B26 /w BT820 backhoe stuck spool valve

[stealth71]

Recently picked up a used B26. I have used the backhoe a couple times and today while lifting the stabilizers one valve got stuck. I looked at the parts diagram but am not very familiar with hydraulics. What should I take apart to start inspecting ? The valve is currently stuck down and won’t pop back up to center. I have a WSM and see how to take the valve apart but there isn’t much detail. I am hoping I can try to fix it on the backhoe and not have to disassemble the entire valve body.

I see the o-ring and wiper 360 and 370 are those the same part at the bottom of the valve. 340 is an assembly that is over $1k. Hoping I can just replace some small parts.

 

[TheOldHokie]

Recently picked up a used B26. I have used the backhoe a couple times and today while lifting the stabilizers one valve got stuck. I looked at the parts diagram but am not very familiar with hydraulics. What should I take apart to start inspecting ? The valve is currently stuck down and won’t pop back up to center. I have a WSM and see how to take the valve apart but there isn’t much detail. I am hoping I can try to fix it on the backhoe and not have to disassemble the entire valve body.

I see the o-ring and wiper 360 and 370 are those the same part at the bottom of the valve. 340 is an assembly that is over $1k. Hoping I can just replace some small parts.

The spring return mechanism on the end of the spool may be the culprit. They tend to corrode and stick and occasionally the spring breaks. Bottom line is you have to remove the end cover (#14 in your top diagram) on the spool that is stuck to inspect and renew as needed. Getting to it with the valve on the machine is the hard part.

Dan

 

[stealth71]

I sprayed some penetrating oil on the top and wiggled it a bunch and it came free. Not sure if the penetrating oil is just coincidental. It jammed up again and wiggling got it loose. Compared to the other stabilizer valve it seems harder to move. I think something inside might be hanging up. There is not a lot of debris on them. These valves do look cleaner than the others so I’m not sure if someone has taken this apart before. It is suspect as one bolt is missing from the cover.

 

[GreensvilleJay]

Are all the 'joints' between the lever and the actual valve 'free and easy' ? Any 'binding' there could make the valve hard to operate.
Real bummer if it's inside the valve though it looks like you can access the return spring from the bottom ? Still doesn't look like 'fun'..cramped space, stuff in the way, easy for screws to go 'walkabout'.....

 

[TheOldHokie]

I sprayed some penetrating oil on the top and wiggled it a bunch and it came free. Not sure if the penetrating oil is just coincidental. It jammed up again and wiggling got it loose. Compared to the other stabilizer valve it seems harder to move. I think something inside might be hanging up. There is not a lot of debris on them. These valves do look cleaner than the others so I’m not sure if someone has taken this apart before. It is suspect as one bolt is missing from the cover.

End seals on the spool prevent your oil getting inside. Some of the valves have a weep hole in the cap, might be able to get a mist in that way. The spool is a sub thousandths clearance fit in the body. If that is hanging up not much you can do about it. Linkage and return spring problems have a much better prognosis.

Dan

 

[stealth71]

End seals on the spool prevent your oil getting inside. Some of the valves have a weep hole in the cap, might be able to get a mist in that way. The spool is a sub thousandths clearance fit in the body. If that is hanging up not much you can do about it. Linkage and return spring problems have a much better prognosis.

Dan

Roger. Thanks for the input. I appreciate the quick responses and sharing of knowledge as I am new to this machine.

I figured the penetrating oil did nothing, but saw someone mention it elsewhere so I gave it a squirt. I hadn't run it again as I shut if off last night after the valve got stuck. Now that the valve is moving I started it up and it seems to be working again. It does feel slightly different than the other valve. The linkages all look good. Considering the price of the parts I will pull the lower cap to inspect. I was thinking about adding the hydraulic thumb kit which I will start another thread on. Looks like that might require pulling the entire control valve to install the additional thumb spool so I can possibly inspect it closer then.

 

[TheOldHokie]

Roger. Thanks for the input. I appreciate the quick responses and sharing of knowledge as I am new to this machine.

I figured the penetrating oil did nothing, but saw someone mention it elsewhere so I gave it a squirt. I hadn't run it again as I shut if off last night after the valve got stuck. Now that the valve is moving I started it up and it seems to be working again. It does feel slightly different than the other valve. The linkages all look good. Considering the price of the parts I will pull the lower cap to inspect. I was thinking about adding the hydraulic thumb kit which I will start another thread on. Looks like that might require pulling the entire control valve to install the additional thumb spool so I can possibly inspect it closer then.

You can easily add a separate electric (or manual) valve for a thumb. Think loader third function.

Dan

 

[fried1765]

Roger. Thanks for the input. I appreciate the quick responses and sharing of knowledge as I am new to this machine.

I figured the penetrating oil did nothing, but saw someone mention it elsewhere so I gave it a squirt. I hadn't run it again as I shut if off last night after the valve got stuck. Now that the valve is moving I started it up and it seems to be working again. It does feel slightly different than the other valve. The linkages all look good. Considering the price of the parts I will pull the lower cap to inspect. I was thinking about adding the hydraulic thumb kit which I will start another thread on. Looks like that might require pulling the entire control valve to install the additional thumb spool so I can possibly inspect it closer then.

If you are just.... "thinking about adding the hydraulic thumb kit",..... you are probably over thinking it.
A hydraulic thumb is a wonderful thing.
DO IT.... now!
You will then marvel at what a wonderful upgrade it really is!

 

[stealth71]

You can easily add a separate electric (or manual) valve for a thumb. Think loader third function.

Dan

I have been looking at the Kubota parts as it is an option for the B26.
BTB405 - Backhoe auxiliary hydraulic kit
BT1975 - Hydraulic thumb kit

If you are just.... "thinking about adding the hydraulic thumb kit",..... you are probably over thinking it.
A hydraulic thumb is a wonderful thing.
DO IT.... now!
You will then marvel at what a wonderful upgrade it really is!

Good to know. Seems like everyone that has one loves it. I know the parts aren't getting any cheaper. Might as well get them this year instead of next.

 

[Smokeydog]

My first thumb was on a B26. Unbelievable how useful. M59 has one too. Wouldn’t buy a backhoe or excavator without one.