Loader valve problem

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
Hi all. Need a few ideas on a problem we have.
We have a 2012 Kubota B2620. The other day while using it the bucket " down " curl would not function all of a sudden. It would up curl raise and lower . I was lifting a rear blade with it via a chain and the chain slipped and shock loaded the bucket. Not sure that had anything to do with it but the down curl stopped working. I have traced it down to the curl spool not moving in the valve body. Releasing all pressure and removing the cap and spring assembly on the bottom of the spool the spool itself will not come out of the valve body from the top or the bottom.
Prior to getting this far we checked all the loader fitting and they were tight and secure. We also raised and lowered the rear 3 point to different positions and tried it still nothing. there is spring pressure both ways on the spool but it did not travel to the curl down position as far as the up position.
I am stymied as to why the spool will not come out. I have not removed the valve assembly from the tractor yet, been working on it on the tractor.
I will be removing the valve assembly this evening and looking at it. Any suggestions on what might make this happen would be greatly appreciated. Not in a position at this time to shell out a $ 1000.00 for a new valve.
Thanks in advance.
 

TheOldHokie

Well-known member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
2,276
961
113
Myersville, MD
Hi all. Need a few ideas on a problem we have.
We have a 2012 Kubota B2620. The other day while using it the bucket " down " curl would not function all of a sudden. It would up curl raise and lower . I was lifting a rear blade with it via a chain and the chain slipped and shock loaded the bucket. Not sure that had anything to do with it but the down curl stopped working. I have traced it down to the curl spool not moving in the valve body. Releasing all pressure and removing the cap and spring assembly on the bottom of the spool the spool itself will not come out of the valve body from the top or the bottom.
Prior to getting this far we checked all the loader fitting and they were tight and secure. We also raised and lowered the rear 3 point to different positions and tried it still nothing. there is spring pressure both ways on the spool but it did not travel to the curl down position as far as the up position.
I am stymied as to why the spool will not come out. I have not removed the valve assembly from the tractor yet, been working on it on the tractor.
I will be removing the valve assembly this evening and looking at it. Any suggestions on what might make this happen would be greatly appreciated. Not in a position at this time to shell out a $ 1000.00 for a new valve.
Thanks in advance.
Is the spool shifting into the dump position. Many of these valves have a fourth postion on dump with a detent between them.

I would not be in a rush to remove a spool from any valve.

Dan
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
Is the spool shifting into the dump position. Many of these valves have a fourth postion on dump with a detent between them.

I would not be in a rush to remove a spool from any valve.

Dan
No that is the problem we are having it will not dump.
 

TheOldHokie

Well-known member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
2,276
961
113
Myersville, MD
Sorry, yes minimally. If I push it by hand it will go down on spring tension but the bucket will not curl.
If the spool moves the cylinder should respond. I would suggest removing the connections to the work ports - e.g. leave them open - to see if that changes the way the spool acts. Dont operate the valve with the tractor running or you will have an oily mess.

You can also remove the couplers on the bucket lines and see if the bucket moves freely with the lines open.

Dan
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
If the spool moves the cylinder should respond. I would suggest removing the connections to the work ports - e.g. leave them open - to see if that changes the way the spool acts. Dont operate the valve with the tractor running or you will have an oily mess.

You can also remove the couplers on the bucket lines and see if the bucket moves freely with the lines open.

Dan
Thanks. I will try that tomorrow.
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
Thanks. I will try that tomorrow.
Checked all coupling again and they were good. Switched out lines and it operates in reverse with lines switched. but will not operate the dump function now.
I believe that there is something wrong with the 2nd position dump detent on the loader valve. Still checking but it is getting frustrating. Looking into it further today , much cooler and less humid today at 72* F. Thanks for the help.
 

TheOldHokie

Well-known member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
2,276
961
113
Myersville, MD
Checked all coupling again and they were good. Switched out lines and it operates in reverse with lines switched. but will not operate the dump function now.
I believe that there is something wrong with the 2nd position dump detent on the loader valve. Still checking but it is getting frustrating. Looking into it further today , much cooler and less humid today at 72* F. Thanks for the help.
Not clear what you did but it seems the spool is not stuck. If you have regen on the dump circuit. you cannot reverse the hose connections to the cylinders. If you do the cylinder will retract in both positions.

Dan
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
Not clear what you did but it seems the spool is not stuck. If you have regen on the dump circuit. you cannot reverse the hose connections to the cylinders. If you do the cylinder will retract in both positions.

