Turn Speed-Bi .wide too s’that front the up speeding by deficiency this The .sharply turn you help to wheels resistance wheel front reduced is result with turns tight ,fast ,smooth ensure to .damage turf m

 

[GreensvilleJay]

It seems to be a European model, can't find online parts pictures to see how front diff lock works.....

 

[SDT]

Hi, yes I has Bi speed option to turn on and off.

Kubota tractor drive wheel-four improves feature ,tractors 4WD conventional On .steering speed same the at revolve wheels all front the turn a during so ,times all at .rear the than farther travel must wheels either ,drag wheels front the makes This turn a creating or turf the up tearing corrects Turn Speed-Bi .wide too s’that front the up speeding by deficiency this The .sharply turn you help to wheels resistance wheel front reduced is result with turns tight ,fast ,smooth ensure to .damage turf minimal TURNING SPEED-BI “Turn Speed-Bi ‘‘exclusive s’Kubota tractor drive wheel-four improves feature ,tractors WD4 conventional On .steering speed same the at revolve wheels all front the turn a during so ,times all at .rear the than farther travel must wheels either ,drag wheels front the makes This turn a creating or turf the up tearing corrects Turn Speed-Bi .wide too s’that front the up speeding by deficiency this The .sharply turn you help to wheels resistance wheel front reduced is result with turns tight ,fast ,smooth ensure to .damage turf m

Not familiar with your model but my B1750 has Bi-Speed Turn, which is a two speed front axle designed to decrease both turning radius and turf damage when in FWA and Bi-Speed is engaged. It has no front differential lock.

 

[aurellijus]

It seems to be a European model, can't find online parts pictures to see how front diff lock works.....

I have manual print off if that would help to understand.

 

[GreensvilleJay]

hmm, posted pictures are the steering system not the 'diff lock'. That would be inside the front axle,where drive shaft goes in.

 

[SDT]

I have manual print off if that would help to understand.

Illustration appears to be a non-Bi-Speed Turn axle.

 

[North Idaho Wolfman]

Bi speed is not a locking Differential.
If anything it's the exact opposite as it allows one tire to spin faster than the other.

Now as to your problem.
If you have grinding, yes you have installed something wrong.

 

[aurellijus]

Bi speed is not a locking Differential.
If anything it's the exact opposite as it allows one tire to spin faster than the other.

Now as to your problem.
If you have grinding, yes you have installed something wrong.

Ok, thank you. Could not find any info online how differential lock works with Bi speed.

But is this the case that it works as it should. Regarding the gridding noise once Bi speed is engaged at turns any idea what can it be at at what too look at?

 

[North Idaho Wolfman]

We do not have the ST401 in the USA so no way for me to look it up.
You will need to visit or contact a local dealer to get the WSM / Service Manual, to find out to test and repair the bi speed case.

 

[aurellijus]

We do not have the ST401 in the USA so no way for me to look it up.
You will need to visit or contact a local dealer to get the WSM / Service Manual, to find out to test and repair the bi speed case.

Hi, managed to get WSM for my model. I am attaching front differential screenshots, hope they are the correct once.

 

[hagrid]

I'd wager the "two speed" portion is in the transmission case and the front axle is just a normal drive like we all have.

 

[SDT]

I'd wager the "two speed" portion is in the transmission case and the front axle is just a normal drive like we all have.

Not true.

Two speed mechanism along with torque limiting clutch is in front axle housing on right side. Mechanism is connected to steering linkage so as to shift Bi-Speed mechanism depending upon steering angle. Front axle assembly much different from tractors without Bi-Speed Turn.

 

[SDT]

Hi, managed to get WSM for my model. I am attaching front differential screenshots, hope they are the correct once.

Drawings shown are for non-Bi-Speed units.

 

[North Idaho Wolfman]

Hi, managed to get WSM for my model. I am attaching front differential screenshots, hope they are the correct once.

Those sheets are showing a NON Bi Speed front axle.
Let me do some digging and see if I can find a newer USA model of the same size that has Bi Speed.

 

[North Idaho Wolfman]

Here is a great video to explain bi speed operation.

 

[North Idaho Wolfman]

Ok after some research I've found that the front axle is not different.
And that a non bi speed an Bi speed have the same axle on newer models as the bi speed is done in the transmission on these.

So this brings us back to the original post, when you installed the seal, something got installed wrong.
or left out, or you have a bad bearing in the side that the seal was replaced.

lift booth front tires off the ground.
Have the tractor in 2wd, not running.
Turn the wheels by hand and listen for a noise.

 

[North Idaho Wolfman]

https://egcoles.com/wp-content/uploads/2021/06/PRINT_ST-Brochure_English.pdf

 

[aurellijus]

Not true.

Two speed mechanism along with torque limiting clutch is in front axle housing on right side. Mechanism is connected to steering linkage so as to shift Bi-Speed mechanism depending upon steering angle. Front axle assembly much different from tractors without Bi-Speed Turn.

ok, thank you. What that means for me. That it should lock front differential or not? left side well is spinning along with the rear once full lock applied. Also if Bi speed is turned on and turning left grinding noise appears for that moment.