Kubota B7100 hydraulics

[hillbilly56]

Can anyone help? I have a b7100 kubota that I purchased about 6 months ago. The 3 point worked great when purchased but now only lifts at a very low idle. Any throttle at all and it just bounces about an inch. I've changed oil in transmission and cleaned the very dirty filter in the pump inlet line with no change. The decal at the fill cap says 80 wt. oil so that's what I used. Could the oil be too heavy? Any help would be greatly appreciated.

 

[deerseeker001]

Welcome from Wisconsin

 

[Baby Grand]

Welcome, fellow old orange owner.

My B5100 3pt behaves very similar to what you have described.
80W is what my owner's manual calls for, so you're good there.
My hitch is very sensitive to how far open the valve is, especially with significant weight on it.

Try this:
With engine revs at operating speed and the tractor parked, wrap the thumb of your right hand tightly around the handle on the fender to steady your hand.
Using a finger or two of the same right hand, slowly move the lift lever and see if that helps.
If it does, try it again; this time with the tractor in gear and moving.
Works for me - doesn't fix it, but greatly reduces the jerkiness.

 

[hillbilly56]

Thanks for the welcome. I tried slowly moving the control lever but it doesn't seem to work on this one. I'm reasonably sure there's something going on in the control valves. What has me baffled is it worked great until it got cold. Any thoughts appreciated.

 

[Thomas]

Not sure of the year B7100..you may want to check inline strainers,

 

[KubotaSam]

My B7100 manual said to run 80 weight like you said. I asked a dealer about this, they said to run a tractor hydro/trans oil. The told me the 80 was to thick to run here in Maine where it gets cold. If you have checked strainer I think you are correct and the oil is to thick. You also could have a crack or leak in the pump suction line letting air in causing cavitation.