BH90 Stiff Hydraulics

[craiglandrum]

I've used my BH90 now for over 200 hours and never had a problem. Recently, while digging a stump I managed to break one of the short rods that link the right hand joystick to one of the hydraulic valves that it controls. After replacing the small rod (using a Kubota part), the joystick was very stiff and some hydraulic fluid begand leaking from underneath the control box. The tractor needed its 200 hour maintenance so I had them do the 200 hour and also fix the backhoe hydraulic leak at the same time. When the tractor came back the leak was fixed but the joystick remains very stiff and I have to exert undo pressure all the way to the stops to get the bucket to move. I suspect that there is some magic adjustments that are needed to the linkage or valves that I am unaware of. I haven't been able to locate a BH90 service manual online (link would be appreciated) which I would expect to cover any adjustments needed. Anyone have a clue what is wrong or how I might begin to fix this? Would rather not have to get it trailer back in to the dealer, etc.

FYI, the BH90 is attached to my L3830 with a 723 loader.

 

[kennyd]

Welcome to TBN

Have you tried spraying all of the linkages on the valve body with PB Blaster or WD-40?

 

[craiglandrum]

Did that, no effect. I really believe it is some type of adjustment problem - if I fool around with loosening/adjusting the linkage nuts, I can get one axis or another working smoothly, but not both together. I wonder if there are other adjustments I could make - the bottom of the control unit looks promising but I'm not going to touch that unless I either have a manual or someone experienced on this list tells me how to do the adjustment. Wish I could find an online source for the service manual....

 

[dfkrug]

Did that, no effect. I really believe it is some type of adjustment problem - if I fool around with loosening/adjusting the linkage nuts, I can get one axis or another working smoothly, but not both together. I wonder if there are other adjustments I could make - the bottom of the control unit looks promising but I'm not going to touch that unless I either have a manual or someone experienced on this list tells me how to do the adjustment. Wish I could find an online source for the service manual....

When using a joystick and its linkages to control 2 valves, I have had
to adjust the linkages with small washers (shims) to get the alignment
just right. Yours went out of alignment when you changed a link, IMO. If
you totally remove the bolts holding the joystick to the valves, you
will prob see a washer at one or more locations. Add or remove
washers for each axis of movement to get the right alignment. The shims
are not on the linkages themselves, they are underneath the support plate,
at least on the valves I have adjusted. Yours may also have adjustable
links, using a threaded rod.

I have seen a newer BH75 exhibit the same behavior due to lack of lube
for the swivel eyes. Use oil, not WD40 if you want the lubrication to last.