Did I bust something on the loader hydraulics?

[4570Man]

How could air in the hydraulic system possibly cause the loader to be twisted?

It can’t. A lot of people don’t realize it but the hydraulics on a loader have zero synchronization ability. The loader frame itself is the only thing keeping it aligned.

 

[4570Man]

One thing I’ve noticed on the M59 is when lowering the loader there is a notable load on the engine. This is confirmed by an slight increase in loader lift pressure by gauge.
Given the loader capacity I thought this maybe a hydraulic feature to better control heavy loads by controlling the opening of opposing cylinder valves? This prevents low pressure or vacuum on the lifting side of cylinder.

Don’t know if this is a design feature, adjustable valve function or fluke? Haven’t noticed this on other Kubota tractors to this level.

Seals on hydraulic cylinders and pumps do well of preventing oil loss or leaks under pressure. Do little to prevent air leakage into system if there is internal vacuum.

I think it only behaves that way in self level mode. I never liked the self level on my M59.

 

[Bobrown14]

Was this ever resolved?? I have the same issue with a very similar tractor MT352.

Curl cyliders



Trying to line up the QA



Close up of the QA points each side this is a PITA trying to attach an implement specially a heavy one like a snow pusher. I dont store the implements on flat ground either so getting the QA attach points level is gonna make my work a little more fun.

 

[JCoastie]

picked up the tractor late last week, the dealer got it much closer. Mine was a lift, not curl issue. They said they put the low side of the bucket on a couple blocks, and used the loader to lift the tractor quite a few times, also said they let it sit that way for a bit. It is a lot closer than it was.
I may try it a bit myself, as there is just a little further to go until it's completely level again.

 

[LS Tractor Owner]

When my neighbor first got his LS, while he was unloading off the trailer, I noticed the bucket being 2" lower on one side. We attempted to level it as your dealer did.... maybe a little better, but not level.

The tractor went back to the dealer a few weeks later. The solution was to loosen EVERY bolt holding the loader mounts to the tractor frame. Then allow the loader / bucket to rest level on the shop floor. Then they tightened the bolts back to spec.

WAALAA! Bucket was within 1/4".

 

[JCoastie]

I did loosen all the bolts with the loader resting on the flat garage floor, the tilt remained, I then lifted the tractor front wheels with the bucket and tightened all the bolts with the wheels in the air and bucket on the flat floor. - No change.

 

[JCoastie]

This is what it looks like on a flat surface

Across the lift arms, and the garage floor is level as checked prior with this same level and direction.

Tonight I crawled under it with a creeper, I still see nothing bent. I torqued all the loader bolts. (Tractor was split at the dealership for maintenance just before this happened) found 3 loader bolts that were not torqued to spec, they were more than snug, but not tight. I saw no signs of slipping. Torquing the bolts made no difference.
I loosened the right side loader bolts with the loader slightly off the deck and had my wife stand on the right side of the bucket. It didn't move much (I can bounce it up/down, she can't much), and I re-tightened the bolts. No change.
I loosened the left side bolts and then put a couple boards under the left side of the bucket, put enough pressure to slightly lift the tractor and re-tightened the bolts, there might have been a small amount of positive change.
Tomorrow (or Wednesday, ... have Dr appt tomorrow) I'll loosen both sides, then lift the tractor with the bucket and re-tighten, and see if that makes any difference.
Using my body weight in the bucket, there seems to be more bounce/flex in the right side, though I can't see if the rams are moving from that angle. It does visually seem that there is just flex in the loader arms. It "seems" the left side bounces, and the right side flexes if you can visualize that.
I should also mention, that before all the above, I ran the FEL to the upper limit, and to the lower limit lifting the tractor off the ground 10 times each to ensure any air would have been purged.

This was driving me crazy the last year. I had a tree fall a few weeks ago, and used that as a lever to bend it back, the exact opposite of what happened originally, only on purpose lol It was a little frightening a lot risky, and maybe a little dumb purposely ramming into a tree trunk a few times with a long tree sticking out the grapple, but it seems level/flat again, and it's been holding that way for a few weeks. Had previously tried just using the hydraulics and the bucket under an unmovable object, that didn't have any effect, needed a much larger lever.

 

[DieselBound]

Dealer changed the saddles (rear mounts for loader) on my Kioti to address unlevelness. I cannot recall whether that actually did resolve the issue; I just know that it's out of whack now/still- I just live with it (nothing is level around me anyway; only when doing fork work does it tend to be an issue. I'll note that I did discover that my front brush "guard" isn't level (looking out over the hood and seeing the top of it and the front loader cross bar) and that tends to overstate the unlevelness of the loader itself.

I've pushed my B7800 to insane levels (some would say I was purposely trying to break it- think of EA Ted) and everything on it is still level as can be. If only everything was built like the B7800!

 

[rScotty]

My impression is that front loaders get uneven because metal got bent or tweaked. I can't ever recall it being simply loose bolts, corroded pins, or hydraulics.

Metal stretches when it bends, which is why it can't be bent back.... it can't "unstretch". So it has can be bent somewhere else to compensate. Do that enough & it is certain to find or create a weak spot.

Don't accept a new tractor with an unlevel bucket no matter what they say. And DO NOT pick up things with one corner of the bucket if you want it to stay straight. Trying to get it back to straight again is near impossible. The bend could be anywhere - even back in the frame. Sorry, I wish it was different.

rScotty

 

[JWR]

This was driving me crazy the last year. I had a tree fall a few weeks ago, and used that as a lever to bend it back, the exact opposite of what happened originally, only on purpose lol It was a little frightening a lot risky, and maybe a little dumb purposely ramming into a tree trunk a few times with a long tree sticking out the grapple, but it seems level/flat again, and it's been holding that way for a few weeks. Had previously tried just using the hydraulics and the bucket under an unmovable object, that didn't have any effect, needed a much larger lever.

