What brings a hydrostatic trans back to neutral? F2100 mower

[the mean fish]

I have a Kubota F2100 front deck mower that I'm trying to bring back to life and even after reading the service manuals it came with I can't figure out what physically brings the hydrostatic trans back to the neutral position when you take your foot off the pedals? When I take my foot off of the forward or reverse pedal it does considerably slow down but it doesn't come to a complete stop, I have to use the pedal for the other direction to get it to stop which is pretty hairy when you're mowing around stuff in the yard. The trans seems to be working correctly and smoothly, it's just not coming to a stop when you let off the pedals which I assume it should do. I'm sure the F2100 shares a drive-train with something else but this is my only Kubota machine and I've never worked on anything else.

Anyone know what's supposed to bring it to a stop or back to neutral?

 

[Eric McCarthy]

Try the break pedal.

 

[helomech]

Sounds like it need lubrication. I think it is just a spring that does it.

 

[the mean fish]

Try the break pedal.

It's a 4x4 mower and it just overpowers the brakes. Are you saying there's a link somewhere between the brakes and the trans mechanisms?

 

[the mean fish]

Sounds like it need lubrication. I think it is just a spring that does it.

I think I see the spring, I just need to know what to lubricate. I've greased everything I can find and it's gotten a lot better but it's still not good enough to trust. Maybe it's just an adjustment that needs to be made to the neutral position...

 

[bruceatlam]

New spring?

 

[Eric McCarthy]

If you let off the hydro pedal the apply the break pedal. Alot of the time I've noticed with hydros, which is another reason I dont like them its all about timeing. As you approach the area you want to stop at plan ahead for it.

 

[the mean fish]

If you let off the hydro pedal the apply the break pedal. Alot of the time I've noticed with hydros, which is another reason I dont like them its all about timeing. As you approach the area you want to stop at plan ahead for it.

I've tried that and it's not working, I'm wondering if there a mechanical/physical connection between the braking pedals and the transmission control mechanism or does it just slow the tractor down using the brakes enough to stop the transmission?

 

[helomech]

I don't know about your particular tractor, but it sounds like a lubrication issue to me

 

[Eric McCarthy]

Could be time to replace the break pads on the mower then.

 

[the mean fish]

Could be time to replace the break pads on the mower then.

I just don't see how that would actually solve the problem, if the trans is still stuck "in gear" and I lock up the brakes that isn't going to affect the trans. I tried it yesterday at a very low RPM on the engine and it stalled the engine so it's not pulling it out of gear.

 

[kuboman]

Does it act the same in reverse? In other words if you are going ahead and let off it still keeps going ahead. Right?
If you are going in reverse does it continue in reverse or does it then start going ahead again?

 

[the mean fish]

Does it act the same in reverse? In other words if you are going ahead and let off it still keeps going ahead. Right?
If you are going in reverse does it continue in reverse or does it then start going ahead again?

Yes, exactly the same in reverse. It has a forward and reverse pedal right next to each other and they work opposite of each other obviously. When you want to stop you have to feather the other pedal until the tractor comes to a complete stop otherwise it'll just inch forward or backwards. When you let off it does drastically decrease in speed and almost come to a stop but not completely.

 

[kuboman]

Yes, exactly the same in reverse. It has a forward and reverse pedal right next to each other and they work opposite of each other obviously. When you want to stop you have to feather the other pedal until the tractor comes to a complete stop otherwise it'll just inch forward or backwards. When you let off it does drastically decrease in speed and almost come to a stop but not completely.

There is a centering dampener on the hydro mechanism and they do go bad regularly. I don't think it is an adjustment problem because that usually shows up as a forward or reverse problem not both. It may be just sticky linkages.

 

[the mean fish]

There is a centering dampener on the hydro mechanism and they do go bad regularly. I don't think it is an adjustment problem because that usually shows up as a forward or reverse problem not both. It may be just sticky linkages.

I noticed the dampener but when I asked my Kubota service guy about it he said all it did was stop you from going from forward to reverse too fast. I didn't realize it had any kind of centering properties in it but that would make sense. If I pull it off how can I tell if it's bad? Should it just act like a shock absorber or will it actually help center the mechanism?

 

[kuboman]

I noticed the dampener but when I asked my Kubota service guy about it he said all it did was stop you from going from forward to reverse too fast. I didn't realize it had any kind of centering properties in it but that would make sense. If I pull it off how can I tell if it's bad? Should it just act like a shock absorber or will it actually help center the mechanism?

Umm...now that you mention it the dealer might be right. But cannot remember if it has centering action or not. I do know I have replaced many because they seem to go bad after a while. The are the same on JD and every other hydro I have seen. Best to take it off and it should act like a shock. But I think it still would help to center things with just the action of it.
I have a used one kicking around somewhere and I will see how it works. It was weak but not toast so I changed it anyway.

 

[the mean fish]

Ok I've checked the dampener on my tractor and it doesn't seem to have much resistance whatsoever, I can't imagine it's doing anything at all. I'm going to order a replacement whether it fixes the issue or not, it looks like it's shot and worn out.

 

[cjwilson78154]

Ok I've checked the dampener on my tractor and it doesn't seem to have much resistance whatsoever, I can't imagine it's doing anything at all. I'm going to order a replacement whether it fixes the issue or not, it looks like it's shot and worn out.

Hey Mean Fish/OT, I know the thread is 13 years old but... If you're still around I'd love to know how you solved this. I have the same machine. Replaced the damper already. It still Doesn't stop going forward or backward when I let off either pedal. Gotta tap the opposite pedal a bit. I have greased linkages. I don't have a shop manual yet to see if there's any adjustment. Cheers!

 

[North Idaho Wolfman]

Hey Mean Fish/OT, I know the thread is 13 years old but... If you're still around I'd love to know how you solved this. I have the same machine. Replaced the damper already. It still Doesn't stop going forward or backward when I let off either pedal. Gotta tap the opposite pedal a bit. I have greased linkages. I don't have a shop manual yet to see if there's any adjustment. Cheers!

These are the parts that set and bring the HST back to neural.

 

[cjwilson78154]

Thanks Wolfman. I'll revisit the linkages and grease again! I see a couple of places that can allow adjusting on your diagram. Maybe over the holidays I can make time to see if they are reachable and adjustable. Cheers!