hydraulics half working after changing bucket for snowblower

[Famah Dave]

I swapped out the bucket on my Kubota B2920 HSD tractor for the snowblower, tis the season and all. The bucket was working fine including the bucket tilt which now drives the snowblower chute rotation. I have rotation in only one direction. The engine strains pumping pressure the same in either direction. When I swap the hoses at the rotation motor I get rotation in only the other direction, so motor and gear mechanism seems ok and isn't bound up. When I check flow out of the hoses at the motor I get flow out one as expected when driving in the working direction but flow out of both when trying in the non working direction. I assume both hoses are clear since flow is out one and back the other in the working direction. Filters were changed on schedule and should be ok, oil is full to the top line. I have a pressure gauge kit arriving Saturday and snow coming tomorrow. I'll manage by getting off and manually turning the chute as needed but figured I'd try asking here if anyone knows what the likely problem is or some other tests to help diagnose the problem, I'm stumped and hope getting pressure readings will help.

thanks,
Dave

 

[Dave_eng]

I swapped out the bucket on my Kubota B2920 HSD tractor for the snowblower, tis the season and all. The bucket was working fine including the bucket tilt which now drives the snowblower chute rotation. I have rotation in only one direction. The engine strains pumping pressure the same in either direction. When I swap the hoses at the rotation motor I get rotation in only the other direction, so motor and gear mechanism seems ok and isn't bound up. When I check flow out of the hoses at the motor I get flow out one as expected when driving in the working direction but flow out of both when trying in the non working direction. I assume both hoses are clear since flow is out one and back the other in the working direction. Filters were changed on schedule and should be ok, oil is full to the top line. I have a pressure gauge kit arriving Saturday and snow coming tomorrow. I'll manage by getting off and manually turning the chute as needed but figured I'd try asking here if anyone knows what the likely problem is or some other tests to help diagnose the problem, I'm stumped and hope getting pressure readings will help.

thanks,
Dave

A bit more history might help with advice.

Has this arrangement worked in previous years or is this the first year.

Does your loader valve have two dump positions, one position being a REGEN dump or fast dump?

Can you easily swap connections to try the loader arm circuit on the chute motor?

Dave

 

[200mph]

Push the joystick far right past the detent to get it rotated to right. This is past were normal bucket operation is and if the detent might be somewhat stuck requiring additional force to do so the first time. It may also seem awkward to push it this far right. (This assumes your loader valve has this position).

This is a common question when the snow starts to fly the first time.

Good luck and report back what you find.

 

[Bmyers]

GP Outdoors talks about that issue here in this video

Got to go past the detent as 200mph pointed out

 

[Famah Dave]

A bit more history might help with advice.

Has this arrangement worked in previous years or is this the first year.

Does your loader valve have two dump positions, one position being a REGEN dump or fast dump?

Can you easily swap connections to try the loader arm circuit on the chute motor?

Dave

Yes, glad to give more info. This is my fourth year with the snowblower without issues. It is a kubota BX5455HD blower with B2733A quick hitch and sub-frame (for blowers, plows and other front mounted attachments) that then attaches to a permanent frame bracket that I had the dealer install when I bought the snowblower. The tractor I bought barely used with about 750 hr. and got the blower new the first year. I have to remove the LA364 loader (bucket and lift arms) completely to mount the blower on front. So not real easy to switch back for a test.
The loader control has a single lever going to the value block so you can control both simultaneously. Forward and back is main loader arm lift cylinders which in the case of the blower also raises it using a single cylinder. Left/right on the lever is the bucket up and down (scoop/dump) cylinders and the chute on the blower left and right rotation via a simple hydraulic motor.
Both actions are under pressure in both directions, I can lower the arms or bucket and lift the front end of the tractor off the ground. The loader arm/blower raise lower control does have a (full forward) position that lets it float. The bucket does have any float or fast dump or extra control action. I haven't pulled the control valve out yet, but it is mechanically connected (no solenoids) to the lever and seems to be working fine lifting/pushing the valve spool rods. As I mentioned when I try to rotate the chute in the non working direction I can hear the engine getting loaded just as in the working direction so the valve seems to be switching in both directions.
The chute has limit stops but if I take it off I can run the motor and gear continuously in the working direction so the other hose must be clear for return flow. And as I mentioned if I swap the hoses at the motor it runs in the oppose direction fine too but still not in reverse.
I'm stumped, the loader bucket was working fine right up until I took it off. I then mounted the snowblower and tested both the raise hydraulic circuit so I could move it and the actual blower function that runs off the mid PTO on a long shaft to make sure all was locked in place but of course didn't try the chute rotation until it snowed and I needed it. Luckily the motor isn't so tight that I can't rotate the chute by hand because its snowing again today and just came back in after using it.

