Loader will not lift

[Cesky]

Hello,
I have a Kubota B2650, LA534 loader, and a Claw Grapple SGC0554 attached. My 3- point hitch (Up/down) operates. The attached grapple (open/close) operates. The loader tilt (L/R) operates. However, the loader up/down) does not. I have cleaned and rechecked the hydraulic hose connections, (A,B,C,D) and hydraulic fluid levels. I have tried moving the control lever in all positions, including float position. The valve lock is unlocked.
I was operating normally and then noticed a light coating of oil spray around the speed control pedal. I discover a hydraulic leak from the 3rd function valve. There was a loose Allen wrench screw on the electric hydraulic solenoid valve unit. I assume the engine fan sprayed the oil leaking from the valve unit that was evident around the pedal. I have not discover any other leaks. I do not know if there is a connection but after moving a tree with the grapple my loader would not lift. I was able to get a slight loader lift, 3-4 inches when I forcibly moved the tractor to a different location. However, currently the loader is on the ground and will not lift up or down. Does this situation sound like a main loader valve issue?
Thank you for any advice.

 

[TheOldHokie]

Hello,
I have a Kubota B2650, LA534 loader, and a Claw Grapple SGC0554 attached. My 3- point hitch (Up/down) operates. The attached grapple (open/close) operates. The loader tilt (L/R) operates. However, the loader up/down) does not. I have cleaned and rechecked the hydraulic hose connections, (A,B,C,D) and hydraulic fluid levels. I have tried moving the control lever in all positions, including float position. The valve lock is unlocked.
I was operating normally and then noticed a light coating of oil spray around the speed control pedal. I discover a hydraulic leak from the 3rd function valve. There was a loose Allen wrench screw on the electric hydraulic solenoid valve unit. I assume the engine fan sprayed the oil leaking from the valve unit that was evident around the pedal. I have not discover any other leaks. I do not know if there is a connection but after moving a tree with the grapple my loader would not lift. I was able to get a slight loader lift, 3-4 inches when I forcibly moved the tractor to a different location. However, currently the loader is on the ground and will not lift up or down. Does this situation sound like a main loader valve issue?
Thank you for any advice.

Is there any indication the loader is trying to lift? Do the hoses move at all when you operate the loader control? Any change in sound from the tractor or loader valve? You could try removing the grapple and see if that makes any difference. If I were faced with that I would disconnect the lift cylinder hose at the end of the boom (connection circled in red) and check for flow when the loader valve is operated.

WHOOPS - circled the wrong connection - should be the other end of that cylinder -numbers 30 and 80.

Dan

 

[ruger1980]

Swap the tilt circuit hoses with the lift hoses and see if the problem moves. That will determine of the issue lies with the valve or cylinders.

 

[Cesky]

Thank you for the response,
I disconnected the grapple, no change. The loader when activated U/D will move or respond 1/2" either way. I disconnected the cylinder hoses #30/80. There is a strong flow moving the control lever "down".
I checked the other side as well #60/90. There is a strong flow moving the control lever "up"

 

[TheOldHokie]

Thank you for the response,
I disconnected the grapple, no change. The loader when activated U/D will move or respond 1/2" either way. I disconnected the cylinder hoses #30/80. There is a strong flow moving the control lever "down".
I checked the other side as well #60/90. There is a strong flow moving the control lever "up"

Dahum! You have flow but no lift. I see 3 potential possibilities:

1. You have flow but no pressure. Given that the bucket and 3rd functions work that seems unlikely.
2. You have pressure but the return path to tank is blocked. That can be tested by disconnecting the rod end (return) hose (70/30) and put it in a bucket. If the loader will raise with the hose disconnected you have identified the problem.
3. If #2 is eliminated then perhaps the loader frame is mechanically jammed. I would test that by putting the loader valve in float and lifting the bucket with another tractor or a hoist of some sort.

If you have a pressure gauge there are a couple of other tests you could try.

Dan

 

[Cesky]

Swap the tilt circuit hoses with the lift hoses and see if the problem moves. That will determine of the issue lies with the valve or cylinders.



Hello,
The original hose connections were configured A) White: Up/Down, C) Blue: R/L, D) Red: R/L, B) Yellow: Up/Down.
I switched Yellow and White to the C and D ports
I swapped Blue and Red to the A and B ports.

The loader now lifts but I have no tilt.

Therefore, do I likely have a main loader valve issue?

 

[Cesky]

Dahum! You have flow but no lift. I see 3 potential possibilities:

1. You have flow but no pressure. Given that the bucket and 3rd functions work that seems unlikely.
2. You have pressure but the return path to tank is blocked. That can be tested by disconnecting the rod end (return) hose (70/30) and put it in a bucket. If the loader will raise with the hose disconnected you have identified the problem.
3. If #2 is eliminated then perhaps the loader frame is mechanically jammed. I would test that by putting the loader valve in float and lifting the bucket with another tractor or a hoist of some sort.

If you have a pressure gauge there are a couple of other tests you could try.

Dan

I swapped the hose connections as recommended from another post. The loader will now lift (Up/Down), but I lost the tilt (R/L) function.
I previously had put the loader valve in float and tried to lift the loader with a floor jack. The loader arm would not raise independently.

 

[RCW]

Don't want to steal ruger's thunder, but yes, since you swapped the Wh/Y with the R/B, it does sound like a valve.

As I'd be guessing quite a lot, I don't want to send you down a rabbit hole for further troubleshooting the valve, or other possible causes.....

ruger1980, Dan, and many others are very good at hydraulic stuff, and valves specfically. I need to defer to them so I don't do you a disservice.

