Bucket "sticking" when dumping (newer tractor)

[braccet]

I have a new Kioti with only 60 hours on it. Been doing a lot of dirt moving on our new property. I noticed when the bucket is full and I am dumping into a pile, the bucket will "stick" at about the last 10% of travel on its way towards the full dump position. Takes a second or two to get through this spot. Curiously right after the dump if I exercise the bucket up and down it doesn't stick.

I just did the 50 hour service a few weeks ago, so hydraulic fluid and filter is new, and I checked the level and it's full. Bucket cylinders don't appear to be bent to the naked eye, but I'll check with a straight edge. I last greased the loader about 10 hours ago but will grease it again next time I'm there.

Any other ideas on things to check?

 

[JCoastie]

are you dumping fast at a lower engine RPM?
Keep those RPMs up
It might happen when full because the weight of the dirt causes the bucket to dump faster than the hydraulic system is pumping oil to the cylinders causing an air pocket and takes a few seconds to catch up.

 

[MapleLeafFarmer]

also take the bucket off and check the timing of the mounting pads of the quick attach system. Let us know if they got "tweaked" and are out of sync which might cause binding at certain angle point/

 

[5030]

When was the last time you greased the pivot pins? The loader should be greased every 10 hours at the minimum. Have you evert greased it? If not, it could be 'hanging' on dry pivots.

 

[5030]

On my open station M9' the parallel linkage to the bucket is worn out, consequently, I have a 'floppy bucket' but not because of fluid flow but because the linkage is worn out (which won't apply to a new unit), but will apply if you don't keep it lubricated. I'm about to cut and weld up new linkage parts on my CNC plasma table and replace them in as much as Kubota wants a stupid price for new ones. like 500 bucks a set of 2 x 4 sets. I can cut and weld them for about 1/10th the cost.

 

[Bavarian]

are you dumping fast at a lower engine RPM?
Keep those RPMs up
It might happen when full because the weight of the dirt causes the bucket to dump faster than the hydraulic system is pumping oil to the cylinders causing an air pocket and takes a few seconds to catch up.

The wording "air pocket" is not quite right. It's vacuum.
The rest of your statement is head on.

The hydraulic system is sealed. There is no way air could get into the system except there is a leak on the suction side of the pump or the fluid is low in the reservoir.

To lessen or solve the problem, there are adjustable flow valves with free return flow available. Install them into the curl up line and restrict the flow that is caused by the weight of the load in the bucket does help with that problem.
That is not new or tractor specific only. Even excavators suffered that problem up to about 40 years ago. They had flow restrictions installed in the lines.
Later on it got solved internally in the hydraulics itself.

 

[kennyd]

I bet you are putting the joystick in the 'regen' or regenerative position.

Good reads here:

Search results for query: regen

www.tractorbynet.com

 

[braccet]

Thanks for all the help. Didn't know there was a term for this (floppy buckey syndrome). The inability of the pump to keep up when a heavy load is moving the bucket by gravity is likely the culprit.

I'm keeping RPMs around 2300 (about where the non-eco PTO speed indicator is). The engine max is 2600. Can/should I peg it when doing loader work? Thought I was saving a little gas but if it won't do hard to put it at 2600 I can try it.

I do grease every 10 hours and paid extra attention today before working to make sure grease was coming out of every pin.

 

[JCoastie]

RPM sounds fine, just try dumping a little slower, don't need to be slow, just not max dump speed.