Kioti 4510 AL41

[Aussiekioti]

First time poster, hoping for someone who has had similar problem or can shed some light on the AL41 Loader components. Only 150 hrs on my 2012 Kioti, don't know if oils or filter have ever been changed but will do soon. When using forks and lifting a heavy pallet (Approx 350kgs) the arms lift it ok, but the forks then "sag/droop" so anything on the pallet would slide off. Yes it is heavy and worse when further forward/out on the forks, but everyone I speak to says it should not droop. It should hold the pressure. I had a hydraulics guy look at it and he measured the pressures and the curl pressure was as low as 1500psi maybe 1800psi under load. He bypassed the valve on the arms (self leveling valve I'm told, but he was not familiar with it so did not know what was normal operation of the valve). When bypassed, it did not droop and the full pressure was getting to the curl rams. Operation was a little jerky/responsive and I think we lost the levelling feature. To him this meant the problem was in the valve, not oil filter and oil age etc. But he could not do anything further as Kioti dealer would not give him, or did not know the internal workings of the valve or a technical schematic etc. I have also turned down the relieve valve on this self leveling valve by a quarter of a turn and this seems to have improved it, but I don't want to go too far and this was after the hydraulics guy was gone so I did not have a pressure gauge when doing it. The Kioti dealer has the complete valve block setup in stock for $500, but this would not necessarily fix the problem. I contacted Walvoil directly and they said failure very unusual, likely just the relief valve in it, so they sold me one of these for $50 which I have not yet installed. My questions are: (1) Anyone else have similar experience
(2) Do all AL41s have this self leveling valve or is it an option (ie: can I just bypass it completely without issue if wanted.
(3) Is the relief valve in this leveling valve the whole system relief valve or just some sort of adjustment for the levelling function? How much can I screw it in without worry? If not all AL41 have a self leveling valve, what do they then have as a relief valve?
(4) does anyone know what psi values should be at both the rams, if I know this I may be able to measure and adjust to the correct settings?
(5) Does anyone know how many psi the rams can take until seal failure? (To help determine relief valve setting, as fully screwed in this valve has a top range of I think something like 2800psi.
(6) Is there any other relief valves in this circuit and if so where?
I will attempt to post a photo of the valve block I mention which is for self levelling, in which the black thing on top is a relief valve

 

[Leejohn]

The thing you are calling a relief valve might not be. I would guess that is flow adjustment to set the self leveling. The relief valve should be in the loader control valve.

 

[Aussiekioti]

Thanks Leejohn, can you see the photo in my question? So the adjustment on this valve would do what...can I safely screw in the relief valve thing and or how do you adjust and why when this is bypassed my problem disappears? The loader control valve, is this the big stick control, I think called DCV also. ?

 

[ptsg]

So, you have a mechanical self leveling loader.

All mechanical self leveling loaders will have that relief valve. The relief valve is there to prevent damage to linkages, pins, etc.

Here is an example, let's say you fully dumped your bucket near the ground ( full dump, no stroke left on the cylinder). If you lift the loader, the mechanical linkage, will try to dump the bucket further, but that ain't happening because it's already hitting the stops. So there is where the relief valve comes into play. Basically opens, allowing the cylinder to give, before stuff breaks.

Same principle happens in full height and full curl. Once you come down, something needs to give, that will be the relief valve.

Now, someone has been messing with the valve before. That's why you may have been having problems. It's my understanding that this valve should be set at system pressure, or slightly below.

350kg is nothing for that tractor. These tractors usually run at 2500 to 2600 psi or around 180bar on system pressure. That relief valve should be set somewhere around that. Not higher, otherwise the lift cylinders won't be able to over come the relief valve.

A service manual for the loader and tractor would be ideal to set this thing right. Since you got 2800 psi with the relief valve cranked all the way down, I would set it somewhere around 2400 to 2500 psi and work the tractor for a while.

Oh, and welcome to TBN.

 

[oldnslo]

Pure Mechanical self leveling does not require any relief valve or any hydraulic input it is all done with mechanical linkage.

Hydraulic self leveling which is what you are describing should not reduce curl pressure if operating correctly. Without a schematic can only guess on what valves are in that block. Some models have option to turn leveling feature off others do not. Like Ptsg states there is some form of safety to allow self level to work if curl cylinders are at end of stroke but again this should not limit curl pressure below system operating pressure.

If you just try and curl with a load does that work properly or is it always weak?

 

[Aussiekioti]

Is my photo in my post visible? I'm now confused with what is mechanical and what is hydraulic. I think I have hydraulic self leveling and the block shown in my photo is I think the device. It doesn't seem to have any way of turning off the feature. The curl seems to work fine and mostly does not seem weak, but the tractor is new to us. I can fill a bucket of soil and it curls without problem and does not seem slow. The only problem I have with the curl is that when under a heavy pallet, it won't curl and or will just curl but slowly "flop/droop" back down. If the black valve in the photo can be adjusted and result in higher curl pressure it sounds like it is ok to do this? Knowing there should be no loss of pressure due to the self leveling feature is good to know. I think I will be changing the oil and filter and the black valve/spring assembly and will report back, but will first just wind down the valve and try to determine which fix actually has the biggest impact. Time to buy a pressure gauge setup! Still keen for any other tips or experiences with the block in the photo and confirmation that adjusting this valve will/can increase curl pressure. I've also read about some tractors have a "Regen" function for dumping, how do I know if I have that?
Thanks for the comments so far!!

 

[ptsg]

You have a mechanical self leveling loader. Note the parallel arms/linkage over the main loader arms. But this system needs a safety relief valve (the block shown on the picture). If that relief valve is set low (as it is now), the bucket will drop under load or weight of the 350kg pallet in this case.

That relief valve should be set around the system pressure. Somewhere around 2500 to 2600 PSI.

 

[Aussiekioti]

Ahhhh, now it is all making much more sense, this block really is only a relief valve!! Knowing that I think I will buy a gauge, change oil and filter, change the relief valve bits then adjust. OMG thanks for the help!!! Will report back here when done.

 

[oldnslo]

Aussie,
Could you please take a photo showing the complete side view of your loader. Reason for asking is that I am curious to see if you the mechanical version of self level in Europe is different than what I have seen in the USA. Here in the USA I have never seen a mechanical system with a manifold like that in your picture.

 

[Aussiekioti]

Hi, see attached photos, hopefully!! While I have your attention, I also have a loader joystick which today only learnt it had float mode, which I alsoearnt can be handy. But this stick also has two buttons, one does the open/close of the 4in1 bucket. What does the other do or is it for other uses possibly not on my tractor? Lastly in my reading, when dumping a load I've read that some loaders have a REGEN function. How do I know if I'd have this and is it important?