 

[ruger1980]

I would verify that your boom spool is actually moving when moving the lever. I am not sure if you have a cab and possibly cable operated controls. Even though you say you have flow at the cylinder hose I would verify the travel.
Pretty sure you don't have port reliefs in that loader valve so that should not be a possible fault

 

[TheOldHokie]

I swapped the hose connections as recommended from another post. The loader will now lift (Up/Down), but I lost the tilt (R/L) function.
I previously had put the loader valve in float and tried to lift the loader with a floor jack. The loader arm would not raise independently.

Let me double check this - you placed the valve in float and you cannot raise the loader using a floor jack?

If so your loader is being held down by something and you need to start eliminating possibilities. It could be hydraulic or mechanical. I would suggest you try what I suggested earlier - disconnect the return lines from the loader cylinders and see what that gets you. You could also try unpinning one end of the lift cylinders and trying the jack again.

Dan

 

[whitetiger]

You have a failed coupler on the valve, either the Raise or Lower coupler will exhibit the symptoms you have.

You can either get one new tip and replace either one on the valve and try it. If that made no difference, replace the other one with the couple you removed and try it. Or you can get 2 new couplers and replace both of the boom Raise and lower couplers at one time.

Dispose of the failed coupler so later someone does not try to use it.

 

[Cesky]

I would verify that your boom spool is actually moving when moving the lever. I am not sure if you have a cab and possibly cable operated controls. Even though you say you have flow at the cylinder hose I would verify the travel.
Pretty sure you don't have port reliefs in that loader valve so that should not be a possible fault

I do not know how to verify if the spool that operates my loader (boom) is moving. I can check to see if I have cable operated controls if told what to look for. I can call the dealer to ask tomorrow as well. I did confirm there was a strong steady flow on each arm cylinder on the loader. By swapping the loader connections the loader or boom will lift. I looked up the function of the spool and now see why you would question the "travel". I just do not know how to check the spool travel, much less even where it is.

 

[Cesky]

Let me double check this - you placed the valve in float and you cannot raise the loader using a floor jack?

If so your loader is being held down by something and you need to start eliminating possibilities. It could be hydraulic or mechanical. I would suggest you try what I suggested earlier - disconnect the return lines from the loader cylinders and see what that gets you. You could also try unpinning one end of the lift cylinders and trying the jack again.

Dan

Correct, I have done exactly that. Float position and tried to lift with a floor jack. Subsequently I have been able operate the loader up/down by swapping the loader hydraulic connections. This seems a contradiction but that is what happened. I will this again though.

 

[TheOldHokie]

Correct, I have done exactly that. Float position and tried to lift with a floor jack. Subsequently I have been able operate the loader up/down by swapping the loader hydraulic connections. This seems a contradiction but that is what happened. I will this again though.

It sounds like the return line is blocked. Disconnect the rod end hose at the coupler on the valve and I bet the loader raises.

Dan

 

[North Idaho Wolfman]

I'll second what whitetiger said, it's a quick disconnect coupler issue on the valve side!

 

[Cesky]

You have a failed coupler on the valve, either the Raise or Lower coupler will exhibit the symptoms you have.

You can either get one new tip and replace either one on the valve and try it. If that made no difference, replace the other one with the couple you removed and try it. Or you can get 2 new couplers and replace both of the boom Raise and lower couplers at one time.

Dispose of the failed coupler so later someone does not try to use it.

Thank you for the advise. Sorry, if my follow up questions will be too basic.

The loader has four quick disconnect couplers on the tractor right hand side. These are color coded Wh, Bl, Rd, Yl for ports A-D. These are the connections I have been swapping around.

Are you referring to these couplers when you mention "failed coupler on the valve" If so then the "raise and lower coupler" you mentioned would be White or port A, and Yellow or port B. If I am mistaken then please direct me to the proper location for the possible failed coupler.

Again I apologize for what must seem a simple question but what to you mean by replacing "a new tip"
Is this tip the same as the coupler. You also mention replacing this tip on the valve so I am not sure I am focusing in the right location for these couplers.

Doing my best to figure this out. I appreciate your time and advise.

 

[TheOldHokie]

Thank you for the advise. Sorry, if my follow up questions will be too basic.

The loader has four quick disconnect couplers on the tractor right hand side. These are color coded Wh, Bl, Rd, Yl for ports A-D. These are the connections I have been swapping around.

Are you referring to these couplers when you mention "failed coupler on the valve" If so then the "raise and lower coupler" you mentioned would be White or port A, and Yellow or port B. If I am mistaken then please direct me to the proper location for the possible failed coupler.

Again I apologize for what must seem a simple question but what to you mean by replacing "a new tip"
Is this tip the same as the coupler. You also mention replacing this tip on the valve so I am not sure I am focusing in the right location for these couplers.

Doing my best to figure this out. I appreciate your time and advise.

You have four female couplers on the four hoses coming from the loader. There are four matching male tips on the bulkhead bracket attached to the tractor. Its likely the coupler connected to the rod end of the lift cylinders has failed and is blocking the return flow from the cylinder. I can't tell you which coupler that is but it is easy to determine. Go to the ROD end of the lift cylinder closest to the bulkhead connectors and follow that line back to the female coupler. This is the suspect coupler pair. Once again I will suggest you disconnect that female coupler from the hose coming from the loader, put the hose in a bucket, and attempt to raise the loader. If it raises it is very likely the coupler is not opening when the two halves are connected. You can either replace both halves of the coupler or attempt to determine which pieces have failed and just replace them.

Dan

 

[Cesky]

Correct as stated by member posts, my problem was a failed coupler on the bulkhead bracket. Of the four couplers it was the white or port A, male tip. Thank you all for your help and patience as I muddled my way the trouble shooting terminology.