Kubota BX25 FEL falls under own weight

[dubojr10]

2013 BX25D with apprx. 200 hrs of easy residential use. No previous FEL issues. No FEL cylinder or control valve external leaks.


FEL falls under its own weight. It does stop eventually I'm assuming once the pressure equalizes to the load. I have removed the FEL and tested the hydro pressure on the quick disconnects thus eliminating the possibility of FEL cylinder issues. Gauge indicates the same issue. Pressure goes up with the lever and once lever is released and returns to center the pressure falls. Happens on the up and down movements of the FEL. Front bucket curl function seems to be fine. Pressure rises and holds. I did remove the spool for the FEL lift function and no damage was found. I mistakenly did not look closely at all the other components while the spool was removed. I have doubled checked the PTO selection lever to make sure it was not in the middle of a selection. Only other hydro issue is the backhoe bucket will swing to left side on its own without the travel pin in place. I believe this to be unrelated to FEL issues cause it's done that since new.

I'm thinking the FEL control valve needs to be rebuilt or replaced. Am I on the right track..?

 

[oldnslo]

How far do the FEL cylinders move before stopping?

If you use the FEL to lift the front of the tractor off the ground will the loader stay in position or does the front of the tractor drop?

 

[LD1]

how long does it take to fall on its own? inches per hour? inches per minute? inches in seconds?

Not much on a valve that can be rebuilt to solve an "internal" problem.

 

[dubojr10]

How far do the FEL cylinders move before stopping?

If you use the FEL to lift the front of the tractor off the ground will the loader stay in position or does the front of the tractor drop?

Bucket drops approx. 8"-12" with an empty bucket.

If you lift the front tractor wheels off the ground, it will set the wheels back down in maybe 10-12 sec.

 

[dubojr10]

how long does it take to fall on its own? inches per hour? inches per minute? inches in seconds?

Not much on a valve that can be rebuilt to solve an "internal" problem.

It's prolly an inch per second or more with tractor running. I get the typical leak down during shut down periods but I consider that normal.

 

[dubojr10]

Maybe this would be helpful for discussion too.

 

[LD1]

I'd take the load checks out and see if one of them has a nick or damage on the seat or something obvious.

You say the spools valves themselves look good, what do the bores look like? The spools are usually a good bit harder than the cast iron body/bore that they operate in

 

[dubojr10]

I'd take the load checks out and see if one of them has a nick or damage on the seat or something obvious.

You say the spools valves themselves look good, what do the bores look like? The spools are usually a good bit harder than the cast iron body/bore that they operate in

I will need to spend some time looking at your suggestions here. Once I seen the diagram I too felt the need to inspect the checks for damage.

I wish I had a better understanding of hydro terms and how the system operates. I only checked the spool that was responsible for the up and down movements. I'll have to dissemble things again and inspect all the control valve components more closely.

Are your initial thoughts though that it is a control valve issue?

 

[LD1]

With no external leaks....the control valve is the only thing it can be

 

[oldnslo]

dubo,
A leaking load check would typically cause a different issue than what you are reporting.

I suspect a failing cylinder seal is your problem. Do you have a jack that you can put under the loader bucket?
If yes raise the jack fully.
Place the jack under the bucket.
Lower the bucket onto the jack and shut the tractor engine off.
Move the joystick like you are trying the lower the bucket to relieve the pressure in the circuit.

Follow the hydraulic hose from the cap (lift) end of the cylinder back to the quick disconnect and uncouple only this quick disconnect.

Lower that jack and watch to see if the loader drifts down. If it drifts down you have a bad seal on one of the lift cylinders.

if no movement, your valve is leaking.

You will have to lift the bucket slightly with the jack to reconnect the hose.