FEL bucket not staying up

[747driver]

My CK27 KL 130 loader bucket will not stay up...free falls down. The loader ( lift ) itself works fine. The bucket will work but I have to hold joystick in the curl position to prevent it from dumping. I was looking at the parts diagram and it shows 2 seal kits. Do I get both kits for each cylinder to do the rebuild ? I am just going to rebuild both bucket cylinders.

CK08-0100-P Seal Kit, head(No 6~11) $46.83

CK08-0200-P Seal Kit, Piston(No 13~17) $59.10 Michigan Iron and Equipment

Thanks

 

[Peter 315]

looks like it $106 each cylinder

 

[ritcheyvs]

Unless you see hydro fluid leaking out, I think you are on the wrong track.
The problem is more likely the loader control (joystick) hydraulic valve or even more likely the control cables or pivot assembly that connect the joystick to the control valves.
The first thing I'd do is look under the rubber boot at the base of the joystick to be sure nothing is broken or disconnected there.
Some of these came with plastic parts and there is a metal upgrade kit. This should show the type of mechanism you'll find at the base of the joystick:
Kioti ck 2 Updated joystick selector assembly - YouTube

 

[747driver]

Unless you see hydro fluid leaking out, I think you are on the wrong track.
The problem is more likely the loader control (joystick) hydraulic valve or even more likely the control cables or pivot assembly that connect the joystick to the control valves.
The first thing I'd do is look under the rubber boot at the base of the joystick to be sure nothing is broken or disconnected there.
Some of these came with plastic parts and there is a metal upgrade kit. This should show the type of mechanism you'll find at the base of the joystick:
Kioti ck 2 Updated joystick selector assembly - YouTube

Thanks for the tip ! I will look at the joy stick tomorrow. I can curl and dump, its just that the bucket will not stay where you had it when the joy stick goes to netural. It just falls forward and dumps the load. Couldn't you have a internal seal leakage without it leaking external ?

 

[oldnslo]

Yes the piston seals can fail with no external leakage. Is your loader like most where the cylinders extend to dump? If yes then bad piston seals can cause this problem. It could also be just one cylinder but I would probably rebuild them bo
Simple test for a leaking cylinder is to fully curl and hold the joystick to try and keep for for minute or two if seals are bad the return line from the cap end of the cylinder will get hotter than the rod end

 

[4570Man]

Unless you see hydro fluid leaking out, I think you are on the wrong track.
The problem is more likely the loader control (joystick) hydraulic valve or even more likely the control cables or pivot assembly that connect the joystick to the control valves.
The first thing I'd do is look under the rubber boot at the base of the joystick to be sure nothing is broken or disconnected there.
Some of these came with plastic parts and there is a metal upgrade kit. This should show the type of mechanism you'll find at the base of the joystick:
Kioti ck 2 Updated joystick selector assembly - YouTube

It's impossible for a cylinder to retract without loosing fluid either out the end or back through the valve. If I understand the post right the bucket is dumping which would be possible without loosing fluid out the cylinder. If he's able to hold the valve open without hitting the relief pressure I'd guess the cylinder seals are shot.

 

[ritcheyvs]

Also check if one of those ball ends (at the cable end) is lose and unscrewed some.

 

[JerryK]

I think they make a little blue pill you put into the common hyd sump now for that condition.

 

[xcgreene]

It's impossible for a cylinder to retract without loosing fluid either out the end or back through the valve. If I understand the post right the bucket is dumping which would be possible without loosing fluid out the cylinder. If he's able to hold the valve open without hitting the relief pressure I'd guess the cylinder seals are shot.

This is not really accurate. If the piston seal is bad, it will leak by internally, from one side of the piston to the other. No fluid lost or sent back to the tank. You could plug your cylinders hoses and see if it still leaks down. If it does, its your piston seals. If not, you've narrowed it down.

(edit: ^^^for anyone reading in the future, I am an idiot, and incorrect here.)

 

[4570Man]

This is not really accurate. If the piston seal is bad, it will leak by internally, from one side of the piston to the other. No fluid lost or sent back to the tank. You could plug your cylinders hoses and see if it still leaks down. If it does, its your piston seals. If not, you've narrowed it down.

There was a big debate about that a while back and I used to be of the same belief as you. It’s impossible for the rod to move back into the cylinders without loosing oil somewhere. If the rod is pulling out of the cylinder loosing oil is a possibility but it could also be bypassing the rod seals.

