Control valve BT 900 Backhoe

[jasowiii]

Looking for advice on repair of my backhoe stabilizer control valve on an L35.
The stab bleeds down in a few seconds.

I believe the problem is in the "lock" valve portion of the control valve assembly. The valve assembly is a Husco 5000 F104C. I think the problem is in what they call the "pilot operated check section". Note that I can lift about a ton with the stabilizer and it hold it up for hours, also the other stabilizer is rock solid too.
I rebuilt the cylinder first as it was leaking a little. Not any more.
The control valves do not leak a drop (externally). Including the seal on the cap, spring, ball portion of the "lock".

Kubota sells a seal kit 75595-63792 but I don't see how it would work. It has various size orings and a backer. The lock outs are hard chrome balls a spring and a seat. It makes no sense to me where the orings and backer would go???

Any ideas?

 

[North Idaho Wolfman]

Does this answer your question?

 

[jasowiii]

Wolfman,
No but maybe???

I am almost positive items 480 and 470*570 are the bad actors. My problem is getting to them or getting to anything that even looks like them.

When I take the "cap" off, I see a spring. I remove the spring, I see a ball. I remove the ball, I see a seat. None of this resembles the image. If you look at the part number list associated with the exploded view you sent you will see the seal kit 75595-63792. But again, I don't see how it would work. It has various size orings and a backer which I don't figure would do anything for the spring/ball/seat set up.

Now for the maybe...
I have never looked at the exploded view zoomed in as close as in your attachment. If you look closely at 470*570 you see what looks like a double hex (big/small). When I remove the small one I get the spring/ball/seat. If I remove the big one maybe...

Problem is that I have tried to and it does not budge. It looks like the bigger hex is part of the valve casting so I stopped. That and it is a 1" hex and less than an 1/8" tall and my wrench slips off. I'll try the bottom one with more torque and warm it up a little with a heat gun and see what happens.

Jim

 

[jasowiii]

More info for reference.
Below is a link to the Husco Literature.
http://www.huscointl.com/wp-content/pdf/5000.pdf

 

[jasowiii]

Go figure...

It makes sense that the oring could end up in the filter but I would not think the backer would disappear??

Hope this helps someone in the future. My advice is remove the spool seal retainer flange so a 1" socket can sit flush with the valve body before reefing on the hex. It came right out with a breaker bar once I got a good hold on it.

Jim

 

[North Idaho Wolfman]

Use a mirror if you need too, to look up into the valve section and make use the O-ring and wiper are not just lodged up in there.

Replacing those 2 parts should fix you right up.