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Drifting stabilizer

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma
Hello to all from a new member. I’m very excited about learning to use the site and making friends.
I have owned a Case 580K series 3 for about 5 years now and love it. I clear and maintain my 20 acres and almost a mile of driveway with it and had relatively few problems with it until now. The driver side stabilizer will not hold in either direction and the cylinder has been rebuilt recently. I suspect the spool valve and/or check valve but have never attempted any of these repairs before. I’m planning on doing it myself this time and would appreciate any tips or advice that you might have to help me with this project.
Thanks Tom
 

cosmaar1

Senior Member
Joined
May 14, 2020
Messages
732
Location
Ohio
Hello to all from a new member. I’m very excited about learning to use the site and making friends.
I have owned a Case 580K series 3 for about 5 years now and love it. I clear and maintain my 20 acres and almost a mile of driveway with it and had relatively few problems with it until now. The driver side stabilizer will not hold in either direction and the cylinder has been rebuilt recently. I suspect the spool valve and/or check valve but have never attempted any of these repairs before. I’m planning on doing it myself this time and would appreciate any tips or advice that you might have to help me with this project.
Thanks Tom
Could even be that you messed up the piston seal. This would allow flow to go past both directions limiting your movement.
 

Tinkerer

Senior Member
Joined
May 21, 2009
Messages
10,154
Location
usa
After I resealed a drifting cylinder a second time, it still would not hold the backhoe up very long.

To positively determine if it is was a cylinder problem or control valve problem -> I removed the cylinders and reinstalled them on opposite sides.

The cylinder that I thought had a problem, held the backhoe up just fine when it is on the other side of the backhoe.
And the known to be good cylinder then drifted on the side that was problematic.

I used this procedure not long ago and unfortunately I am in the process of removing the control valve for a rebuild.
 
Last edited:

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma
It doesn’t hold the position that you set it at with or without the engine running. It will fall if lifted up in the storage position and it will rise underthe weight of the machine if deployed in the down position
 

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma
After I resealed a drifting cylinder a second time, it still would not hold the backhoe up very long.

To positively determine if it is was a cylinder problem or control valve problem -> I removed the cylinders and reinstalled them on opposite sides.

The cylinder that I thought had a problem, held the backhoe up just fine when it is on the other side of the backhoe.
And the known to be good cylinder then drifted on the side that was problematic.

I used this procedure not long ago and unfortunately I am in the process of removing the control valve for a rebuild.
 

Tinkerer

Senior Member
Joined
May 21, 2009
Messages
10,154
Location
usa
If the problem is still on the same side after you swap the cylinders from side to side you may need to do what is in one of my service manuals.

A visual exam of the load check valve is only part of the process of determining why it may be drifting.
This is a from a Case service manual to give you an idea of what the procedure is to service one.
The values for your stabilizer valve may (probably) be different.
1750686714457.png
 

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma
One thing I did notice when trying out the stabilizer is that if the stabilizer is down and you’re trying to move the stabilizer up very slowly in the beginning of activation of the valve the stabilizer will fall back in the opposite direction under the weight of the machine.
 

Tinkerer

Senior Member
Joined
May 21, 2009
Messages
10,154
Location
usa
One thing I did notice when trying out the stabilizer is that if the stabilizer is down and you’re trying to move the stabilizer up very slowly in the beginning of activation of the valve the stabilizer will fall back in the opposite direction under the weight of the machine.
That indicates a problem with the spool or the bore in the valve body. Or both.
There is always a chance the the rods that hold the sections together were improperly or over-tightened and cracked the valve body. IMHO of course.
I am dealing with the same issue in my own backhoe. I bought a used stabilizer section that I can put in it if I need to.

I have the backhoe off of the tractor to make it immensely easier to remove the complete valve.
I had to do some creative plumbing on the tractor hoses so that I could start it and drive it away from the backhoe without destroying the hydraulic pump.
Besides not having much time to work on it, it is too dam hot out even tho it is in my shop.
 

Simon C

Senior Member
Joined
Jul 1, 2015
Messages
2,990
Location
Rocky Mountain House , AB., Canada
Occupation
Heavy Equipment Mechanic
That indicates a problem with the spool or the bore in the valve body. Or both.
There is always a chance the the rods that hold the sections together were improperly or over-tightened and cracked the valve body. IMHO of course.
I am dealing with the same issue in my own backhoe. I bought a used stabilizer section that I can put in it if I need to.

I have the backhoe off of the tractor to make it immensely easier to remove the complete valve.
I had to do some creative plumbing on the tractor hoses so that I could start it and drive it away from the backhoe without destroying the hydraulic pump.
Besides not having much time to work on it, it is too dam hot out even tho it is in my shop.
In my experience I have seen load check valves that looked good to me , but for the sake of trying the owner spent $400 for a new load check and problem solved 100%. Not saying it is your problem, but for me it was the soulution more than once.
Simon C
 

Tinkerer

Senior Member
Joined
May 21, 2009
Messages
10,154
Location
usa
Another way to check a drifting cylinder is to fully extend or retract it, then remove the hose from the barrel closest to the piston. Then apply hydraulic pressure to it as if you want it to go further.
Leaking piston seals will allow oil to flow out of the open barrel port.
 

Tomvarner

Active Member
Joined
Jun 11, 2025
Messages
29
Location
Oklahoma
The repair shop opened her up and found a big chunk gone out of the piston seal and resealed it and I put it back on today and it works perfectly. Said they didn’t know how it happened and charged me $255. I don’t know how I could’ve done it because it leaked from day one. I paid it and left. Lesson learnt. I have learned alot thru the experience and want to thank those that took the time to visit and make troubleshooting suggestions. In the meantime let’s go digging Tom
 

cosmaar1

Senior Member
Joined
May 14, 2020
Messages
732
Location
Ohio
The repair shop opened her up and found a big chunk gone out of the piston seal and resealed it and I put it back on today and it works perfectly. Said they didn’t know how it happened and charged me $255. I don’t know how I could’ve done it because it leaked from day one. I paid it and left. Lesson learnt. I have learned alot thru the experience and want to thank those that took the time to visit and make troubleshooting suggestions. In the meantime let’s go digging Tom
That was my guess from the start. I’ve had it happen in a similar way except from the opposite end. The oring on the gland blew apart and wouldn’t hold.
 
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