I think I mentioned last year that my DL250 loader on a MF 2660 is "bent" also. With one edge of the bucket lower than the opposite (left or right) edge. You found you can "reverse the torque" and get yours level with a long lever involved. I was able to get under some immovable object (a large stump) with the high corner and use max force with the loader hydraulic while ramming it with the tractor in low gear and AWD and leveled mine. Seems risky as you say but it works. When you have inspected the daylights out of it for any crackled paint or broken welds and found none I think you just have to conclude that loaders are weak in rotational (torque.) There are no specs on FEL torque, you cannot get ANY info out of the manufacturers -- who simply tell you to avoid torque and unbalanced loads, etc. The national lab for tractor testing in Nebraska does not test FEL torque in part because there are no specs to go by. So you have two choices: go reverse torque it until you get it straight enough to suit yourself or take it to an auto frame shop and pay big bucks and let them do it. Truth is, it is not critical and does not matter much in most applications.

 

[JWR]

My impression is that front loaders get uneven because metal got bent or tweaked. I can't ever recall it being simply loose bolts, corroded pins, or hydraulics.

Metal stretches when it bends, which is why it can't be bent back.... it can't "unstretch". So it has can be bent somewhere else to compensate. Do that enough & it is certain to find or create a weak spot.

Don't accept a new tractor with an unlevel bucket no matter what they say. And DO NOT pick up things with one corner of the bucket if you want it to stay straight. Trying to get it back to straight again is near impossible. The bend could be anywhere - even back in the frame. Sorry, I wish it was different.

rScotty

Scotty I agree with your analysis about 70% but the other 30% is that I think the mounting structures for FELs differ among the many brands and 3rd party manufacturers. Many of them have mounting structures/brackets that have pins resting in notches that are NOT a tight fit laterally -- they sit snug but nothing much holds them left and right. A lot of the "slop" is there simply because all of them are designed for quick removal and or mounting. The net result is that when the loaders get torques there are modes of "taking up clearances" that do not involve bending anything but rather scooting the loader frame around in the mounting slots. A very small difference in "using up all the tolerance" in one direction versus "using up all the slop in the other direction" is tiny at the loader mount but can give 2 or 3 inches of unlevel at the bucket tips. My thinking.

 

[rScotty]

Scotty I agree with your analysis about 70% but the other 30% is that I think the mounting structures for FELs differ among the many brands and 3rd party manufacturers. Many of them have mounting structures/brackets that have pins resting in notches that are NOT a tight fit laterally -- they sit snug but nothing much holds them left and right. A lot of the "slop" is there simply because all of them are designed for quick removal and or mounting. The net result is that when the loaders get torques there are modes of "taking up clearances" that do not involve bending anything but rather scooting the loader frame around in the mounting slots. A very small difference in "using up all the tolerance" in one direction versus "using up all the slop in the other direction" is tiny at the loader mount but can give 2 or 3 inches of unlevel at the bucket tips. My thinking.

I would go with that. There have to be some times where normal mounting clearances and loose fasteners have allowed the clamping to rotate somewhere in the mounting system - and that can certainly cause an uneven bucket. And as you say, it is likely to be all the way back at the farthermost frame mounting.
We know how to loosen and tighten in sequence - it costs nothing and I agree It's worth going after.

I'm guessing that most dealer mechanics know that too - but getting them to do it may be another problen. Best to do it yourself. So loosen all, straighten, and retighten in sequence is the first thing I would try. Particularly with an Add-On loader. Not on a TLB. If it doesn't work, something is bent.

I was just saying that when a loader is out of kilter because of a bend, then a bend always means something stretched. So in fixing it, remember that metal cannot be unstretched. All we can do is to bend it somewhere else to compensate. And doing that necessarily takes more force than the first bend ..... not a road we want to start down.

BTW, I found out the hard way that when optional buckets are offered, get the optional heavier bucket with a bolt-on cutting edge. Usually called a dirt bucket as opposed to a materials bucket.
We do what we can......
rScotty

 

[Vigo327]

On my [AFFILIATE=1, nofollow=true, newwindow=true, title="Kubota"]Kubota[/AFFILIATE] B8200 with BF300 loader, one thing i really like about it is the huge crossmember between the loader arms out near the bucket. I see most loaders seem to have a round tubular section aka pipe there, and while that makes sense for a torsion-resisting member, i suspect the sheer size of the rectangular beam on mine (around 4x6”) is probably stronger in torsion than a lot of the round sections i see, especially on ‘same size’ loaders. It’s only rated to lift ~700lbs to full height (300kg, thus the BF300). The bucket’s 1/2” cutting edge is pretty well bowed, but the loader arms themselves are perfect.

I know that crossmember is not the only factor but seeing that honking chunk of metal go up and down in front of me does make me feel betterabout being rough with the loader, and so far so good.

I dont consider this a particularly dangerous thing to subject a loader to (maybe the load!) but i have ‘cheated’ extra lift out of the loader repeatedly by rocking back and forth in place while lifting or by dumping bucket slightly while lifting and then curling back up. Ive definitely lifted things it wasn’t intended to lift and other than the bowed bucket which was like that when i got it and i have not managed to make it any worse, the rest of this loader is 100% ok.