Leak Down

[Tractor_Mike]

I have a Kubota B7100 hyd with a Kubota front end loader. The bucket slowly tilts down on it's own and must be tilted back with the joystick. The problem has been getting worse and if I have a big load it must be tilted back every minute or two. I tried replacing the seals in the cylinders but didn't help. There is no sign of oil leaking anywhere. Any suggestions? Mike

PS The arms stay where I put them, only the bucket tilts down.

 

[Henro]

Sounds like the control valve for bucket curl is leaking through.

You might try swapping hose pairs at the control valves just for a test to see if the symptom moves from the bucket to the lift arm function.

Just a thought... /forums/images/graemlins/smile.gif

 

[Tractor_Mike]

Sounds like an exellent idea, thanks. Mike

 

[Bird]

How old is that B7100? I bought a new one in 1995 and it would do that. The dealer replaced the seals in the cylinders; no help. The dealer kind of gave up and tried to tell me it was normal, but when I contacted Kubota and they sent a factory rep to my house to see it, he thought it was leaking back through the valve. They checked that and found the valve was OK; it was the cylinders. So they replaced all four cylinders on mine under warranty and that fixed it.

 

[Tractor_Mike]

I bought mine new, between '92 and '94. I had this problem even when it was new, but it would be all night before the bucket would tip enough for a load to spill, now it only takes a few minutes. I havn't had a chance to switch lines yet but after I do I'll post a reply. Mike

PS It's been a great tractor, just right size for me. I use a 48" tiller, a 12" auger, a 60" box blade, a 72" landscape rake, fertilizer spreader and seeder, 48" bush hog, plow and of course the front end loader. This tractor has seen a number of wide open 8 hour days with a tiller in the pumpkin fields. I've got around 1000 hours on it now and this is the only problem I've ever had.

 

[Bird]

I gather from this thread that your problem is only the bucket curl, whereas my bucket tilted forward (dumped) gradually and the boom also slowly lowered. So my problem was all four cylinders. I think Henro's suggestion will tell you whether it's the cylinders or the valve. If it is the cylinders, new seals may fix it. New seals did not fix mine, but I think they decided that the interior of the cylinder walls had been scored during manufacture or assembly. So if yours has not been doing it until lately, then it probably is just the seals (or of course the valve).