FEL LA481 Control valve - Seal replacement worth a shot?

[ArtsmeiH]

Hello,

I have a FEL that won't hold it's tilt. When I fully curl the bucket back, it will slowly start to dump. Once it gets past a certain point it will dump rapidly. I think I have narrowed it down to a control valve(B00101) and not a cylinder issue. After swapping the hoses around on the control valve, I was no longer able to curl the bucket. The boom raise and lowering seem to be working fine. After looking at the parts diagram on Messicks, it looks like I might be able to rebuild or replace the seals on the valve rather than replacing the whole unit. Looking for some guidance on multiple fronts here guys, and eager to learn.

Will it fix my issue? Is this the issue?
How hard would the job be?
How do I know what seals or parts to replace for just the one malfunctioning
valve? Or Should I replace everything?

Pics
https://imgur.com/a/G39eibD



Parts diag- I think.
https://www.messicks.com/ku/85591?sectionId=221297&diagramId=379157


Any help would be great.

Thanks guys!

 

[ArtsmeiH]

I should note for clarification that I swapped the boom and bucket lines around first.

So, top left for top right, and bottom left for bottom right. This caused the boom to only lift. I had to loosen the bottom line to bleed fluid, and then it slowly lowered.

I went back to each line in its default spot, and then swapped the top left for the bottom left. This resulted in the bucket no longer being able to curl, but the boom started working correctly again. The issue seems to be on the left side lines. Just not sure if it is the top or bottom.

 

[Dave_eng]

Putting your leaking down bucket issue aside for a minute, it sure sounds like you have hoses in the wrong place.

Everything should move normally when you swap the hoses except that the arms will move when you call for the bucket to move and vice versa. The fact that this is not happening indicates you have hoses crossed somewhere

Dave

 

[ArtsmeiH]

Putting your leaking down bucket issue aside for a minute, it sure sounds like you have hoses in the wrong place.

Everything should move normally when you swap the hoses except that the arms will move when you call for the bucket to move and vice versa. The fact that this is not happening indicates you have hoses crossed somewhere

Dave

When hooked up in the "default" spots on the control valve, everything does work as normal. Except my bucket slowly dumps when not touching the control stick. I can dump it if i want and curl it back, it just wont stay.

Do I need to swap hose's in multiple locations when moving them around on the control valve? It seemed like what ever was connected on the left side, only one function would work. example being it will lift but not lower, or dump but not curl. Maybe I am going about this wrong. Still a newbie and this is my first experience with these lines and valves.

Thanks!

 

[ArtsmeiH]

Though in normal operation...it is slow to curl, moving fast if I increase RPM's. Releated?

 

[Dave_eng]

Your loader valve has two internal circuits.

Each of these circuits has two hoses running to loader cylinders which are plumbed together in pairs to make them work together. A pair for the lift arms and a pair for the bucket.

Hydraulic cylinders can develop more push or pull in one direction than the other. This is because the push rod of the cylinder occupies some of the face area the fluid presses against to generate a push or pull.

When you mix up hoses, the cylinder pair is no longer having fluid do one motion while at the same time allowing the fluid on the other end of the cylinder to escape. There is an unbalance of forces which is why you see a bit of movement.

Do your loader hoses have quick couplings to allow easy removal of the loader from the tractor?

Dave

 

[ArtsmeiH]

I believe so. It looks like I have 3 with quick connects. One quick connect is right off the control valve and two underneath the right side cab floor. Maybe I mixed the two underneath around? Is there a place to see a diagram of how it should be connected?

 

[ArtsmeiH]

Do your loader hoses have quick couplings to allow easy removal of the loader from the tractor?

Dave

Looking closer at it and it appears that the quick disconnects are setup in a way that I am unable to swap them. One hose has it on the hose the other has it on the box. The third in inline.

 

[old and tired]

So did you swap Hose 1 for #3; AND swap hose 2 for #4 in the photo? Just trying to understand...

 

[ArtsmeiH]

So did you swap Hose 1 for #3; AND swap hose 2 for #4 in the photo? Just trying to understand...

If we are saying top right is 3 and bottom right is 4, yes.
(sorry I just noticed you labeled them in your picture. Thanks!)

So I swapped,

1 with 3 and 2 with 4 - lift worked but I could not lower the bucket, I think the bucket still dumped as well(on it's own).

Then I put everything back to "default" and swapped 1 for 2 - Bucket would no longer curl but raise and lower worked again.

Hope I am explaining this well.

I really appreciate you guys taking the time to respond!

 

[Dave_eng]

In looking at your initial photo, I see pairs of lines have tape around them. Green tape and white tape.

These pairs of lines are to be adjacent to each other vertically.

Think of the valve as being two side by side valves with a vertical dividing line down the middle.

The green tape lines need to be on one side of the dividing line and the white tape on the other side.

Dave

 

[old and tired]

Will it fix my issue? Is this the issue?
How hard would the job be?...

I don't know, I have not done it but I would give it a try. $100 or so for seal kits vs. over a grand for a new valve, worth the chance.

Also, would be great to document it!!! If you do not feel confident, are there hydraulic shops near you that you can take it to?

 

[jenkinsr]

The valve in the diagram has O ring seals at the end of the spool to stop fluid from leaking out end of valve. Internal seal is by very close tolerance between spool and housing. Top of valve has two plugs, under the plugs are a spring and poppet type valve. Could be broken spring or poppet not sealing properly. If internal seals on bucket cyl are bypassing it could drift down.