JD 4200 hydraulic leak??

[duksrule]

I have a JD 4200 with a loader on the front. I don't have an actual fluid leak but there seems to be an internal leak somewhere. My loader bucket will leak down pretty fast if you don't keep hitting the lever to put it back up. My box blade on the 3 point will also bleed down after shutting down the tractor. Seems to have all kinds of lift power on the bucket it just doesn't stay up on its own. I don't see any fluid leaking out. Is there an easy fix? Any ideas?


Also I need someone to help me pick out an new loader valve because I can't seem to find mechanical parts for the one I have. It is a woods loader but they are no help with the valve.

The bucket goes up and down, forward and back and then if you push all the way down on the leaver it floats the bucket. SO... is this a single or double spool etc...

 

[arrabil]

Check JDParts for the valve. It should be the one that came with the tractor and not with the loader. The cylinders in the loader sound like they need to be rebuilt (internal leak). KennyD will hopefully be along shortly if you need more details....

 

[dfkrug]

My loader bucket will leak down pretty fast if you don't keep hitting the lever to put it back up.

What is "pretty fast"? If you don't actually see it move, it is probably OK.

If that is a Woods loader, like a 1006, the company still supports all those
units, as far as I am told. What happened when you contacted them?

 

[duksrule]

I called woods and they said that the individual dealers sorced their own valves when they put the loaders on different tractors. It is not the JD valve that mounts under the seat area. It is a generic on that is mounted up on the loader mount.

If the cylinders were leaking internal would it cause the hitch to blead down? Wouldn't it be odd for all 4 cylinders to be bad?

 

[kennyd]

Like dfrug asked, what kind of time are we talking out?

Are there any numbers or name on the valve? Can you post a picture?

 

[dfkrug]

If the cylinders were leaking internal would it cause the hitch to blead down? Wouldn't it be odd for all 4 cylinders to be bad?

You mean the loader, not the hitch, correct?

The valve is leaking internally, but a certain amount may be OK. Your valve
may or may not have a "load check", which is designed to keep pressure
in the cylinder when the control is moved back to neutral. If it has a
load check, it could be dirty or bad, or if none, then the spool may be
dirty or corroded or worn.

A whole new 2-spool loader valve with regen, boom float, and a joystick
is commonly available. This one is from our friendly sponsor, SurplusCntr
for about $250.
https://www.surpluscenter.com/item.asp?item=9-7401&catname=hydraulic

 

[duksrule]

It leaks down pretty fast. The bucket tilt will actually let it tilt and stuff fall out if you don't keep hitting the stick. Also if you have the bucket all the way off and shut off the tractor, it will be on the ground within 10 minutes. Back when I got the tractor years ago it would hold the bucket up for weeks without the tractor running.

Are you saying that the check valves that hold the pressure are in the valve itself?

 

[duksrule]

Here are a few pictures of the valve. I need to rod ends at the top (there are 3) that connect the joystick to the valve. Mine are worn and pop out if you move the lever to far.

I guess I also need a rebuilt kit if this is the reason that my bucket leaks down.

 

[Egon]

Check all of the joystick linkages for wear etc. They might be your problem.

 

[kennyd]

Machine kept outside? Those heim joints look nasty! As do the hoses.

I assume the are no QD's (quick disconnects) between the valve and the cylinders?

 

[duksrule]

Machine kept outside? Those heim joints look nasty! As do the hoses.

Yes and Yes.

I assume the are no QD's (quick disconnects) between the valve and the cylinders?

It does have QDs but none of them leak fluid.

 

[kennyd]

It does have QDs but none of them leak fluid.

Excellent. Raise the bucket and set it on something-like a truck bed or retaining wall.

Now, shut the tractor off, relief pressure by moving the joystick-then disconnect the 4 QD's. now back the tractor away so the bucket is in the air and see if it still leaks. Yes-the cylinders are leaking internally. No-the valve is bad.

 

[duksrule]

Thanks, I'll try this and let you know what happens.

Is it possible to rebuild the cylinders at home? I can do pretty much anything when it comes to a car.

 

[kennyd]

Thanks, I'll try this and let you know what happens.

Is it possible to rebuild the cylinders at home? I can do pretty much anything when it comes to a car.

Sure, it's not that hard...do some searching in the hydraulics forum-there are plenty of threads there, try key words like "rebuild" and "seal". Posting pictures of the cylinders, especially the end where the rod comes out will help us help you.

 

[banjodunn]

G'day don't know about over there but here those rose joints ( as we call them i think you call them heim??) are readily available at most specialist bearing supply shops far cheaper than genuine


Jon

 

[dfkrug]

Are you saying that the check valves that hold the pressure are in the valve itself?

I do not know your valve, but the hex caps on your 2nd photo in post
#8 are most likely "load checks". If you remove one, there is probably a
spring and a ball in there. Maybe some crud, too. Those hoses look
awful, but you don't need me to tell you that.

I see the Power Beyond port on your valve is not used. I wonder how
the loader valve is connected to the rest of your hydraulics. Does your
tractor have any of the stock "SCVs" under the seat on the right side?

 

[Willl]

Excellent. Raise the bucket and set it on something-like a truck bed or retaining wall.

Now, shut the tractor off, relief pressure by moving the joystick-then disconnect the 4 QD's. now back the tractor away so the bucket is in the air and see if it still leaks. Yes-the cylinders are leaking internally. No-the valve is bad.

That won't work.

http://www.tractorbynet.com/forums/hydraulics/179487-cylinder-drift.html

 

[kennyd]

That won't work.

http://www.tractorbynet.com/forums/hydraulics/179487-cylinder-drift.html

It does work until the pressure is equalized.

 

[duksrule]

I do not know your valve, but the hex caps on your 2nd photo in post
#8 are most likely "load checks". If you remove one, there is probably a
spring and a ball in there. Maybe some crud, too. Those hoses look
awful, but you don't need me to tell you that.

I see the Power Beyond port on your valve is not used. I wonder how
the loader valve is connected to the rest of your hydraulics. Does your
tractor have any of the stock "SCVs" under the seat on the right side?

Not sure what is under the seat. I have never had it off. I know that the loader is plummed in, there is also another actuator under the tractor that use to be used to raise the belly mower and is controlled by a different valve and then there is a set of QDs on the very back that look like you could plug something into it.

Yes I know the hoses look bad. Sad thing is 2 of them are only 2 years old. Unfortunatelly I don't have a place to store it. It has been a work horse of a tractor for me though.

 

[dfkrug]

Not sure what is under the seat. I have never had it off. I know that the loader is plummed in, there is also another actuator under the tractor that use to be used to raise the belly mower and is controlled by a different valve and then there is a set of QDs on the very back that look like you could plug something into it.

Your tractor comes with a 1-spool or 3-spool monoblock valve attached to
the main gearbox's right upper side. Normally, hydraulic pressure to operate
your valves goes from your implement pump to your factory valve(s), and
then from that valve's PB port to the 3-pt cyl valve. If you add an
aftermkt valve, it must be plumbed in series with the other valves, or get
its hyd power from a diverter. Since your Danfoss valve does not use
its PB port, it should be plumbed off a diverter. If it is not, its OUT
port (which is not designed to handle high pressure) may be plumbed to
the IN port of the SCV(s) or the 3-pt, which is not correct.

Something does not seem right here.