Possible hydraulic issue on tractor?

  
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namesray

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I have not been able to get a guage on it yet. A new valve is being shipped and should be here in a couple of days. Dealer said sound like it has to be in valve and they covering it under warrenty, but other then that they "never heard of anything like this before."

Seems like my issue would be a common problem that would have common causes.

As I am waiting for this valve to show up, I have been trying to learn a little along the way and have been trying to dig up some info on hydraulic noises.

I have read about "hydraulic hammering" which I kinda think is what I have going on. Says hydraulic hammering caused by fluid moving through system and being suddenly slowed or stopped, thus causing a surge and clunk noise as pressure slamms into its restriction or sudden valve change.

This can be fixed with flow restrictors and such, which I don't think is what I have to do.

I think in my loader valve there is something wrong, broke, cracked, stuck, bad o ring, whichever, in the bucket function neautral valving causing all my issues. Such as a blockage that
1. Is causing flow restriction and my noise I am hearing when returning valve to neautral (fluid slamming into this blockage instead of moving freely through its open center circut) 2. Causing flow restriction and fluid/hoses to heat up.
3. Causing flow restriction and the noise I hear in the pump, like a electrial shock, this being cavitation.
4. Causing air to get into the bucket cylinders, thus not allowing the bucket to hold itself in dump position when backdragging. Bucket will dump, but as soon as I start to back up to drag, bucket cylinders would collapse or give unless I help valve in dump function for while back dragging. I think cylinders would collapse with the air in them (fluid wouldn't dump bucket, gravity did due to limited hyd fluid flow caused by blockage)

I hope you guys are understanding wat I am trying to say. I am not good at explaining things either. Any way this is my theory. What do you guys think? I hope this new valve fixes my issues.
 
  
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namesray

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Today got new valve on. Did not fix issues. So I guess it's not in the loader valve.

Have some new info I tried out tonight.

Switched hoses for loader boom up/down with bucket curl/dump. Noise was still in the same valve function, so it is not the loader cylinders or hoses.

We switched the "in" and "tank" lines and nothing worked.

Switched "tank" line with "power beyond" line and eureka! Noise in loader valve was gone and the loader worked!!! However, when I checked the 3 point hitch lift, that did not work. If I ran a loader function same time as lifting 3ph then 3ph would work. So no return pressure??? I don't know.

We put all lines back to orginal. Everything worked again, but back to the clunk noise in lines when returning loader bucket valve function to neautral.

I went bush hogging and when tractor fully warmed up I checked how hot the lines were to and from loader valve. The "in" line was hot. The "tank" line was only warm. The "power beyond" line was hot. Is this normal?
 

J_J

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I don't believe you have told us all that we need to know to help diagnose the problem.

You apparently do not have a correct flow path.

You said you have no 3pt.

Where is the PB flow from the loader valve going.

Where are the tank lines connected.

Are your hoses connected to the hyd block?

Do you have a remote valve, and how is it connected?

Is your loader valve fed from the hyd blk?
 

Leejohn

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Do you have the power beyond fitting or plug in the new valve?
 

J_J

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If he had the hoses correct, the 3pt would work.

If you were bush hogging, how did you operate the 3pt?
 
  
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namesray

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I don't believe you have told us all that we need to know to help diagnose the problem.

You apparently do not have a correct flow path.

You said you have no 3pt.

Where is the PB flow from the loader valve going.

Where are the tank lines connected.

Are your hoses connected to the hyd block?

Do you have a remote valve, and how is it connected?

Is your loader valve fed from the hyd blk?

Im going to list answers in the same order as above statements/questions.

1. I dont know about correct flow path.

2. The 3pt hitch works normal. It didn't work at all during the time we switched the "power beyond" line with the "tank" line (lines "c" and "d" in my previous pictures). We stitched pb and tank lines at the loader valve. Loader worked, all 4 functions and made no clunk noise. BUT when pb and tank lines were switched, the 3pt would not lift, UNLESS I worked both a loader function and the 3pt lift at the same time. So we put pb and tank lines back to there orginal locations. 3pt worked again, but back to clunk noise when returning bucket function back to neutral. All lines are back to where they orginally were with my orginal problem still occurring.

3. The pb flow from the loader is going back to the main ports in the tractor and appears to be correct location according to diagrams in manuals.

4. The tank line that I know of comes out of loader valve and goes back to tank port on main tractor port. Tank line is on same side of loader valve as the pb line. Both go from loader valve down to main tractor port.

5. Yes all 3 hoses to/from loader valve run straight out of tractor main hyd ports to loader valve. Lines "b" "c" "d" in my previous pictures. Line b is "in". Line "c" is power beyond, and line "d" is tank.

6. Yes I have 1 remote valve in rear. The only lines I see to this come out of the rear case and directly to rear valve. Rear valve is a 2 way, with open center neutral. One line comes directly out of tractor rear case. The other 2 lines seem to come out of a small block on rear case. And from the remote valve there is the 2 lines that run to the plug ports for an implement hoses. I have not had an implement hooked up to rear remotes yet.

7. Yes, loader valve is fed out of hyd block, next to hyd filter, like I mentioned in #5.

Take note here, I am no mechanic or hyd person. I believe I have labled the lines as they are.
 

J_J

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Where do you keep the 3pt lever?

Should be in neutral except when in use.

If the lever is up, it will cause back pressure and maybe the sounds you are experiencing.
 

J_J

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Where do you keep the 3pt lever?

Should be in neutral except when in use.

If the lever is up, it will cause back pressure and maybe the sounds you are experiencing.
 
  
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namesray

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The 3pt system is position control. The lever position determines 3ph height and when placed at whatever position 1 through 9, should shut off after 3ph reaches desired height. Even if lever is all the way to top, it should stop system when 3ph reaches all the way up.

I have noticed at times I can still hear a little squeal noise in system and if I bump 3ph lever down little bit the noise stops. I can't tell if this is causing the problem, or a RESULT of SOMETHING ELSE causing a pressure problem.

I worked tractor all day yesterday and the hyd pump was making that static like noise, like flicking a plastic bag or rubbing a plastic candy wrapper in your fingers. The noise comes and goes, but only starts once system is fully warm.

This pump noise is what concerns me the most. I also thought about back pressure building. I moved every lever thinking I could release pressure and hyd pump noise would stop, but it didn't. The static noise is not always there, sometimes its quiet for a couple minutes, and sometimes it keeps going.

I can feel a pulse in a hyd line comming out of the hyd pump on side of engine with this static noise. I will try to get a picture of pump with that line. That pulse I feel is the static noise. Is this noise cavitation or could it just be normal?
 
  
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namesray

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Here is a picture of the hyd pump. Its the line off the shiny bolt on the left. For some reason picture is ratated once I post them here, so every picture is sideways. This line runs to the steering box under the consol. Could I have a power steering issue causing all these other problems?
 

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