Loader Bucket direction reversing when high flow option selected

Mustache · Jul 25, 2014

Not sure if the title of this thread makes sense, but I'll try to explain.

I have a Massey Ferguson 1560 with Front End Loader.

The other day when bush hogging a part of our property, I worked the loader while driving and mowing and when selecting the rapid dump the bucket all of a sudden tilted in, instead of dumping. Rapid dump as in lifting the boom and dumping the bucket at the same time. The valve is supposed to supply more oil/pressure to the bucket to dump while the boom still lifts. The loader has joystick control.

Just to clarify this some more, if I just select bucket dump (joystick to the right) it dumps, once I push further right (to the dump bucket and lift/lower boom simultaneously) the bucket suddenly reverses direction from dump (as it should be) to curl in.

After investigating some more, I found out that I don't have down pressure on the bucket either, but it can hold loads at the same time. The boom works fine, its just the bucket.

Last night I took the valve off and suspected maybe a leaky o-ring, but there is really nothing to it. Just a piston that directs the oil flow inside the valve and 3 o-rings between the different valves. Everything looks good.

I have not put it back together, but I am now suspecting it could be one (or both, that's what confuses me) of the bucket cylinders? If I dump the empty bucket, the tractor seems to have to labor quite a bit to get it to dump. The engine RPMs drop quite a bit off. Curling in seems to work just fine.

Any ideas what this might be, anyone?

Thanks,
Chris

ETA: Administrators, please move to Hydraulics forum!

Zebrafive · Jul 25, 2014

The "labor" to dump makes me suspect a quick coupler not correctly coupled/seated, causing a restriction. I assume you have quick couplers connecting the loader.

Crusty49 · Jul 25, 2014

Zebrafive said:
The "labor" to dump makes me suspect a quick coupler not correctly coupled/seated, causing a restriction. I assume you have quick couplers connecting the loader.

I second that. I had the same problem on my 1533 last winter. It looked like it was connected but if you wiggled it a bit you could tell it wasn't right.

Mustache · Jul 30, 2014

So, it is definitely not the Quick Couplers and the valve seems to be fine too.

I checked some more for the down pressure and I have proper pressure at the boom, but the bucket is basically just flopping around under load. It works fine while empty, except for the rapid dump.

LD1 · Jul 30, 2014

Rapid dump simply doesnt add any more pressure or flow. IT is a re-gen circuit. It gives full pressure to both sides of the cylinder. Since the base end of the piston has more surface area, it still extends, and all the fluid on the rod side of the piston flows to the base end making it quicker. But you only have a force that would be equal to a cylinder bore size being the size of the rod.

So, if the valve is working properly in regen (full pressure and flow out both dump and curl ports), but yet the bucket still curls tells me that you arent getting flow/pressure to the base end of the cylinder.

And you said you have no down pressure, (assuming with the curl circuit) which would further confirm you arent getting fluid to the base end of the cylinder. And when you are dumping with a load it is just gravity doing the work.

I would certainly suspect a quick coupler also.

Mustache · Jul 30, 2014

So LD1, what am I looking for then on the Quick Couplers? I do know that one of the male fittings is older as in has more of a pin than a ball fitting. I have to check if that one is for the bucket or the boom though.

I will take the fittings off the hoses tonight and see what I can find.

LD1 · Jul 30, 2014

Pin and ball styles are usually not interchangeable if thats the case.

A female pin will only work with a male pin style. And a female ball style will only work with a male ball style.

But either case, if they are wore out or not properly seated, they just dont work right.

Any more background info? Have you done anything recently? Did you just get the tractor and it came with this problem? or has it been working fine forever and just now acting up without you messing with, changing, or tampering with the hydraulics in any way?

Mustache · Jul 30, 2014

I have the tractor for over a year and put over 200 hours on it. Never had problems with the hydraulics at all. Until last week while bush hogging I moved the loader to dump out accumulated branches and seeds from the tall grass. That's when it all of a sudden reversed the direction. I had not taken off the loader or anything, but had used it regularly to move pallets and lumber with forks until that day.

Again, this problem occurred in the middle of operation. I had dumped the bucket before in the same run and everything went as expected.

Now, come to think of it, I am mowing "new to me" terrain and have the bucket really low to hit rocks or other stuff with the loader instead of the tractor or the bush hog. Also to push down taller brush (8' or 10' tall willows, birch and cherry brush before driving over it to cut it). In one of the runs I "bottomed out" the loader in a pile of dirt. Nothing crazy in my opinion, but I basically pushed the loader into dirt at fairly high speed, enough to stop the tractor. I blew an old and porous bucket hose this way before, maybe it affected the bucket cylinders this way or the quick couplers? Seems kind of unusual to me as I was going maybe 5km/h at most.

LD1 · Jul 30, 2014

could have been enough to unseat a worn out coupler. Or cause internal damage to one of them.

Am I correct in assuming that the bucket wont dump with any kind of power at all? If the loader is FLAT and resting on the ground, will dumping the bucket raise the front of the tractor?

IF not, crack loose a hose from the base end of one of those cylinders, place in a bucket, and move the lever to dump position (not fast dump). And see if flow comes out.

On my tractor, the fast dump (regen) is the first position. All the way over is the "normal" operation of the valve. And its kinda odd that no mention is made of this in my manual or on the sticker that tells what the positions are. The only "extra" position listed is the float mode. But it is definataly 2 positions for dump, and the first is regen. Its faster and even listed as a quicker cycle to dump (extend cylinders) than it is to curl back.

Are you sure one of the dump positions might not be a float?

Either way, do the bucket thing like I mentioned. You need to know if you are getting fluid to the base end of the cylinder.

Mustache · Jul 30, 2014

Thank you LD1.

I think what I will do tonight is check all the couplers, starting with the ones for the bucket and take them apart. So far I had only diconnected and looked a the couplings. They un-seat and seat fine and easy though. Considering there is only one pin-style coupler and all others look new, I will start with that. I have to check if the older coupling belongs to the bucket. If I can't find anything or it doesn't fix the issue, I will try to reverse the hoses for the bucket. See if the problem persists. Then I'll go from there.

The dump position is not a float, that is forward and needs to "pass" an extra "bridge" in the joystick control. I push to the right, also through a "bridge", so I can move the boom and the bucket at the same time.