BX24 Differential Lock........

[Shmudda]

I am new the the compact tractor scene and recently purchased a Kubota BX24. I have figured everything out with this thing so far, had to tinker and take the BH and FEL off along with the 54" MMM, just to see how hard they actually were to remove. Not to bad and I was surprised how easy they were to both remove and install.

Here's a question for other BX owners: When you have the machine in 4WD and the differential lock is engaged does it lock all (4) wheels together, or does it just lock the rear wheels in 2WD? It seems the lever located at the heel of your left foot will go all the way down sometimes and then other times it won't. This is about the only thing that has be perplexed right now. This is not the type of differential locks I'm used to, that's for sure! I have looked in the manual many times but just cannot seem to find the answer to this one.

I have yet to move any dirt or dig anything up yet with it as I basically took delivery on December 31 and then the snow and cold weather hit. It has been sitting inside since. I did build a Thumb for it as I see those can be a very useful accessory.

Boy the work I have planned for this machine!

Thanks in advance for any and all replies...........

Craig

 

[Singlecoil]

It locks the rear wheels only.
It will only engage at a certain point in the revolution of the axle, that's why it goes all the way some times and sometimes it doesn't. Push the lever down and hold pressure on it. At the right part in the revolution of the axle it will go all the way down, indicating that the rear dif is now locked. Keep your foot on it to keep the lock engaged.

 

[David Cockey]

Differential lock is on the rear differential only. Front differential remains open. When in 4wd the front and rear axles are always hooked together - no center differential. With the rear diff open at least one front tire has to be spinning for one or both rear tires to spin. With the rear diff locked then at least one front tire has to be spinning for the rear tires to spin together.

The differential lock works by sliding a pin or similar. For it to lock the parts in the differential have to line up. If they don't line up it won't lock. If one wheel is slowly spinning then the parts are moving relative to each other and after a little while they will line up and differential lock.

My proceedure for using the differential lock when a rear wheel is spinning.
1) Let up on the transmission pedal so it goes to center, neutral position.
2) Step on the diff lock lever. If it goes all the way down the diff is locked. If it goes down part way it isn't. In that case:
3) Step on the trans pedal until the tire just starts spinning while continuing to step on the diff lock lever. Within a few seconds the lever will go all the way down and the differential will be locked. Note that I just get the wheel spinning very slowly while waiting for the diff to lock. Don't step on the pedal hard so that the wheel spins quickly.

 

[David Cockey]

The differential lock works with or without the front axle engaged.

 

[Dataway]

Another question on BX diff locks.
The lock pedal on my BX2200 (500 hours, just bought it used) goes all the way down pretty much any time I want to use it, and it doesn't seem to lock the diff at all. Doesn't feel at like the diff lock on my NH 1715.

I'm guessing either diff lock shift fork is broken, or one of the pins in the linkage is either broken or missing. Although the pedal does return...haven't looked to see if the return spring is at the pedal or father down in the linkage.
Any thoughts.
JohnnyB

 

[KeithInSpace]

Mr. Dataway, you can test it on grass, dirt, or gravel. It will be pretty obvious if it is functioning properly while engaged. It is a pin that crosses the differential, so it is either LOCKED or open...not something in between.

If the diff lock was abused in the previous 500 hours, it would make sense that something could get messed up. Engaging it when the tires are spinning at greatly different rates (shocking loading the mechanism), on hard asphalt in a sharp turn (binding the mechanism), or some other 'mean' act could have bent/broken something.

Mine goes down without much trouble or drama and I can't speak to "feel" of your other machine. But I've found that it works as promised when working on a heaping pile of dirt or something...locks the two rear wheels together, plain and simple. No clicks, whizzes, or pops. When otherwise stuck in 2WD, either both tires spin or just one.

 

[Dataway]

The feel of the diff locks I'm used are the pedal stops midway...rear axle rotates, diff lock engages, pedals moves the rest of the way down.

The BX pedal just goes all the way down, at any time. I noticed it in wet grass going up a steep incline, right tire spinning, I stopped the tractor, pressed the diff lock, attempted to move forward, still the right tire spinning (slowly) left tire nothing, with the pedal all the way down. I'm very familiar with the typical diff lock on larger tractors, use them constantly. Pretty simple in operation....this lock appears not to do anything at all at the moment.

Checked the linkage, it rotates the diff lock shaft, linkage pin is in place. Then it enters the gearbox and I can't tell what's happening in there. On the other side of the shaft (inside the gearbox) there is another pin that engages the diff lock shift fork...I guess that could be broken.

Where is the return spring for the pedal. There doesn't appear to be one on the linkage, and I don't see one listed in the parts list in the diff lock section. The reason I ask is because if the spring is hooked up to the shift fork...and the pedal still returns, then that would lead me to believe the shift for is still pinned to the shaft properly at least.

I'm thinking someone stomped that pedal in a panic and broke the shift fork. Looks like a real pain to fix too.
JohnnyB

 

[offcamber]

I have a hard time engaging mine sometimes...I hold the pedal till it stops half way then keep holding until one wheel spins then it will go down all the way and engage both wheels'''Dataway yours does sound as if something has broken.

 

[Dataway]

Well found the return spring....it's right at the pedal pivot.

Ok....next, the service manual shows the diff lock shaft arm pointed down, the parts manual shows it pointed up. Which of course rotates the shaft in the opposite direction.

The shaft arm on my machine is pointed down, so the shaft is turned clockwise as the pedal is depressed. If the arm was pointed up it would turn the shaft CCW.

Can someone with a BX2200 take a look at theirs and tell me which way it should point (up or down). Just follow the linkage from the diff lock pedal back to the axle area, you'll see it attached to a small arm.

I also noted that the shaft on my machine moves out from the gearbox about 1/8" as the pedal is depressed.
JohnnyB

 

[ampsucker]

can't help you on the bx220 shaft, but i do have a tip for getting the diff lock to engage.

on my bx24, waiting until a wheel spins sometimes doesn't seem to work very well. if i'm mowing, it also tends to dig a wheel hole in the lawn. i found that if it's possible to know in advance when you'll need it, like for example mowing a wet part of the lawn, if you apply pressure to the lock lever and turn the front wheel left and right while moving, the diff lock will engage almost immediatley everytime.

i think rocking the steering is getting the spiders in the rear differential to spin back and forth relative to each other and that does the trick for getting the pin to slide home.

hope that helps somebody!

amp