F3680 Wheel Spin

[Gary55]

Recently bought Kubota F3680 with rotary deck. When I make an turn end of each
stretch the front inside wheel spins, a lot. To help this I creep very slowly, make
an bigger turn and gentle on the pedal. The fuller the lock the more wheel spin.
Gearbox has recent oil change
Any help greatly appreciated
Thanks

 

[GreensvilleJay]

sounds like the 'differential lock' is ,um, well, locked....

 

[Gary55]

Thanks. Still spins, tried 2wd and 4wd. the inside wheel whilst in diff lock does spin slightly
more so than when not engaged. Without experience of an second machine I can't be sure
how much! I guess there would be some spin depending how much gas you give it! I use it
for mowing an games pitch so the grass isn't long. Thanks again

 

[SDT]

Thanks. Still spins, tried 2wd and 4wd. the inside wheel whilst in diff lock does spin slightly
more so than when not engaged. Without experience of an second machine I can't be sure
how much! I guess there would be some spin depending how much gas you give it! I use it
for mowing an games pitch so the grass isn't long. Thanks again

Would expect slippage of inside wheel when in FWD and/or diff lock engaged.

Would not expect such slippage when neither engaged and traveling at slow speed on level ground.

 

[Gary55]

I assume front and rear gearbox's are getting the required oil pressure to make them
work. There seems to be firm drive in rear wheels. I'll consider an engineer take it for
a spin. I use it basically once a week so not a lot. It's possible some wear inside maybe
responsible.

 

[t.essl]

Hello Gary55
Have you found a solution to your problem? My F3680 mower has the same issue.
Or does anyone else know a solution?
Best regards
Thomas

 

[PoTreeBoy]

Recently bought Kubota F3680 with rotary deck. When I make an turn end of each
stretch the front inside wheel spins, a lot. To help this I creep very slowly, make
an bigger turn and gentle on the pedal. The fuller the lock the more wheel spin.
Gearbox has recent oil change
Any help greatly appreciated
Thanks

I sometimes have that issue on the 2WD Ford when brush cutting, especially when I'm in a hurry and/or the ground is very dry. Adding front weights helped, but I drag a little steering brake on the side I'm steering toward for the best effect.

For your F3680, I would check:
1. Does your machine have steering brakes? Looking at the parts figures, I see 'Turn Assist Brake Kit', but I can't tell if it's standard or optional. If you have them, try dragging one a little as you turn.
2. Are the mower wheels free to rotate and swivel? If pneumatic, are they well inflated? Any resistance to side load will make it harder to turn.
3. Is the full weight on the mower wheels, not supported by the tractor? Any weight carried on the tractor reduces the weight on the rear steering wheels, causing less traction.
4. What's the condition of the rear tires? Worn tires will tend to skid more.
5. If nothing else helps, you might try adding weight to the very rear of the machine.

 

[North Idaho Wolfman]

I sometimes have that issue on the 2WD Ford when brush cutting, especially when I'm in a hurry and/or the ground is very dry. Adding front weights helped, but I drag a little steering brake on the side I'm steering toward for the best effect.

For your F3680, I would check:
1. Does your machine have steering brakes? Looking at the parts figures, I see 'Turn Assist Brake Kit', but I can't tell if it's standard or optional. If you have them, try dragging one a little as you turn.
2. Are the mower wheels free to rotate and swivel? If pneumatic, are they well inflated? Any resistance to side load will make it harder to turn.
3. Is the full weight on the mower wheels, not supported by the tractor? Any weight carried on the tractor reduces the weight on the rear steering wheels, causing less traction.
4. What's the condition of the rear tires? Worn tires will tend to skid more.
5. If nothing else helps, you might try adding weight to the very rear of the machine.

1: No they do not have steering brakes
2: Possible?
3: He has the front wheel spinning not the steering wheel spinning.
4: Rear tires are not the issue
5: Adding weight to the rear of the unit will make the problem worse not better.

This is what he's dealing with.

Sounds like he just needs to lean into the turns to keep the front wheel in contact with the ground.

 

[t.essl]

Thanks for you answers.

I'm not driving fast enough to have to lean inwards.

To be clear:
On concrete, it works as it should. The inner wheel turns slowly.

On grass, even dry grass, the problem persists. The inner wheel spins freely. It turns as fast as the outer wheel.

Since it works on concrete, I don't think the differential lock is stuck. The pedal mechanism also works.

The weight distribution should be correct, and the wheels of the mower deck spin freely.


Great forum by the way

 

[Russell King]

From what you are saying I would be suspicious of the differential lock mechanism. To me that is the only thing that “locks” the rear wheels together (assuming that is not an independent drive wheel machine, I think it is just a tractor that is “backwards”).

They often get abused by an operator and shear the lock pin into the axle gear. I (with a stretch of imagination) imagine it could still lock enough to spin on grass but not enough for concrete. Is there any popping or grinding noises on concrete when turning?

Here is the illustrated parts list and #60 may be stuck?

 

[SDT]

Thanks. Still spins, tried 2wd and 4wd. the inside wheel whilst in diff lock does spin slightly
more so than when not engaged. Without experience of an second machine I can't be sure
how much! I guess there would be some spin depending how much gas you give it! I use it
for mowing an games pitch so the grass isn't long. Thanks again

Expect weight transfer is unloading inside wheel allowiing slippage.

Wheel weights might help.