thanks,
Dave

 

[Famah Dave]

GP Outdoors talks about that issue here in this video

Got to go past the detent as 200mph pointed out

OOOH nice, thanks, but mine doesn't have the chute curl function, just rotate and I don't have the float or extra indent on the bucket or chute rotate control just on the loader arm or snowblower lift/drop action so it can follow the ground. I also have to admit I broke the lever off its bolt block trying to push even harder to make it turn and had to weld it back on, so if I did have a detent, I was pushing way past it.

But now I'm jealous the chute curl is ok, I mostly leave mine full up for long throw but my scraper blade is manual and I have to get off to turn it. Hydraulic control of that would be very handy.

 

[kubotasam]

If the rotation has worked in previous years you must have the 4 position dump as 200mph said in post #3. If it will not rotate the chute something has gone wrong in the control valve.

 

[Famah Dave]

Push the joystick far right past the detent to get it rotated to right. This is past were normal bucket operation is and if the detent might be somewhat stuck requiring additional force to do so the first time. It may also seem awkward to push it this far right. (This assumes your loader valve has this position).

This is a common question when the snow starts to fly the first time.

Good luck and report back what you find.

I did check the manual and I do have the two stage dump valve, guess I never seemed to use or notice it when working the loader. It is true that its the right direction that doesn't work, but as I mentioned I did push the lever to the right extra hard trying to get it to turn. Sufficiently hard in fact to crack the weld holding the lever to the plate that bolts it onto the valve control and had to re-weld it. So this doesn't seem to be my problem. I'd taken the lever off to weld and did my testing without it using vice grips to move the valve rocker.
I do have to assume something is wrong with the valve, with oil flowing out both hoses when trying to turn right, something is leaking. Why the problem only shows up on the snowblower and not the loader is a mystery. I know I had enough down pressure on the bucket to lift the loader arms out of its pivot sockets to remove it before mounting the blower. My pressure gage kit should arrive saturday and I can then test the pressure.

I'll report what I eventually find out.

 

[Famah Dave]

If the rotation has worked in previous years you must have the 4 position dump as 200mph said in post #3. If it will not rotate the chute something has gone wrong in the control valve.

Yes I check the manual and I do have the 4 position value, I just never noticed using the bucket, I must always go to the normal position and haven't tried stopping for the fast dump. Something to try come spring.
But I did try pushing extra hard to get the chute to swivel, hard enough in fact to break the weld holding the lever to the value. I'd re-welded it and pushed hard again, no movement. I have to assume a faulty value, but why only now when I switched to snowblower?
I'll report what I find when I finally get it fixed. Pressure gauge coming Saturday.

 

[Famah Dave]

A bit more history might help with advice.

Has this arrangement worked in previous years or is this the first year.

Does your loader valve have two dump positions, one position being a REGEN dump or fast dump?

Can you easily swap connections to try the loader arm circuit on the chute motor?

Dave

Just realized what you meant, switching arm control and bucket or blower lift and chute rotate. Great idea, I'll have to try that just to see. Duh, I thought you meant to switch back to the loader.

 

[kubotasam]

I do have to assume something is wrong with the valve, with oil flowing out both hoses when trying to turn right, something is leaking. Why the problem only shows up on the snowblower and not the loader is a mystery. I know I had enough down pressure on the bucket to lift the loader arms out of its pivot sockets to remove it before mounting the blower.

Oil flowing out both hoses is what is is supposed to do in the regenerative dump position. When people are telling you to push to the right a little more it is to get the spool in the valve to the position where fluid only comes out one of the hoses. Like the up and down spool does. The valve is not leaking. Something is stopping the spool from moving far enough to go past the regenerative dump position.