Kubota M59 hydraulics screwed up after service

[lwm]

Hi all,

Me and my mechanic recently went through all 3 of my tractors (B21, M59, KX-161-3SS) and did fluids and filters.
Somehow we screwed up the M59. Here are the symptoms:

a) It has a position control valve and after the service the arms don't start going up until you are at 7-8, they should go up at 2. I did loosen the nut that controls that valve so it turns more freely but I don't see how that would cause the rest of what I'm seeing.
b) All of the rest of the problems are when the 3 point is all the way up and they go away partially or entirely if I lower the 3 pt.
c) Lifting the loader is noisy, sort of a screeching sound.
d) Lowering the loader is really slow, way slower than normal.
e) The tractor has no power going forward - it will move but it's like it is in high while you are trying to go up a steep hill, doesn't want to move.
f) I have an extra remote that runs a grapple, the grapple won't open and close.

Like I said, if I lower the 3pt then things get better. So I wondered if it just wasn't topped off enough but I checked that and it has more than enough fluid.

Now I'm wondering if we got the wrong filter in there and we don't have enough flow but I don't see that if changing the 3pt changes how it behaves. So I'm at a loss.

Anyone have any ideas?

 

[J_J]

I am thinking your 3pt is causing back pressure.

Is your 3pt spring loaded to neutral?

If your lever does not go back to neutral, it is causing flow to the 3pt and producing back pressure.

Everything upstream will act odd.

The relief should only come on when you are making the valve see max load.

Changing the fluid should have not made a mess of things.

You should only have to purge the air and then been good to go.

Did someone mess with adjustments of any kind?

 

[dsgsr]

Make sure the 3pth/backhoe levers (2, just behind and under the drivers seat) are in the proper position. Fully forward for backhoe operation or fully to the rear for 3pth operation.

David

 

[lwm]

I am thinking your 3pt is causing back pressure.

Is your 3pt spring loaded to neutral?

Did someone mess with adjustments of any kind?

I don't have the basic valve or the quarter inching valve, my tractor has a position control valve.

My mechanic played with it and said the "porter valve was squealing" and made an adjustment so that the position control arm couldn't go as far back and that seems to have fixed most stuff. Weird.

If anyone else has an m59 or a b21 can you tell me when the implements start to lift? On both mine it is around 5 which makes me wonder what the point of positions 1-5 are, do they do anything?

 

[lwm]

Make sure the 3pth/backhoe levers (2, just behind and under the drivers seat) are in the proper position. Fully forward for backhoe operation or fully to the rear for 3pth operation.

Good thought David but I had checked that. Went around the whole tractor looking for anything that was set wrong and that was OK as was everything else I could see.

 

[Tags]

This is just a shot in the dark, but could it be the quick couplers that feed the hoe and plug back into the machine when its removed? Maybe try unplugging them and then plugging them back in?

 

[J_J]

If you want to know if the 3pt valve is causing any pressure, then install a hyd gauge in a tee in the IN port of the FEL valve.

With all valves in neutral, there should be no or very little pressure indicated.

When you use any hyd valve, cyl, or motor, the gauge will indicate the pressure.

You can also use the gauge to monitor and troubleshot the hyd system.

Hyd gauge set should run abut $30 to $50.

 

[lwm]

So the problem seems to be "fixed" though I don't understand why.

There is a stop on the position control valve lever and my mechanic adjusted it to not let the lever go all the way back. So far, that seems to have fixed it.

His claim is there is a "porter valve" controlled by that lever (is that a thing?) and it was working hard when the lever went all the way up. He says he heard it.

Anyone know anything about that?

Thanks for the suggestion to get some gauges, will do that now.
And to the person suggesting the backhoe connectors, I have a scraper blade on so it's not the connectors.