Possible hydraulic issue on tractor?

J_J

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On your Kubota, is your regen not in the first part of lever ?

Regen dump pressure should be lower than full dump.

Power dump at end of extension should be full pressure.

Is this sound a hyd clunk or a mechanical clunk. Is the bucket slamming on the mounting pins.

Rear remotes with nothing attached would be the same as a deadhead.

Any pressure you see is the result of a restriction or a cyl at full extension or retraction.

Do you think the pressure reading was from the hyd blk relief valve or the loader relief valve?
 
  
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namesray

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1. On your Kubota, is your regen not in the first part of lever ?

2. Regen dump pressure should be lower than full dump.

3. Power dump at end of extension should be full pressure.

4. Is this sound a hyd clunk or a mechanical clunk. Is the bucket slamming on the mounting pins.

5. Rear remotes with nothing attached would be the same as a deadhead.

6. Any pressure you see is the result of a restriction or a cyl at full extension or retraction.

7. Do you think the pressure reading was from the hyd blk relief valve or the loader relief valve?

Ok will answer each one in a list.

1. I may be confused on regen dump and full dump terms. When I moved the lever to 1st stage dump, the pressure read 100 psi real quick then went right to 0 psi. When I moved lever all the way to right (2nd stage) then the pressure read 2200psi and engine labored a slight bit.

2. If regen dump is first stage of valve lever dump, then yes, regen dump pressure was 100psi then quickly went to 0 psi during dump. Full dump pressure was higher at 2200 psi.

3. Power dump or full dump pressure read 2200psi during bucket stroke. Once cylinder stroke reached end, pressure went up to 2300 psi.

4. This clunk sound I am talking about is a hydraulic clunk. It is NOT the bucket bouncing or linkage hitting. The sound seems to be comming out of the in, pb, and tank lines from the tractor hyp ports and the loader valve. Sounds like a quick "click" or "clunk" sound. It is very distinct. Not a faint little sound. It is louder the quicker I move the lever back to neutral. Kinda like a quick snap or clunk sound.

5. Rear remotes had nothing attached and when I moved remote valve lever it sounded like it was deadheading and pressure went to 2300psi.

6. Unsure what you mean about "ANY pressure I see is the result of a restriction or cylindr at full extension or retraction." When I "lifted" the loader boom guage read 700psi. When the boom went all the way up to the end and I held lever there, the pressure went up to 2300 psi. When I lowered boom, pressure stayed at 0 psi. Same with all function lowerings, pressure stayed at 0 psi, boom down, bucket dump (1st stage), and 3pt down. When each was lifted, pressure was around 700 psi. ARE YOU SAYING THE PRESSURES SHOULD BE 0 PSI DURING ALL LIFT FUNCTIONS? When each function reached the end of its cylinder stroke the pressure went up to 2300 psi until I let off lever.

7. I have no idea what you mean by "do I think the pressure reading was from the hyd block relief valve or loader relief valve."
I am sorry I am uneducated on this. What pressure reading do you mean? Any pressure or the max pressure number 2300 psi??? I know where the pressure relief is on the loader valve, but have no idea where it is on the tractor or how to tell which one is working when.
 

J_J

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About any pressure.

Whenever you activate any hyd component, The flow is pushing on a cyl piston and that piston is pushing on a load. The amount of the load will determine the pressure. Just raising an empty bucket does not require much pressure. Scoop up a load of dirt and you may exceed the relief pressure.

It could be just the weight of the bucket or maybe 500 lbs of dirt. The cyl is going to develop the pressure because of the weight or restriction. If you restrict the flow, the pressure will rise.

Whenever you retract a cyl, the cyl out flow is used fluid and it is going to tank with very little restriction.. The pump flow is still passing through all valves to tank.

It is hard to relate to a hyd clunk as when you bring the lever back to neutral, you are simply reducing the flow to the cyl in use. The hyd flow will now shift from cyl to PB, and pass downstream.

About the relief.

Before the tractor had a loader, it still had the hyd blk with a relief valve for the tractor hyd.

With no loader attached, the flow went to the hyd blk with relief and then to the 3pt. That relief was your hyd protection before a loader was added.

Now with a loader, the flow is from the hyd blk to the loader which also has a relief. The loader PB may go back to the hyd blk or go to the remote valve.

