hydraulics on loader

[tim in alaska]

hello folks... I have a loader on a 9n that has positive pressure on the bucket. the bucket will weep down when under load. the bucket hydro are controled by a gresen hdro valve. there is a front portion held by 4 screws and back where the control lever is . I assume that there is a need for some kind of repacking or replacement some kind of seal. sorry for the long winded intro but can this be done from front or back and do i have to bleed down the system some way before removing either. there is no problem with the cylinders leaking. as you can see i am not much of a mechanic. thanks in advance for your help. Tim in alaska I could not locate model number of valve.

 

[Ultradog MN]

You would lay the bucket on the ground and push/pull both levers to release any residual pressure in the system.
The spool will need to be removed from the back end - where the screws are. You will need to first remove any linkage between the handle and spool ( the part that slides in and out) from the other end. I can't say exactly what you will find in there but all those valves are pretty simple. You probably just need orings and or seals. You might match them up at a hardware store or auto parts place. If there is a hydraulic shop near you they would probably heve them too.
Don't let someone gouge you rebuilding it.
Loader valves are pretty simple and can be bought new for not a lot of money.
Where are you in AK?
I spent 2 1/2 years in Anchorage back in the 80s.

 

[TheOldHokie]

(quoted from post at 18:52:50 09/12/13) hello folks... I have a loader on a 9n that has positive pressure on the bucket. the bucket will weep down when under load. the bucket hydro are controled by a gresen hdro valve. there is a front portion held by 4 screws and back where the control lever is . I assume that there is a need for some kind of repacking or replacement some kind of seal. sorry for the long winded intro but can this be done from front or back and do i have to bleed down the system some way before removing either. there is no problem with the cylinders leaking. as you can see i am not much of a mechanic. thanks in advance for your help. Tim in alaska I could not locate model number of valve.

A double acting cylinder can and often does leak internally resulting in leak down with no sign of an external leak. Control valves not so much. I'd double check the cylinder to make sure it is holding before I attacked the valve. A simple diagnostic is to roll the bucket up and support it then remove the dump hose from the bucket cylinder and install a plug in it's place. If the cylinder leaks down with the plug installed it is an internal leak in the cylinder. A new or rebuilt cylinder is a lot cheaper than a leaking valve.

TOH

 

[Bob]

Dog, I'm with Hokie in that it's a cylinder leakage problem.

And, the only seals that can be replaced in a typical spool valve are there to prevent EXTERNAL oil leakage.

The internal hydraulic pressure valving seals because it's a precision ground, selective fit.
NO way to repair it if there's INTERNAL damage/leakage.

 

[Ultradog MN]

Thanks Bob, Hokie.
I'll defer to you guys' analysis.

 

[greywolf224]

I had this same type of an issue. I run a Dearborn 19-70 loader on my 8N and when I lifted the empty bucket up so that I can drive the tractor from one place to another, I had to constantly keep rolling it up up because it slowly dropped. Average about 2 inches a minute.
I thought that it was the control valve but decided to tackle the cylinders first. After rebuilding both cylinders problem stopped.

 

[tim in alaska]

thanks for your reply underdog,,,I am located in willow about 65 miles north of anchorage tim