TC40D loader hydraulic issues

[Glennmerkel]

Hello all. I'm hoping some of you out there will be able to help with this problem. Over the pasts few months, my bucket has begun to uncurl rather quickly. The arms do drift down but it is so slow that it isn't an issue. I use the tractor during the winter to move my firewood around and I'm concerned now about moving it this year with how quick it starts uncurling. You're constantly having to touch up the hydraulics to keep the bucket our pallet forks level. I would love to get the factory service manual but with a new addition to the family, my financial department (wife) watches the funds more closely.
Here's what I know so far: with any attachment on or off, it will still uncurl itself. It uncurls faster with an attachment on but will still uncurl with it off. This also occurs with the tractor shut off. The hydraulic oil and filters have about 200 hrs on them and the fluid is at the appropriate level. I'm not seeing hydraulic fluid leaking anywhere on the ground. I disconnected the quick connects for the curl/uncurl and was unable to move the bucket so that leads me to believe the rams are not the issue.
So I know that fluid is leaking by somewhere, I just don't know where to start looking. Any help you guys can offer I would greatly appreciate.

 

[J_J]

Is your valve cable operated, and if so, have you checked if the cables need lubed or checked for binding?

If it is lever operated, have you checked to see if the valve spool was centering ?

If the spool isn ot centering, you will have some leakage, and if the spool is leaking, you will have some leakage causing the bucket to move on it's own.

To check for spool leakage, remove the cyl hose from the curl spool and in neutral, check for leakage.

The non centering might be due to the springs under the cap on the bottom of the valve. Inspect, clean and replace parts if needed. Lube wel.

Your cyl piston seals could be hard, brittle cracked, just worn out. l

 

[Glennmerkel]

Thanks J_J. It is lever operated so I'll check the spool valve. Just so I have it right, disconnect the steel line coming into the spool valve for the curl operation. Then start the tractor and see if any fluid is leaking out while running. Thanks again.

 

[J_J]

Either the metal line or rubber hose.

In neutral, no fluid should be coming from the FEL work ports.

 

[wolfpack2]

A cleaner and easier way to check is swap the lift and curl hoses. Just unplug the hoses using the quick couplings and reverse the connections. If the lift cylinders now drop at a fast rate, its the valve. If the curl cylinders still drop, it's the cylinders and they most likely will need to be rebuilt.

 

[Glennmerkel]

Ok. I'll check it out over the next few days and let you know what I find. Thanks again.

 

[Glennmerkel]

Ok guys so I did some checking today. I didn't have the time to to loosen the steel line going into the spool valve so I reversed the lines like wolfpack2 suggested. Nothing happened at all. The lift cylinders nor the curl cylinders dropped at all. That was with the tractor shut off for over an hour and nothing moved. I did not have any implement attached to the front so there was no weight to help the process along. I put everything back the way it should be and still nothing drifted. Once I started the tractor and was able to use the hydraulics, the curl was drifting because I was able to keep touching it up to retract the rams all the way. It still doesn't act like it's the cylinder though. A few days ago I had disconnected the hydraulic quick connects for the curl while I had the pallet forks attached and they didn't drift at all. I was jumping on the forks and nothing moved. So from what you guys had said and what I'm seeing it's like it's not the cylinders or the spool valve. I guess it could be the cylinders but it is only evident while the tractor is off with a front implement attached. Right now I have the pallet forks attached with the line quick disconnects disconnected to see what it looks like in the morning. What do you guys think?