The PTO does not stop Kubota M5112

[Ionut002]

Good evening everyone, I'm new to this forum, and I don't speak English very well, but I'm back with the following problem with a 2021 Kubota M5112 tractor.
When I start the tractor, the PTO rotates without the PTO button being pressed.
It still spins with a not very high rotation, but it still has enough power.
I don't think the button is to blame, because I also disconnected the button plug, and then the plug from the distributor for the PTO that leads to the solenoids, of course when I disconnected it, I got some error codes for the PTO as well as for the 4x4.
But the PTO kept spinning.
The tractor was bought recently, I thought it was a problem either with the button or because it doesn't have enough oil for the transmission,
There would also be the problem that the previous owner never changed the oil in the transmission during the 1400 hours, being a very black oil, an oil almost as black as the one in the engine.
When I changed the oil and opened the filters, there was a lot of metal filings on the magnets.
Could that filing have damaged the PTO solenoid and stopped working properly, allowing a certain amount of oil pressure to escape to the PTO clutch?
It should be mentioned that if I stop the tractor, I can turn the PTO shaft by hand, not very easy but not very hard.
So I don't think the clutches are damaged or deformed.
I would also try to move the location of the solenoids, to put the solenoid for the 4x4 in place of the one for the PTO to see if the solenoid is somehow to blame and the oil pressure drops.
Another thing to say is that if I engage the PTO from the button, the light for the PTO lights up on the dashboard, and the revolutions increase at the PTO depending on how much I accelerate, so it would mean that somehow the solenoid is working.
But maybe it has the filing in it and when it should stay closed it doesn't stay closed enough and let the pressure pass.
Has anyone encountered this before?
Can someone help me with some advice?

 

[GrizBota]

Your trouble shooting skills as well as your writing skills seem spot on to me. Will the PTO stop turning when it is off and there’s an implement hooked up to it (providing a bit of drag to it rotating)? If so, based on what you’ve described, I’d probably use it and see how it goes.

 

[Ionut002]

It offers quite a lot of resistance, and you can't stop it by hand, I could only slow it down when I forced it with a piece of wood.
It is as if it is half connected, even if it is turned off from the button

 

[GrizBota]

So if there was an implement on it, would it turn it even with the PTO in the off position? If so, indeed that’s a concerning problem.

I presume you changed the hydrostatic fluid? Did you use Super UDT2?

 

[Ionut002]

Yes, I changed the hydraulic fluid, and new filters, I did the complete overhaul

 

[North Idaho Wolfman]

We don't have a M5112 in the USA, But this is a M5111, so guess would be it very similar.

Finding metal in the system and the clutch not stopping rotation means it's probably torn up the clutch, and the clutch brake (in yellow).

It would require splitting the tractor to get to the clutch and repair it.

 

[Ionut002]

I would really hope that this is not the case.
In fact, the tractor was used a lot for PTO.
But I think that it should not fail after 1400 hours of operation.

 

[North Idaho Wolfman]

I would really hope that this is not the case.
In fact, the tractor was used a lot for PTO.
But I think that it should not fail after 1400 hours of operation.

It really can't be anything else.
The PTO brakes usually fail because of ON / OFF cycles under a heavy load.

 

[Botamon]

Does it still do this after the tractor has been worked and everything (especially the hydraulic fluid) is hot? I have an older tractor that spins the PTO shaft until it is well warmed up....seems like the oil, until it gets hot, has enough viscosity to spin the PTO mechanism. Once everything is hot the PTO does not spin unless I engage it.

 

[GeoHorn]

The Ops Manual warns against engaging or disengaging the PTO under load or at high-RPM…as being abusive of the PTO clutch.

 

[North Idaho Wolfman]

Does it still do this after the tractor has been worked and everything (especially the hydraulic fluid) is hot? I have an older tractor that spins the PTO shaft until it is well warmed up....seems like the oil, until it gets hot, has enough viscosity to spin the PTO mechanism. Once everything is hot the PTO does not spin unless I engage it.

Only tractors without PTO brakes do that.
This tractor has a PTO brake.
Or I should say it's supposed to have a working brake.

 

[Ionut002]

Thank you very much for the help, the only thing to do is to hold the 540 or 540E rotation lever between gears, if I hold it between the socket it will not spin
If I do this, will it cause a defect?

 

[Ionut002]

But who applies that brake?
Oil pressure?

 

[PoTreeBoy]

Thank you very much for the help, the only thing to do is to hold the 540 or 540E rotation lever between gears, if I hold it between the socket it will not spin
If I do this, will it cause a defect?

If you are shifting while the shaft is rotating, or if you accidentally engage the clutch while it is between gears, you could do real damage.

The brake is probably engaged by the same spring pressure that disengages the PTO clutch. If you have a WorkShop Manual, it may have instructions for checking the clutch hydraulic pressure.

The brake is automatically applied when the clutch is disengaged. Heavy rotating mass at high RPM places a high load on the brake. That's why it's important to idle the tractor before disengaging the PTO.

 

[North Idaho Wolfman]

Thank you very much for the help, the only thing to do is to hold the 540 or 540E rotation lever between gears, if I hold it between the socket it will not spin
If I do this, will it cause a defect?

That's risky as what your doing is trying to hold it in a gap between the gears, where it's not supposed to stay.
There is a spring in the clutch pack that engages the brake when the clutch pack is disengaged.

 

[Ionut002]

Tomorrow morning I'll start opening it, I'll send you pictures of what I'll find there

 

[whitetiger]

The PTO clutch brake uses spring pressure to apply and hydraulic pressure to release.
The PTO clutch pack uses hydraulic pressure to apply and spring pressure to disengage.
Usually, with the symptoms you have listed the clutch or separator plates have been too hot and are warped so the pack can not fully be disengaged which overpowers the brake causing the PTO shaft to continue turning. The metal filings are probably the brake dragging.

The only way to repair it is to separate the tractor between the Range transmission and the differential case.

 

[Ionut002]

But I guess if the clutches were warped I wouldn't be able to turn the PTO by hand right?
But I can turn the PTO manually.
Anyway, I'll see what's there today

 

[Ionut002]

I discovered the problem.
I don't want to think what force was here to do this

 

[PoTreeBoy]

I discovered the problem.
I don't want to think what force was here to do this View attachment 121984 View attachment 121985

You're making good progress! Are parts readily available near you? How does the clutch look?