Kubota L48 TLB stabilizers / outriggers help

[teabor]

What bothers me is there seems to be a check valve in the diagram for the RH
outrigger cyl base A3 (extend), but not the LH cyl. I assume the LH cyl is
just above the RH in the diagram.

The lift problem you have affects both cylinders, so the culprit should be something
that both share. I like STONEHALLER's theory about the lockout valve (check valve),
but I do not see how that can account for both cylinders failing to lift properly.

dfkrug, not sure what you were looking at but both cyl have the same set up. Yes, the LH is above the RH.

 

[J_J]

Appears to be working to me.

You had max pressure at the end of stroke.

Why not put the hyd gauge in a tee in the IN port of the first valve in the flow path to check pressure.

It will then tell you the pressure of any hyd component in the circuit.

 

[Leejohn]

You might be getting binding if the piston is loose, but if it is loose you should be getting oil coming out of the open port when you done the cyl test.

 

[teabor]

You might be getting binding if the piston is loose, but if it is loose you should be getting oil coming out of the open port when you done the cyl test.

Leejohn, could it be loose during the stroke and squaring up at the end of the stroke (sealing correctly)?

 

[teabor]

Appears to be working to me.

You had max pressure at the end of stroke.

Why not put the hyd gauge in a tee in the IN port of the first valve in the flow path to check pressure.

It will then tell you the pressure of any hyd component in the circuit.

I will give that a shot. Give me a couple of days.

 

[Leejohn]

Leejohn, could it be loose during the stroke and squaring up at the end of the stroke (sealing correctly)?

Just maybe, on that return something is building pressure and shouldn't be that high. If the shaft was bent you would have the high pressure going both ways. So I guess the only thing left is the piston. Hook the pin back up and see if the pressure well build when the foot hits the ground, if not then the piston is bypassing.

 

[dfkrug]

dfkrug, not sure what you were looking at but both cyl have the same set up. Yes,
the LH is above the RH.

OK, I see it now. The error I made was the RH was activated, and the LH was not.

As for the videos you posted, no way should you see 2000psi on the extension of a
disconnected cyl with no external load. That points to a severe fluid restriction, or
a bent rod/binding piston.

 

[teabor]

Just maybe, on that return something is building pressure and shouldn't be that high. If the shaft was bent you would have the high pressure going both ways. So I guess the only thing left is the piston. Hook the pin back up and see if the pressure well build when the foot hits the ground, if not then the piston is bypassing.

Leejohn, here is a video of the hyd connected back to the stabilizer and cycling. No bypassing that I can see (guage stays at zero when relief hits). Guage is teed into the retraction line.

https://www.youtube.com/watch?v=vlJP-UVrylc


Maybe I should look at the lockout portion of the valve and see if there is anything stopping the proper operation.

 

[Leejohn]

Leejohn, here is a video of the hyd connected back to the stabilizer and cycling. No bypassing that I can see (guage stays at zero when relief hits). Guage is teed into the retraction line.

https://www.youtube.com/watch?v=vlJP-UVrylc


Maybe I should look at the lockout portion of the valve and see if there is anything stopping the proper operation.

That seems like it takes to much psi to even lower and 2000psi just to lift back up and is slow to build up to 2500 psi.it shoul pop right to max.. That foot can't weigh that mutch. Should have the gauge on the other hose so you can see the psi when it is tring to lift. You were getting 2500psi with cyl all the way out but it seem to be not getting it at half way. You can't see on the gauge if the piston is bypassing when it's on the rod side and you are putting pressure on the base end because that side would be open to tank. If you got something between the cyl and leg you could of maybe egged shaped the cyl. I would think the leg would drop by itself with eng off and you move the down level.
I can't help on the lockout valves, but I think you should be checking them like stonehaller said. I took it that you might of done that.

 

[Stonehaller]

It sure looks like the valve is working correctly from your videos. If you want to defeat the lock out valve, take out the small, bullet/arrow shaped poppet valve and spring on each side. Leave the main poppet installed so the travel of the lockout spool is contained. But I think Dirthog had your answer back in post #4.

I think you will find there is nothing wrong with them mine has been that way since day one. They will hold the machine up all day but will not pick it up more than a few inches believe it has to do with the geometry when you extend them.