 

[oldnslo]

4570 is correct that with both ports blocked the cylinder cannot retract without an external leak. Reason for this is the difference in volume of the cylinder rod.

A cylinder will extend though without an external leak if the piston seals are bad.

 

[747driver]

Unless you see hydro fluid leaking out, I think you are on the wrong track.
The problem is more likely the loader control (joystick) hydraulic valve or even more likely the control cables or pivot assembly that connect the joystick to the control valves.
The first thing I'd do is look under the rubber boot at the base of the joystick to be sure nothing is broken or disconnected there.
Some of these came with plastic parts and there is a metal upgrade kit. This should show the type of mechanism you'll find at the base of the joystick:
Kioti ck 2 Updated joystick selector assembly - YouTube

Just went out and took the rubber boot off to view the joystick control It is the all metal type. Found nothing broken. Handle is alittle loose so I will tighten that up.

 

[xcgreene]

There was a big debate about that a while back and I used to be of the same belief as you. It痴 impossible for the rod to move back into the cylinders without loosing oil somewhere. If the rod is pulling out of the cylinder loosing oil is a possibility but it could also be bypassing the rod seals.

I see what you're saying now, rod going in, extra rod volume.

 

[747driver]

So I just finished looking at the joystick control. I have the all metal ball type fittings. Found nothing broken. Operated the bucket and everything responds to the joystick command normal. But when you curl the bucket back it immediately free falls forward..... unless you hold the joystick command to curl back in which it will stay up. As soon as you go back to neutral or take pressure off the curl back it free falls forward. Yes, the return line does warm up compared to the pressure line when holding the joystick in the curl up position. Looks like i need to rebuild the cylinders !

 

[747driver]

This is basically the same function as the landing gear struts on commercial aircraft I worked on. Only thing different is aircraft struts have air pressure stored on top of the cylinder filled with hyd fluid. That is whats dampens the shock when you land. So it happens once in awhile the internal seals wear out allowing air to leak down into the hyd section thus causing the strut to go flat. All this with no external hyd leaking. It was always a challenging job taking the cylinder assembly out of the strut and replacing with all new seals !!!

 

[xcgreene]

This is basically the same function as the landing gear struts on commercial aircraft I worked on. Only thing different is aircraft struts have air pressure stored on top of the cylinder filled with hyd fluid. That is whats dampens the shock when you land. So it happens once in awhile the internal seals wear out allowing air to leak down into the hyd section thus causing the strut to go flat. All this with no external hyd leaking. It was always a challenging job taking the cylinder assembly out of the strut and replacing with all new seals !!!

but in the aircraft situation you have that compressible gas. What 4570Man and oldnslo are saying, is that the extra rod volume, when the rod retracts into the cylinder, that rod takes up more space inside the cylinder. meaning less fluid can fit inside the cylinder. Something would have to give. In the aircrafts situation, it was the accumulator. The tractor does not have this

 

[747driver]

but in the aircraft situation you have that compressible gas. What 4570Man and oldnslo are saying, is that the extra rod volume, when the rod retracts into the cylinder, takes up more space inside the cylinder. meaning less fluid can fit inside the cylinder. Something would have to give. In the aircrafts situation, it was the accumulator. The tractor does not have this

My point was that you can have bad seals which leak internally but no external leaks. As you have mentioned the fluid has to go somewhere !!! It just ports it to the dump position through the bad seals. I find my career from commercial aircraft maintenance has helped me immensely..... nice I don't have to sign the logbook anymore saying "Airworthy" !!!

 

[Billrog]

My bucket was doing the same thing I cured the bucket and held it on relief for a min. then felt the top end of the cylinder and took apart the one that was warmest.This is what I found.

Loader only has 1 year warranty but the dealer gave me a new piston end. I suspect this was damaged from new. The bucket is starting to do the same thing on occasion but so far holding the cure on relief isn't heating 1 cylinder more than the other.

 

[xcgreene]

My point was that you can have bad seals which leak internally but no external leaks. As you have mentioned the fluid has to go somewhere !!! It just ports it to the dump position through the bad seals. I find my career from commercial aircraft maintenance has helped me immensely..... nice I don't have to sign the logbook anymore saying "Airworthy" !!!

lol, or having to worry about fod quite as much. I don't have to sign in an out my own tools.

 

[kwbretired]

I might be thinking backwards but the curl cylinders are sucked in in the curl position & push out to dump. If this is the case the oil in the rod end leaking back to the full bore would be less volume therefore allow the bucket to dump with a bad seal.