Dan
Currently it will not dump ! It is like the spool is stuck in the valve body. The spool will move just a little bit in the dump direction but the bucket does not work when I put it back together . It says it has regen on the dump but I do not ever remember using it. I just got done bolting everything back together at the loader valve and tried it again. Bucket is curled up as far as it will curl and will not dump! The bucket does raise and lower as well go into the float condition. I'm at a loss.
 

GreensvilleJay

Well-known member

Equipment
BX23-S
Apr 2, 2019
4,657
1,476
113
Greensville,Ontario,Canada
Ok silly question, but...
does the lever move the spool the same 'range' as before ? fully back, fully forward
does it feel 'normal' ?
is the lever -linkages- valve all mechanically connected as before ?
is there any 'friction' compared to 'before the booboo' ?

just trying to eliminate some oddball failure that magically happened at the same time....
 
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TheOldHokie

Well-known member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
2,276
961
113
Myersville, MD
Currently it will not dump ! It is like the spool is stuck in the valve body. The spool will move just a little bit in the dump direction but the bucket does not work when I put it back together . It says it has regen on the dump but I do not ever remember using it. I just got done bolting everything back together at the loader valve and tried it again. Bucket is curled up as far as it will curl and will not dump! The bucket does raise and lower as well go into the float condition. I'm at a loss.
Very odd that a spool would fail like that. Do you still have the lines reversed on the bucket cylinders?

Dan
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
Ok silly question, but...
does the lever move the spool the same 'range' as before ? fully back, fully forward
does it feel 'normal' ?
is the lever -linkages- valve all mechanically connected as before ?
is there any 'friction' compared to 'before the booboo' ?

just trying to eliminate some oddball failure that magically happened at the same time....
All linkage is connected and free I even lubed it lightly when I put it back together. Up and down has the range of motion it has always had. The curl up functions as it should. The curl down has motion but it does not seem as far as before it stopped working.
When we had this torn down to where we could actuate the spool it appears to stop like it is hitting something solid. We removed the cap on the spool and took the bottom off and it should of came out the bottom or top and it will not come out. I called local dealer service tech and he said the spool should come out freely. This is the spool that has the regen detent and I was wondering if something had moved to stop it from moving. Thanks.
 

TheOldHokie

Well-known member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
2,276
961
113
Myersville, MD
All linkage is connected and free I even lubed it lightly when I put it back together. Up and down has the range of motion it has always had. The curl up functions as it should. The curl down has motion but it does not seem as far as before it stopped working.
When we had this torn down to where we could actuate the spool it appears to stop like it is hitting something solid. We removed the cap on the spool and took the bottom off and it should of came out the bottom or top and it will not come out. I called local dealer service tech and he said the spool should come out freely. This is the spool that has the regen detent and I was wondering if something had moved to stop it from moving. Thanks.
Sounds like its time to take the valve to a professional.

Dan
 
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comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
We have decided to remove the valve body and check it out. I will be laying a old sheet between the tractor fender and on the floor below just in case when I remove the lines something comes out or falls out. More later and pictures if I can get them to post.
 

torch

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Equipment
B7100HSD, B2789, B2550, B4672, RC54-71B, 48" cultivator, homemade FEL and Cab
Jun 10, 2016
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83
Muskoka, Ont.
I was lifting a rear blade with it via a chain and the chain slipped and shock loaded the bucket. Not sure that had anything to do with it but the down curl stopped working. I have traced it down to the curl spool not moving in the valve body.
It was working before, then the shock loading, now it doesn't work?

Pretty good bet that the shock was transmitted through the system and broke something. Or shook something loose. Could be as simple as a bit of rubber o-ring jammed where it doesn't belong. I would definitely either take it to a shop or disassemble it.
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
It was working before, then the shock loading, now it doesn't work?

Pretty good bet that the shock was transmitted through the system and broke something. Or shook something loose. Could be as simple as a bit of rubber o-ring jammed where it doesn't belong. I would definitely either take it to a shop or disassemble it.
This is what we found. Looks like the shock caused the relief valve to fracture! Galled the spool also. Valve body looks good.
20220624_135349.jpg
 

comforthill

Member

Equipment
B2620,back blade,mower,tiller,loader,middlebuster,landscape rake
Oct 14, 2018
46
0
6
Lewiston
I hope that spool is still usable.

Dan
Well, the relief valve is $ 920 00 ! Just the two relief valves. I called several places to price it !! Looks like a new valve for 200 more. Just my luck. Thanks guys. Appreciate the help.