Whichever relief is set lower is doing all the relieving. They should be set the same.

Either relief can cause problems.

You now also have remotes, and it has a relief valve. Recommend you set them all the same as the tractor relief which is on the hyd blk.
 
  
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namesray

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Ok. I am following this. I know the relief valve on the loader is on the loader valve next to the in port.

The hyd blk? Is that the ports under the tractor, on right side that the loader in, pb, and tank lines come out of to go to/from loadr valve? If so, where is the relief here and what does it look like? Would it look simular to the one on the loader valve? I guess I don't touch this one anyway.

Now where is the relief for the rear remotes located? Would that look simular to the relief on the loader valve? I have tried to find if the remotes had one before, but ddidn't see it.

Next question, how would I set all 3 equal?
 
  
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namesray

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I ran out and checked for the hyd block relief and the rear remote releif. The only thing I could see are larger bolt head (7/8" to 1") at bottom of hyd block, one seemingly for tank line and other for power beyond line.???

And another large bolt head (looks over 1" socket size) at bottom of rear remote valve.

Just looks like all 3 bolt heads just thread in or out with no locking nut or such. Am I on the right track here? The relief on the loader valve looks like a set screw with locking nut. I can't find anything like this at hyd block or rear remotes. ????
 

J_J

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Find out the tractor relief on the hyd blk and set the other reliefs to that setting.

I believe the tractor relief on the hyd blk is set by shims.

The other valves may be by adjusting screw.

Most relief valves are close to the IN port.

Show me a picture of the loader valve and the remote valve and I should be able to point out the relief valve.

On the adjusting screw type relief, you watch the hyd gauge and if the pressure changes, that is the relief you are adjusting.

You can positively identify the relief that is activated by looking at the tank port with hose removed.

When you fully retract a cyl, a relief will activate and route pump flow to tank.
 

Leejohn

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Here is the psi you posted curl bucket 1500 "clunk", Dump bucket 200 "clunk"
It should not take 1500 psi to curl a empty bucket. If (and not saying you did) use the bucket as a doser blade you could have bent rods. Also just maybe you might have a loose piston that is slamming into the rod, that would give you a clunking sound.
If it was me I would unhook the bucket cyls from the bucket then check there psi. of the curl. I would also when the cyl is about half way in move it in and out to see if you can rock the picton and get a clunk. The clunk well not be as loud without any load on it. It well have to be done on both cyl because one cyl well move faster then the other. I would do it on the slow cyl first, that would be most likely the one.

BTY your tractor relief is the the bolt that hangs down the lowest on the hyd block.
 

J_J

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If he had a loose piston, he would never build up relief pressure.
 
  
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namesray

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We messed with the relief screw on the loader valve before. Turned it up full turn, then back to orginal place, then turned it down, and put back to orginal setting. There was no difference in clunk at any setting we put it at.

How many full turns might it take to get a noticable pressure difference? Maybe we didn't turn it far enough?

The "bolt" head I thought was the relief on the rear remote was not it. It was the lever valve spring action thingy, whatever it is technically called.

I was told the rear remote is a closed loop system tied in with the 3pt and the relief is located next to the knob that controls 3ph lowering speed. I found that.

So I guess there is only 2 relief valves on my tractor???

Tonight I learned another new thing about my clunk noise in the loader hydraulics. It will also make that clunk noise when I put loader boom in the float detent position. Rather boom is in the air or resting on the ground, putting it in float will make that same clunk sound as when I return the bucket function to neutral.

It won't make clunk noise when just raising or lowering the boom, only putting it into float.

I am very confused here on if this is normal or not. I know there will be a click noise when the lever goes into float detent, but this is a different noise.

Maybe I should try to post a video of this noise and the tractor. I think that would be a big help. How do you get a video on here on tbn? I already have a video on this tablet, but I don't know how to put it here on tbn.
 

J_J

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Your tractor is open center.

The thing you found by the descent knob is not the relief valve for the 3pt, that is the safety valve.

Your tractor relief valve is where I said it was.

In order to adjust a relief valve, you have to work the hyd to get max pressure.

You 3pt relief is at the bottom of the hyd blk.

Your relief valve setting is 2631 psi

Perhaps I should quit giving advise.

We don't get pictures when we ask for them.

People do not follow advice.

I look hard to find this data.
 
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